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+import platform
+import warnings
+import fnmatch
+import itertools
+import pytest
+import sys
+import os
+import operator
+from fractions import Fraction
+from functools import reduce
+from collections import namedtuple
+
+import numpy.core.umath as ncu
+from numpy.core import _umath_tests as ncu_tests
+import numpy as np
+from numpy.testing import (
+    assert_, assert_equal, assert_raises, assert_raises_regex,
+    assert_array_equal, assert_almost_equal, assert_array_almost_equal,
+    assert_array_max_ulp, assert_allclose, assert_no_warnings, suppress_warnings,
+    _gen_alignment_data, assert_array_almost_equal_nulp, IS_WASM, IS_MUSL,
+    IS_PYPY
+    )
+from numpy.testing._private.utils import _glibc_older_than
+
+UFUNCS = [obj for obj in np.core.umath.__dict__.values()
+         if isinstance(obj, np.ufunc)]
+
+UFUNCS_UNARY = [
+    uf for uf in UFUNCS if uf.nin == 1
+]
+UFUNCS_UNARY_FP = [
+    uf for uf in UFUNCS_UNARY if 'f->f' in uf.types
+]
+
+UFUNCS_BINARY = [
+    uf for uf in UFUNCS if uf.nin == 2
+]
+UFUNCS_BINARY_ACC = [
+    uf for uf in UFUNCS_BINARY if hasattr(uf, "accumulate") and uf.nout == 1
+]
+
+def interesting_binop_operands(val1, val2, dtype):
+    """
+    Helper to create "interesting" operands to cover common code paths:
+    * scalar inputs
+    * only first "values" is an array (e.g. scalar division fast-paths)
+    * Longer array (SIMD) placing the value of interest at different positions
+    * Oddly strided arrays which may not be SIMD compatible
+
+    It does not attempt to cover unaligned access or mixed dtypes.
+    These are normally handled by the casting/buffering machinery.
+
+    This is not a fixture (currently), since I believe a fixture normally
+    only yields once?
+    """
+    fill_value = 1  # could be a parameter, but maybe not an optional one?
+
+    arr1 = np.full(10003, dtype=dtype, fill_value=fill_value)
+    arr2 = np.full(10003, dtype=dtype, fill_value=fill_value)
+
+    arr1[0] = val1
+    arr2[0] = val2
+
+    extractor = lambda res: res
+    yield arr1[0], arr2[0], extractor, "scalars"
+
+    extractor = lambda res: res
+    yield arr1[0, ...], arr2[0, ...], extractor, "scalar-arrays"
+
+    # reset array values to fill_value:
+    arr1[0] = fill_value
+    arr2[0] = fill_value
+
+    for pos in [0, 1, 2, 3, 4, 5, -1, -2, -3, -4]:
+        arr1[pos] = val1
+        arr2[pos] = val2
+
+        extractor = lambda res: res[pos]
+        yield arr1, arr2, extractor, f"off-{pos}"
+        yield arr1, arr2[pos], extractor, f"off-{pos}-with-scalar"
+
+        arr1[pos] = fill_value
+        arr2[pos] = fill_value
+
+    for stride in [-1, 113]:
+        op1 = arr1[::stride]
+        op2 = arr2[::stride]
+        op1[10] = val1
+        op2[10] = val2
+
+        extractor = lambda res: res[10]
+        yield op1, op2, extractor, f"stride-{stride}"
+
+        op1[10] = fill_value
+        op2[10] = fill_value
+
+
+def on_powerpc():
+    """ True if we are running on a Power PC platform."""
+    return platform.processor() == 'powerpc' or \
+           platform.machine().startswith('ppc')
+
+
+def bad_arcsinh():
+    """The blocklisted trig functions are not accurate on aarch64/PPC for
+    complex256. Rather than dig through the actual problem skip the
+    test. This should be fixed when we can move past glibc2.17
+    which is the version in manylinux2014
+    """
+    if platform.machine() == 'aarch64':
+        x = 1.78e-10
+    elif on_powerpc():
+        x = 2.16e-10
+    else:
+        return False
+    v1 = np.arcsinh(np.float128(x))
+    v2 = np.arcsinh(np.complex256(x)).real
+    # The eps for float128 is 1-e33, so this is way bigger
+    return abs((v1 / v2) - 1.0) > 1e-23
+
+
+class _FilterInvalids:
+    def setup_method(self):
+        self.olderr = np.seterr(invalid='ignore')
+
+    def teardown_method(self):
+        np.seterr(**self.olderr)
+
+
+class TestConstants:
+    def test_pi(self):
+        assert_allclose(ncu.pi, 3.141592653589793, 1e-15)
+
+    def test_e(self):
+        assert_allclose(ncu.e, 2.718281828459045, 1e-15)
+
+    def test_euler_gamma(self):
+        assert_allclose(ncu.euler_gamma, 0.5772156649015329, 1e-15)
+
+
+class TestOut:
+    def test_out_subok(self):
+        for subok in (True, False):
+            a = np.array(0.5)
+            o = np.empty(())
+
+            r = np.add(a, 2, o, subok=subok)
+            assert_(r is o)
+            r = np.add(a, 2, out=o, subok=subok)
+            assert_(r is o)
+            r = np.add(a, 2, out=(o,), subok=subok)
+            assert_(r is o)
+
+            d = np.array(5.7)
+            o1 = np.empty(())
+            o2 = np.empty((), dtype=np.int32)
+
+            r1, r2 = np.frexp(d, o1, None, subok=subok)
+            assert_(r1 is o1)
+            r1, r2 = np.frexp(d, None, o2, subok=subok)
+            assert_(r2 is o2)
+            r1, r2 = np.frexp(d, o1, o2, subok=subok)
+            assert_(r1 is o1)
+            assert_(r2 is o2)
+
+            r1, r2 = np.frexp(d, out=(o1, None), subok=subok)
+            assert_(r1 is o1)
+            r1, r2 = np.frexp(d, out=(None, o2), subok=subok)
+            assert_(r2 is o2)
+            r1, r2 = np.frexp(d, out=(o1, o2), subok=subok)
+            assert_(r1 is o1)
+            assert_(r2 is o2)
+
+            with assert_raises(TypeError):
+                # Out argument must be tuple, since there are multiple outputs.
+                r1, r2 = np.frexp(d, out=o1, subok=subok)
+
+            assert_raises(TypeError, np.add, a, 2, o, o, subok=subok)
+            assert_raises(TypeError, np.add, a, 2, o, out=o, subok=subok)
+            assert_raises(TypeError, np.add, a, 2, None, out=o, subok=subok)
+            assert_raises(ValueError, np.add, a, 2, out=(o, o), subok=subok)
+            assert_raises(ValueError, np.add, a, 2, out=(), subok=subok)
+            assert_raises(TypeError, np.add, a, 2, [], subok=subok)
+            assert_raises(TypeError, np.add, a, 2, out=[], subok=subok)
+            assert_raises(TypeError, np.add, a, 2, out=([],), subok=subok)
+            o.flags.writeable = False
+            assert_raises(ValueError, np.add, a, 2, o, subok=subok)
+            assert_raises(ValueError, np.add, a, 2, out=o, subok=subok)
+            assert_raises(ValueError, np.add, a, 2, out=(o,), subok=subok)
+
+    def test_out_wrap_subok(self):
+        class ArrayWrap(np.ndarray):
+            __array_priority__ = 10
+
+            def __new__(cls, arr):
+                return np.asarray(arr).view(cls).copy()
+
+            def __array_wrap__(self, arr, context):
+                return arr.view(type(self))
+
+        for subok in (True, False):
+            a = ArrayWrap([0.5])
+
+            r = np.add(a, 2, subok=subok)
+            if subok:
+                assert_(isinstance(r, ArrayWrap))
+            else:
+                assert_(type(r) == np.ndarray)
+
+            r = np.add(a, 2, None, subok=subok)
+            if subok:
+                assert_(isinstance(r, ArrayWrap))
+            else:
+                assert_(type(r) == np.ndarray)
+
+            r = np.add(a, 2, out=None, subok=subok)
+            if subok:
+                assert_(isinstance(r, ArrayWrap))
+            else:
+                assert_(type(r) == np.ndarray)
+
+            r = np.add(a, 2, out=(None,), subok=subok)
+            if subok:
+                assert_(isinstance(r, ArrayWrap))
+            else:
+                assert_(type(r) == np.ndarray)
+
+            d = ArrayWrap([5.7])
+            o1 = np.empty((1,))
+            o2 = np.empty((1,), dtype=np.int32)
+
+            r1, r2 = np.frexp(d, o1, subok=subok)
+            if subok:
+                assert_(isinstance(r2, ArrayWrap))
+            else:
+                assert_(type(r2) == np.ndarray)
+
+            r1, r2 = np.frexp(d, o1, None, subok=subok)
+            if subok:
+                assert_(isinstance(r2, ArrayWrap))
+            else:
+                assert_(type(r2) == np.ndarray)
+
+            r1, r2 = np.frexp(d, None, o2, subok=subok)
+            if subok:
+                assert_(isinstance(r1, ArrayWrap))
+            else:
+                assert_(type(r1) == np.ndarray)
+
+            r1, r2 = np.frexp(d, out=(o1, None), subok=subok)
+            if subok:
+                assert_(isinstance(r2, ArrayWrap))
+            else:
+                assert_(type(r2) == np.ndarray)
+
+            r1, r2 = np.frexp(d, out=(None, o2), subok=subok)
+            if subok:
+                assert_(isinstance(r1, ArrayWrap))
+            else:
+                assert_(type(r1) == np.ndarray)
+
+            with assert_raises(TypeError):
+                # Out argument must be tuple, since there are multiple outputs.
+                r1, r2 = np.frexp(d, out=o1, subok=subok)
+
+
+class TestComparisons:
+    import operator
+
+    @pytest.mark.parametrize('dtype', np.sctypes['uint'] + np.sctypes['int'] +
+                             np.sctypes['float'] + [np.bool_])
+    @pytest.mark.parametrize('py_comp,np_comp', [
+        (operator.lt, np.less),
+        (operator.le, np.less_equal),
+        (operator.gt, np.greater),
+        (operator.ge, np.greater_equal),
+        (operator.eq, np.equal),
+        (operator.ne, np.not_equal)
+    ])
+    def test_comparison_functions(self, dtype, py_comp, np_comp):
+        # Initialize input arrays
+        if dtype == np.bool_:
+            a = np.random.choice(a=[False, True], size=1000)
+            b = np.random.choice(a=[False, True], size=1000)
+            scalar = True
+        else:
+            a = np.random.randint(low=1, high=10, size=1000).astype(dtype)
+            b = np.random.randint(low=1, high=10, size=1000).astype(dtype)
+            scalar = 5
+        np_scalar = np.dtype(dtype).type(scalar)
+        a_lst = a.tolist()
+        b_lst = b.tolist()
+
+        # (Binary) Comparison (x1=array, x2=array)
+        comp_b = np_comp(a, b).view(np.uint8)
+        comp_b_list = [int(py_comp(x, y)) for x, y in zip(a_lst, b_lst)]
+
+        # (Scalar1) Comparison (x1=scalar, x2=array)
+        comp_s1 = np_comp(np_scalar, b).view(np.uint8)
+        comp_s1_list = [int(py_comp(scalar, x)) for x in b_lst]
+
+        # (Scalar2) Comparison (x1=array, x2=scalar)
+        comp_s2 = np_comp(a, np_scalar).view(np.uint8)
+        comp_s2_list = [int(py_comp(x, scalar)) for x in a_lst]
+
+        # Sequence: Binary, Scalar1 and Scalar2
+        assert_(comp_b.tolist() == comp_b_list,
+            f"Failed comparison ({py_comp.__name__})")
+        assert_(comp_s1.tolist() == comp_s1_list,
+            f"Failed comparison ({py_comp.__name__})")
+        assert_(comp_s2.tolist() == comp_s2_list,
+            f"Failed comparison ({py_comp.__name__})")
+
+    def test_ignore_object_identity_in_equal(self):
+        # Check comparing identical objects whose comparison
+        # is not a simple boolean, e.g., arrays that are compared elementwise.
+        a = np.array([np.array([1, 2, 3]), None], dtype=object)
+        assert_raises(ValueError, np.equal, a, a)
+
+        # Check error raised when comparing identical non-comparable objects.
+        class FunkyType:
+            def __eq__(self, other):
+                raise TypeError("I won't compare")
+
+        a = np.array([FunkyType()])
+        assert_raises(TypeError, np.equal, a, a)
+
+        # Check identity doesn't override comparison mismatch.
+        a = np.array([np.nan], dtype=object)
+        assert_equal(np.equal(a, a), [False])
+
+    def test_ignore_object_identity_in_not_equal(self):
+        # Check comparing identical objects whose comparison
+        # is not a simple boolean, e.g., arrays that are compared elementwise.
+        a = np.array([np.array([1, 2, 3]), None], dtype=object)
+        assert_raises(ValueError, np.not_equal, a, a)
+
+        # Check error raised when comparing identical non-comparable objects.
+        class FunkyType:
+            def __ne__(self, other):
+                raise TypeError("I won't compare")
+
+        a = np.array([FunkyType()])
+        assert_raises(TypeError, np.not_equal, a, a)
+
+        # Check identity doesn't override comparison mismatch.
+        a = np.array([np.nan], dtype=object)
+        assert_equal(np.not_equal(a, a), [True])
+
+    def test_error_in_equal_reduce(self):
+        # gh-20929
+        # make sure np.equal.reduce raises a TypeError if an array is passed
+        # without specifying the dtype
+        a = np.array([0, 0])
+        assert_equal(np.equal.reduce(a, dtype=bool), True)
+        assert_raises(TypeError, np.equal.reduce, a)
+
+    def test_object_dtype(self):
+        assert np.equal(1, [1], dtype=object).dtype == object
+        assert np.equal(1, [1], signature=(None, None, "O")).dtype == object
+
+    def test_object_nonbool_dtype_error(self):
+        # bool output dtype is fine of course:
+        assert np.equal(1, [1], dtype=bool).dtype == bool
+
+        # but the following are examples do not have a loop:
+        with pytest.raises(TypeError, match="No loop matching"):
+            np.equal(1, 1, dtype=np.int64)
+
+        with pytest.raises(TypeError, match="No loop matching"):
+            np.equal(1, 1, sig=(None, None, "l"))
+
+    @pytest.mark.parametrize("dtypes", ["qQ", "Qq"])
+    @pytest.mark.parametrize('py_comp, np_comp', [
+        (operator.lt, np.less),
+        (operator.le, np.less_equal),
+        (operator.gt, np.greater),
+        (operator.ge, np.greater_equal),
+        (operator.eq, np.equal),
+        (operator.ne, np.not_equal)
+    ])
+    @pytest.mark.parametrize("vals", [(2**60, 2**60+1), (2**60+1, 2**60)])
+    def test_large_integer_direct_comparison(
+            self, dtypes, py_comp, np_comp, vals):
+        # Note that float(2**60) + 1 == float(2**60).
+        a1 = np.array([2**60], dtype=dtypes[0])
+        a2 = np.array([2**60 + 1], dtype=dtypes[1])
+        expected = py_comp(2**60, 2**60+1)
+
+        assert py_comp(a1, a2) == expected
+        assert np_comp(a1, a2) == expected
+        # Also check the scalars:
+        s1 = a1[0]
+        s2 = a2[0]
+        assert isinstance(s1, np.integer)
+        assert isinstance(s2, np.integer)
+        # The Python operator here is mainly interesting:
+        assert py_comp(s1, s2) == expected
+        assert np_comp(s1, s2) == expected
+
+    @pytest.mark.parametrize("dtype", np.typecodes['UnsignedInteger'])
+    @pytest.mark.parametrize('py_comp_func, np_comp_func', [
+        (operator.lt, np.less),
+        (operator.le, np.less_equal),
+        (operator.gt, np.greater),
+        (operator.ge, np.greater_equal),
+        (operator.eq, np.equal),
+        (operator.ne, np.not_equal)
+    ])
+    @pytest.mark.parametrize("flip", [True, False])
+    def test_unsigned_signed_direct_comparison(
+            self, dtype, py_comp_func, np_comp_func, flip):
+        if flip:
+            py_comp = lambda x, y: py_comp_func(y, x)
+            np_comp = lambda x, y: np_comp_func(y, x)
+        else:
+            py_comp = py_comp_func
+            np_comp = np_comp_func
+
+        arr = np.array([np.iinfo(dtype).max], dtype=dtype)
+        expected = py_comp(int(arr[0]), -1)
+
+        assert py_comp(arr, -1) == expected
+        assert np_comp(arr, -1) == expected
+        scalar = arr[0]
+        assert isinstance(scalar, np.integer)
+        # The Python operator here is mainly interesting:
+        assert py_comp(scalar, -1) == expected
+        assert np_comp(scalar, -1) == expected
+
+
+class TestAdd:
+    def test_reduce_alignment(self):
+        # gh-9876
+        # make sure arrays with weird strides work with the optimizations in
+        # pairwise_sum_@TYPE@. On x86, the 'b' field will count as aligned at a
+        # 4 byte offset, even though its itemsize is 8.
+        a = np.zeros(2, dtype=[('a', np.int32), ('b', np.float64)])
+        a['a'] = -1
+        assert_equal(a['b'].sum(), 0)
+
+
+class TestDivision:
+    def test_division_int(self):
+        # int division should follow Python
+        x = np.array([5, 10, 90, 100, -5, -10, -90, -100, -120])
+        if 5 / 10 == 0.5:
+            assert_equal(x / 100, [0.05, 0.1, 0.9, 1,
+                                   -0.05, -0.1, -0.9, -1, -1.2])
+        else:
+            assert_equal(x / 100, [0, 0, 0, 1, -1, -1, -1, -1, -2])
+        assert_equal(x // 100, [0, 0, 0, 1, -1, -1, -1, -1, -2])
+        assert_equal(x % 100, [5, 10, 90, 0, 95, 90, 10, 0, 80])
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    @pytest.mark.parametrize("dtype,ex_val", itertools.product(
+        np.sctypes['int'] + np.sctypes['uint'], (
+            (
+                # dividend
+                "np.array(range(fo.max-lsize, fo.max)).astype(dtype),"
+                # divisors
+                "np.arange(lsize).astype(dtype),"
+                # scalar divisors
+                "range(15)"
+            ),
+            (
+                # dividend
+                "np.arange(fo.min, fo.min+lsize).astype(dtype),"
+                # divisors
+                "np.arange(lsize//-2, lsize//2).astype(dtype),"
+                # scalar divisors
+                "range(fo.min, fo.min + 15)"
+            ), (
+                # dividend
+                "np.array(range(fo.max-lsize, fo.max)).astype(dtype),"
+                # divisors
+                "np.arange(lsize).astype(dtype),"
+                # scalar divisors
+                "[1,3,9,13,neg, fo.min+1, fo.min//2, fo.max//3, fo.max//4]"
+            )
+        )
+    ))
+    def test_division_int_boundary(self, dtype, ex_val):
+        fo = np.iinfo(dtype)
+        neg = -1 if fo.min < 0 else 1
+        # Large enough to test SIMD loops and remainder elements
+        lsize = 512 + 7
+        a, b, divisors = eval(ex_val)
+        a_lst, b_lst = a.tolist(), b.tolist()
+
+        c_div = lambda n, d: (
+            0 if d == 0 else (
+                fo.min if (n and n == fo.min and d == -1) else n//d
+            )
+        )
+        with np.errstate(divide='ignore'):
+            ac = a.copy()
+            ac //= b
+            div_ab = a // b
+        div_lst = [c_div(x, y) for x, y in zip(a_lst, b_lst)]
+
+        msg = "Integer arrays floor division check (//)"
+        assert all(div_ab == div_lst), msg
+        msg_eq = "Integer arrays floor division check (//=)"
+        assert all(ac == div_lst), msg_eq
+
+        for divisor in divisors:
+            ac = a.copy()
+            with np.errstate(divide='ignore', over='ignore'):
+                div_a = a // divisor
+                ac //= divisor
+            div_lst = [c_div(i, divisor) for i in a_lst]
+
+            assert all(div_a == div_lst), msg
+            assert all(ac == div_lst), msg_eq
+
+        with np.errstate(divide='raise', over='raise'):
+            if 0 in b:
+                # Verify overflow case
+                with pytest.raises(FloatingPointError,
+                        match="divide by zero encountered in floor_divide"):
+                    a // b
+            else:
+                a // b
+            if fo.min and fo.min in a:
+                with pytest.raises(FloatingPointError,
+                        match='overflow encountered in floor_divide'):
+                    a // -1
+            elif fo.min:
+                a // -1
+            with pytest.raises(FloatingPointError,
+                    match="divide by zero encountered in floor_divide"):
+                a // 0
+            with pytest.raises(FloatingPointError,
+                    match="divide by zero encountered in floor_divide"):
+                ac = a.copy()
+                ac //= 0
+
+            np.array([], dtype=dtype) // 0
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    @pytest.mark.parametrize("dtype,ex_val", itertools.product(
+        np.sctypes['int'] + np.sctypes['uint'], (
+            "np.array([fo.max, 1, 2, 1, 1, 2, 3], dtype=dtype)",
+            "np.array([fo.min, 1, -2, 1, 1, 2, -3]).astype(dtype)",
+            "np.arange(fo.min, fo.min+(100*10), 10, dtype=dtype)",
+            "np.array(range(fo.max-(100*7), fo.max, 7)).astype(dtype)",
+        )
+    ))
+    def test_division_int_reduce(self, dtype, ex_val):
+        fo = np.iinfo(dtype)
+        a = eval(ex_val)
+        lst = a.tolist()
+        c_div = lambda n, d: (
+            0 if d == 0 or (n and n == fo.min and d == -1) else n//d
+        )
+
+        with np.errstate(divide='ignore'):
+            div_a = np.floor_divide.reduce(a)
+        div_lst = reduce(c_div, lst)
+        msg = "Reduce floor integer division check"
+        assert div_a == div_lst, msg
+
+        with np.errstate(divide='raise', over='raise'):
+            with pytest.raises(FloatingPointError,
+                    match="divide by zero encountered in reduce"):
+                np.floor_divide.reduce(np.arange(-100, 100).astype(dtype))
+            if fo.min:
+                with pytest.raises(FloatingPointError,
+                        match='overflow encountered in reduce'):
+                    np.floor_divide.reduce(
+                        np.array([fo.min, 1, -1], dtype=dtype)
+                    )
+
+    @pytest.mark.parametrize(
+            "dividend,divisor,quotient",
+            [(np.timedelta64(2,'Y'), np.timedelta64(2,'M'), 12),
+             (np.timedelta64(2,'Y'), np.timedelta64(-2,'M'), -12),
+             (np.timedelta64(-2,'Y'), np.timedelta64(2,'M'), -12),
+             (np.timedelta64(-2,'Y'), np.timedelta64(-2,'M'), 12),
+             (np.timedelta64(2,'M'), np.timedelta64(-2,'Y'), -1),
+             (np.timedelta64(2,'Y'), np.timedelta64(0,'M'), 0),
+             (np.timedelta64(2,'Y'), 2, np.timedelta64(1,'Y')),
+             (np.timedelta64(2,'Y'), -2, np.timedelta64(-1,'Y')),
+             (np.timedelta64(-2,'Y'), 2, np.timedelta64(-1,'Y')),
+             (np.timedelta64(-2,'Y'), -2, np.timedelta64(1,'Y')),
+             (np.timedelta64(-2,'Y'), -2, np.timedelta64(1,'Y')),
+             (np.timedelta64(-2,'Y'), -3, np.timedelta64(0,'Y')),
+             (np.timedelta64(-2,'Y'), 0, np.timedelta64('Nat','Y')),
+            ])
+    def test_division_int_timedelta(self, dividend, divisor, quotient):
+        # If either divisor is 0 or quotient is Nat, check for division by 0
+        if divisor and (isinstance(quotient, int) or not np.isnat(quotient)):
+            msg = "Timedelta floor division check"
+            assert dividend // divisor == quotient, msg
+
+            # Test for arrays as well
+            msg = "Timedelta arrays floor division check"
+            dividend_array = np.array([dividend]*5)
+            quotient_array = np.array([quotient]*5)
+            assert all(dividend_array // divisor == quotient_array), msg
+        else:
+            if IS_WASM:
+                pytest.skip("fp errors don't work in wasm")
+            with np.errstate(divide='raise', invalid='raise'):
+                with pytest.raises(FloatingPointError):
+                    dividend // divisor
+
+    def test_division_complex(self):
+        # check that implementation is correct
+        msg = "Complex division implementation check"
+        x = np.array([1. + 1.*1j, 1. + .5*1j, 1. + 2.*1j], dtype=np.complex128)
+        assert_almost_equal(x**2/x, x, err_msg=msg)
+        # check overflow, underflow
+        msg = "Complex division overflow/underflow check"
+        x = np.array([1.e+110, 1.e-110], dtype=np.complex128)
+        y = x**2/x
+        assert_almost_equal(y/x, [1, 1], err_msg=msg)
+
+    def test_zero_division_complex(self):
+        with np.errstate(invalid="ignore", divide="ignore"):
+            x = np.array([0.0], dtype=np.complex128)
+            y = 1.0/x
+            assert_(np.isinf(y)[0])
+            y = complex(np.inf, np.nan)/x
+            assert_(np.isinf(y)[0])
+            y = complex(np.nan, np.inf)/x
+            assert_(np.isinf(y)[0])
+            y = complex(np.inf, np.inf)/x
+            assert_(np.isinf(y)[0])
+            y = 0.0/x
+            assert_(np.isnan(y)[0])
+
+    def test_floor_division_complex(self):
+        # check that floor division, divmod and remainder raises type errors
+        x = np.array([.9 + 1j, -.1 + 1j, .9 + .5*1j, .9 + 2.*1j], dtype=np.complex128)
+        with pytest.raises(TypeError):
+            x // 7
+        with pytest.raises(TypeError):
+            np.divmod(x, 7)
+        with pytest.raises(TypeError):
+            np.remainder(x, 7)
+
+    def test_floor_division_signed_zero(self):
+        # Check that the sign bit is correctly set when dividing positive and
+        # negative zero by one.
+        x = np.zeros(10)
+        assert_equal(np.signbit(x//1), 0)
+        assert_equal(np.signbit((-x)//1), 1)
+
+    @pytest.mark.skipif(hasattr(np.__config__, "blas_ssl2_info"),
+            reason="gh-22982")
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    @pytest.mark.parametrize('dtype', np.typecodes['Float'])
+    def test_floor_division_errors(self, dtype):
+        fnan = np.array(np.nan, dtype=dtype)
+        fone = np.array(1.0, dtype=dtype)
+        fzer = np.array(0.0, dtype=dtype)
+        finf = np.array(np.inf, dtype=dtype)
+        # divide by zero error check
+        with np.errstate(divide='raise', invalid='ignore'):
+            assert_raises(FloatingPointError, np.floor_divide, fone, fzer)
+        with np.errstate(divide='ignore', invalid='raise'):
+            np.floor_divide(fone, fzer)
+
+        # The following already contain a NaN and should not warn
+        with np.errstate(all='raise'):
+            np.floor_divide(fnan, fone)
+            np.floor_divide(fone, fnan)
+            np.floor_divide(fnan, fzer)
+            np.floor_divide(fzer, fnan)
+
+    @pytest.mark.parametrize('dtype', np.typecodes['Float'])
+    def test_floor_division_corner_cases(self, dtype):
+        # test corner cases like 1.0//0.0 for errors and return vals
+        x = np.zeros(10, dtype=dtype)
+        y = np.ones(10, dtype=dtype)
+        fnan = np.array(np.nan, dtype=dtype)
+        fone = np.array(1.0, dtype=dtype)
+        fzer = np.array(0.0, dtype=dtype)
+        finf = np.array(np.inf, dtype=dtype)
+        with suppress_warnings() as sup:
+            sup.filter(RuntimeWarning, "invalid value encountered in floor_divide")
+            div = np.floor_divide(fnan, fone)
+            assert(np.isnan(div)), "dt: %s, div: %s" % (dt, div)
+            div = np.floor_divide(fone, fnan)
+            assert(np.isnan(div)), "dt: %s, div: %s" % (dt, div)
+            div = np.floor_divide(fnan, fzer)
+            assert(np.isnan(div)), "dt: %s, div: %s" % (dt, div)
+        # verify 1.0//0.0 computations return inf
+        with np.errstate(divide='ignore'):
+            z = np.floor_divide(y, x)
+            assert_(np.isinf(z).all())
+
+def floor_divide_and_remainder(x, y):
+    return (np.floor_divide(x, y), np.remainder(x, y))
+
+
+def _signs(dt):
+    if dt in np.typecodes['UnsignedInteger']:
+        return (+1,)
+    else:
+        return (+1, -1)
+
+
+class TestRemainder:
+
+    def test_remainder_basic(self):
+        dt = np.typecodes['AllInteger'] + np.typecodes['Float']
+        for op in [floor_divide_and_remainder, np.divmod]:
+            for dt1, dt2 in itertools.product(dt, dt):
+                for sg1, sg2 in itertools.product(_signs(dt1), _signs(dt2)):
+                    fmt = 'op: %s, dt1: %s, dt2: %s, sg1: %s, sg2: %s'
+                    msg = fmt % (op.__name__, dt1, dt2, sg1, sg2)
+                    a = np.array(sg1*71, dtype=dt1)
+                    b = np.array(sg2*19, dtype=dt2)
+                    div, rem = op(a, b)
+                    assert_equal(div*b + rem, a, err_msg=msg)
+                    if sg2 == -1:
+                        assert_(b < rem <= 0, msg)
+                    else:
+                        assert_(b > rem >= 0, msg)
+
+    def test_float_remainder_exact(self):
+        # test that float results are exact for small integers. This also
+        # holds for the same integers scaled by powers of two.
+        nlst = list(range(-127, 0))
+        plst = list(range(1, 128))
+        dividend = nlst + [0] + plst
+        divisor = nlst + plst
+        arg = list(itertools.product(dividend, divisor))
+        tgt = list(divmod(*t) for t in arg)
+
+        a, b = np.array(arg, dtype=int).T
+        # convert exact integer results from Python to float so that
+        # signed zero can be used, it is checked.
+        tgtdiv, tgtrem = np.array(tgt, dtype=float).T
+        tgtdiv = np.where((tgtdiv == 0.0) & ((b < 0) ^ (a < 0)), -0.0, tgtdiv)
+        tgtrem = np.where((tgtrem == 0.0) & (b < 0), -0.0, tgtrem)
+
+        for op in [floor_divide_and_remainder, np.divmod]:
+            for dt in np.typecodes['Float']:
+                msg = 'op: %s, dtype: %s' % (op.__name__, dt)
+                fa = a.astype(dt)
+                fb = b.astype(dt)
+                div, rem = op(fa, fb)
+                assert_equal(div, tgtdiv, err_msg=msg)
+                assert_equal(rem, tgtrem, err_msg=msg)
+
+    def test_float_remainder_roundoff(self):
+        # gh-6127
+        dt = np.typecodes['Float']
+        for op in [floor_divide_and_remainder, np.divmod]:
+            for dt1, dt2 in itertools.product(dt, dt):
+                for sg1, sg2 in itertools.product((+1, -1), (+1, -1)):
+                    fmt = 'op: %s, dt1: %s, dt2: %s, sg1: %s, sg2: %s'
+                    msg = fmt % (op.__name__, dt1, dt2, sg1, sg2)
+                    a = np.array(sg1*78*6e-8, dtype=dt1)
+                    b = np.array(sg2*6e-8, dtype=dt2)
+                    div, rem = op(a, b)
+                    # Equal assertion should hold when fmod is used
+                    assert_equal(div*b + rem, a, err_msg=msg)
+                    if sg2 == -1:
+                        assert_(b < rem <= 0, msg)
+                    else:
+                        assert_(b > rem >= 0, msg)
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    @pytest.mark.xfail(sys.platform.startswith("darwin"),
+            reason="MacOS seems to not give the correct 'invalid' warning for "
+                   "`fmod`.  Hopefully, others always do.")
+    @pytest.mark.parametrize('dtype', np.typecodes['Float'])
+    def test_float_divmod_errors(self, dtype):
+        # Check valid errors raised for divmod and remainder
+        fzero = np.array(0.0, dtype=dtype)
+        fone = np.array(1.0, dtype=dtype)
+        finf = np.array(np.inf, dtype=dtype)
+        fnan = np.array(np.nan, dtype=dtype)
+        # since divmod is combination of both remainder and divide
+        # ops it will set both dividebyzero and invalid flags
+        with np.errstate(divide='raise', invalid='ignore'):
+            assert_raises(FloatingPointError, np.divmod, fone, fzero)
+        with np.errstate(divide='ignore', invalid='raise'):
+            assert_raises(FloatingPointError, np.divmod, fone, fzero)
+        with np.errstate(invalid='raise'):
+            assert_raises(FloatingPointError, np.divmod, fzero, fzero)
+        with np.errstate(invalid='raise'):
+            assert_raises(FloatingPointError, np.divmod, finf, finf)
+        with np.errstate(divide='ignore', invalid='raise'):
+            assert_raises(FloatingPointError, np.divmod, finf, fzero)
+        with np.errstate(divide='raise', invalid='ignore'):
+            # inf / 0 does not set any flags, only the modulo creates a NaN
+            np.divmod(finf, fzero)
+
+    @pytest.mark.skipif(hasattr(np.__config__, "blas_ssl2_info"),
+            reason="gh-22982")
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    @pytest.mark.xfail(sys.platform.startswith("darwin"),
+           reason="MacOS seems to not give the correct 'invalid' warning for "
+                  "`fmod`.  Hopefully, others always do.")
+    @pytest.mark.parametrize('dtype', np.typecodes['Float'])
+    @pytest.mark.parametrize('fn', [np.fmod, np.remainder])
+    def test_float_remainder_errors(self, dtype, fn):
+        fzero = np.array(0.0, dtype=dtype)
+        fone = np.array(1.0, dtype=dtype)
+        finf = np.array(np.inf, dtype=dtype)
+        fnan = np.array(np.nan, dtype=dtype)
+
+        # The following already contain a NaN and should not warn.
+        with np.errstate(all='raise'):
+            with pytest.raises(FloatingPointError,
+                    match="invalid value"):
+                fn(fone, fzero)
+            fn(fnan, fzero)
+            fn(fzero, fnan)
+            fn(fone, fnan)
+            fn(fnan, fone)
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    def test_float_remainder_overflow(self):
+        a = np.finfo(np.float64).tiny
+        with np.errstate(over='ignore', invalid='ignore'):
+            div, mod = np.divmod(4, a)
+            np.isinf(div)
+            assert_(mod == 0)
+        with np.errstate(over='raise', invalid='ignore'):
+            assert_raises(FloatingPointError, np.divmod, 4, a)
+        with np.errstate(invalid='raise', over='ignore'):
+            assert_raises(FloatingPointError, np.divmod, 4, a)
+
+    def test_float_divmod_corner_cases(self):
+        # check nan cases
+        for dt in np.typecodes['Float']:
+            fnan = np.array(np.nan, dtype=dt)
+            fone = np.array(1.0, dtype=dt)
+            fzer = np.array(0.0, dtype=dt)
+            finf = np.array(np.inf, dtype=dt)
+            with suppress_warnings() as sup:
+                sup.filter(RuntimeWarning, "invalid value encountered in divmod")
+                sup.filter(RuntimeWarning, "divide by zero encountered in divmod")
+                div, rem = np.divmod(fone, fzer)
+                assert(np.isinf(div)), 'dt: %s, div: %s' % (dt, rem)
+                assert(np.isnan(rem)), 'dt: %s, rem: %s' % (dt, rem)
+                div, rem = np.divmod(fzer, fzer)
+                assert(np.isnan(rem)), 'dt: %s, rem: %s' % (dt, rem)
+                assert_(np.isnan(div)), 'dt: %s, rem: %s' % (dt, rem)
+                div, rem = np.divmod(finf, finf)
+                assert(np.isnan(div)), 'dt: %s, rem: %s' % (dt, rem)
+                assert(np.isnan(rem)), 'dt: %s, rem: %s' % (dt, rem)
+                div, rem = np.divmod(finf, fzer)
+                assert(np.isinf(div)), 'dt: %s, rem: %s' % (dt, rem)
+                assert(np.isnan(rem)), 'dt: %s, rem: %s' % (dt, rem)
+                div, rem = np.divmod(fnan, fone)
+                assert(np.isnan(rem)), "dt: %s, rem: %s" % (dt, rem)
+                assert(np.isnan(div)), "dt: %s, rem: %s" % (dt, rem)
+                div, rem = np.divmod(fone, fnan)
+                assert(np.isnan(rem)), "dt: %s, rem: %s" % (dt, rem)
+                assert(np.isnan(div)), "dt: %s, rem: %s" % (dt, rem)
+                div, rem = np.divmod(fnan, fzer)
+                assert(np.isnan(rem)), "dt: %s, rem: %s" % (dt, rem)
+                assert(np.isnan(div)), "dt: %s, rem: %s" % (dt, rem)
+
+    def test_float_remainder_corner_cases(self):
+        # Check remainder magnitude.
+        for dt in np.typecodes['Float']:
+            fone = np.array(1.0, dtype=dt)
+            fzer = np.array(0.0, dtype=dt)
+            fnan = np.array(np.nan, dtype=dt)
+            b = np.array(1.0, dtype=dt)
+            a = np.nextafter(np.array(0.0, dtype=dt), -b)
+            rem = np.remainder(a, b)
+            assert_(rem <= b, 'dt: %s' % dt)
+            rem = np.remainder(-a, -b)
+            assert_(rem >= -b, 'dt: %s' % dt)
+
+        # Check nans, inf
+        with suppress_warnings() as sup:
+            sup.filter(RuntimeWarning, "invalid value encountered in remainder")
+            sup.filter(RuntimeWarning, "invalid value encountered in fmod")
+            for dt in np.typecodes['Float']:
+                fone = np.array(1.0, dtype=dt)
+                fzer = np.array(0.0, dtype=dt)
+                finf = np.array(np.inf, dtype=dt)
+                fnan = np.array(np.nan, dtype=dt)
+                rem = np.remainder(fone, fzer)
+                assert_(np.isnan(rem), 'dt: %s, rem: %s' % (dt, rem))
+                # MSVC 2008 returns NaN here, so disable the check.
+                #rem = np.remainder(fone, finf)
+                #assert_(rem == fone, 'dt: %s, rem: %s' % (dt, rem))
+                rem = np.remainder(finf, fone)
+                fmod = np.fmod(finf, fone)
+                assert_(np.isnan(fmod), 'dt: %s, fmod: %s' % (dt, fmod))
+                assert_(np.isnan(rem), 'dt: %s, rem: %s' % (dt, rem))
+                rem = np.remainder(finf, finf)
+                fmod = np.fmod(finf, fone)
+                assert_(np.isnan(rem), 'dt: %s, rem: %s' % (dt, rem))
+                assert_(np.isnan(fmod), 'dt: %s, fmod: %s' % (dt, fmod))
+                rem = np.remainder(finf, fzer)
+                fmod = np.fmod(finf, fzer)
+                assert_(np.isnan(rem), 'dt: %s, rem: %s' % (dt, rem))
+                assert_(np.isnan(fmod), 'dt: %s, fmod: %s' % (dt, fmod))
+                rem = np.remainder(fone, fnan)
+                fmod = np.fmod(fone, fnan)
+                assert_(np.isnan(rem), 'dt: %s, rem: %s' % (dt, rem))
+                assert_(np.isnan(fmod), 'dt: %s, fmod: %s' % (dt, fmod))
+                rem = np.remainder(fnan, fzer)
+                fmod = np.fmod(fnan, fzer)
+                assert_(np.isnan(rem), 'dt: %s, rem: %s' % (dt, rem))
+                assert_(np.isnan(fmod), 'dt: %s, fmod: %s' % (dt, rem))
+                rem = np.remainder(fnan, fone)
+                fmod = np.fmod(fnan, fone)
+                assert_(np.isnan(rem), 'dt: %s, rem: %s' % (dt, rem))
+                assert_(np.isnan(fmod), 'dt: %s, fmod: %s' % (dt, rem))
+
+
+class TestDivisionIntegerOverflowsAndDivideByZero:
+    result_type = namedtuple('result_type',
+            ['nocast', 'casted'])
+    helper_lambdas = {
+        'zero': lambda dtype: 0,
+        'min': lambda dtype: np.iinfo(dtype).min,
+        'neg_min': lambda dtype: -np.iinfo(dtype).min,
+        'min-zero': lambda dtype: (np.iinfo(dtype).min, 0),
+        'neg_min-zero': lambda dtype: (-np.iinfo(dtype).min, 0),
+    }
+    overflow_results = {
+        np.remainder: result_type(
+            helper_lambdas['zero'], helper_lambdas['zero']),
+        np.fmod: result_type(
+            helper_lambdas['zero'], helper_lambdas['zero']),
+        operator.mod: result_type(
+            helper_lambdas['zero'], helper_lambdas['zero']),
+        operator.floordiv: result_type(
+            helper_lambdas['min'], helper_lambdas['neg_min']),
+        np.floor_divide: result_type(
+            helper_lambdas['min'], helper_lambdas['neg_min']),
+        np.divmod: result_type(
+            helper_lambdas['min-zero'], helper_lambdas['neg_min-zero'])
+    }
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    @pytest.mark.parametrize("dtype", np.typecodes["Integer"])
+    def test_signed_division_overflow(self, dtype):
+        to_check = interesting_binop_operands(np.iinfo(dtype).min, -1, dtype)
+        for op1, op2, extractor, operand_identifier in to_check:
+            with pytest.warns(RuntimeWarning, match="overflow encountered"):
+                res = op1 // op2
+
+            assert res.dtype == op1.dtype
+            assert extractor(res) == np.iinfo(op1.dtype).min
+
+            # Remainder is well defined though, and does not warn:
+            res = op1 % op2
+            assert res.dtype == op1.dtype
+            assert extractor(res) == 0
+            # Check fmod as well:
+            res = np.fmod(op1, op2)
+            assert extractor(res) == 0
+
+            # Divmod warns for the division part:
+            with pytest.warns(RuntimeWarning, match="overflow encountered"):
+                res1, res2 = np.divmod(op1, op2)
+
+            assert res1.dtype == res2.dtype == op1.dtype
+            assert extractor(res1) == np.iinfo(op1.dtype).min
+            assert extractor(res2) == 0
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    @pytest.mark.parametrize("dtype", np.typecodes["AllInteger"])
+    def test_divide_by_zero(self, dtype):
+        # Note that the return value cannot be well defined here, but NumPy
+        # currently uses 0 consistently.  This could be changed.
+        to_check = interesting_binop_operands(1, 0, dtype)
+        for op1, op2, extractor, operand_identifier in to_check:
+            with pytest.warns(RuntimeWarning, match="divide by zero"):
+                res = op1 // op2
+
+            assert res.dtype == op1.dtype
+            assert extractor(res) == 0
+
+            with pytest.warns(RuntimeWarning, match="divide by zero"):
+                res1, res2 = np.divmod(op1, op2)
+
+            assert res1.dtype == res2.dtype == op1.dtype
+            assert extractor(res1) == 0
+            assert extractor(res2) == 0
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    @pytest.mark.parametrize("dividend_dtype",
+            np.sctypes['int'])
+    @pytest.mark.parametrize("divisor_dtype",
+            np.sctypes['int'])
+    @pytest.mark.parametrize("operation",
+            [np.remainder, np.fmod, np.divmod, np.floor_divide,
+             operator.mod, operator.floordiv])
+    @np.errstate(divide='warn', over='warn')
+    def test_overflows(self, dividend_dtype, divisor_dtype, operation):
+        # SIMD tries to perform the operation on as many elements as possible
+        # that is a multiple of the register's size. We resort to the
+        # default implementation for the leftover elements.
+        # We try to cover all paths here.
+        arrays = [np.array([np.iinfo(dividend_dtype).min]*i,
+                           dtype=dividend_dtype) for i in range(1, 129)]
+        divisor = np.array([-1], dtype=divisor_dtype)
+        # If dividend is a larger type than the divisor (`else` case),
+        # then, result will be a larger type than dividend and will not
+        # result in an overflow for `divmod` and `floor_divide`.
+        if np.dtype(dividend_dtype).itemsize >= np.dtype(
+                divisor_dtype).itemsize and operation in (
+                        np.divmod, np.floor_divide, operator.floordiv):
+            with pytest.warns(
+                    RuntimeWarning,
+                    match="overflow encountered in"):
+                result = operation(
+                            dividend_dtype(np.iinfo(dividend_dtype).min),
+                            divisor_dtype(-1)
+                        )
+                assert result == self.overflow_results[operation].nocast(
+                        dividend_dtype)
+
+            # Arrays
+            for a in arrays:
+                # In case of divmod, we need to flatten the result
+                # column first as we get a column vector of quotient and
+                # remainder and a normal flatten of the expected result.
+                with pytest.warns(
+                        RuntimeWarning,
+                        match="overflow encountered in"):
+                    result = np.array(operation(a, divisor)).flatten('f')
+                    expected_array = np.array(
+                            [self.overflow_results[operation].nocast(
+                                dividend_dtype)]*len(a)).flatten()
+                    assert_array_equal(result, expected_array)
+        else:
+            # Scalars
+            result = operation(
+                        dividend_dtype(np.iinfo(dividend_dtype).min),
+                        divisor_dtype(-1)
+                    )
+            assert result == self.overflow_results[operation].casted(
+                    dividend_dtype)
+
+            # Arrays
+            for a in arrays:
+                # See above comment on flatten
+                result = np.array(operation(a, divisor)).flatten('f')
+                expected_array = np.array(
+                        [self.overflow_results[operation].casted(
+                            dividend_dtype)]*len(a)).flatten()
+                assert_array_equal(result, expected_array)
+
+
+class TestCbrt:
+    def test_cbrt_scalar(self):
+        assert_almost_equal((np.cbrt(np.float32(-2.5)**3)), -2.5)
+
+    def test_cbrt(self):
+        x = np.array([1., 2., -3., np.inf, -np.inf])
+        assert_almost_equal(np.cbrt(x**3), x)
+
+        assert_(np.isnan(np.cbrt(np.nan)))
+        assert_equal(np.cbrt(np.inf), np.inf)
+        assert_equal(np.cbrt(-np.inf), -np.inf)
+
+
+class TestPower:
+    def test_power_float(self):
+        x = np.array([1., 2., 3.])
+        assert_equal(x**0, [1., 1., 1.])
+        assert_equal(x**1, x)
+        assert_equal(x**2, [1., 4., 9.])
+        y = x.copy()
+        y **= 2
+        assert_equal(y, [1., 4., 9.])
+        assert_almost_equal(x**(-1), [1., 0.5, 1./3])
+        assert_almost_equal(x**(0.5), [1., ncu.sqrt(2), ncu.sqrt(3)])
+
+        for out, inp, msg in _gen_alignment_data(dtype=np.float32,
+                                                 type='unary',
+                                                 max_size=11):
+            exp = [ncu.sqrt(i) for i in inp]
+            assert_almost_equal(inp**(0.5), exp, err_msg=msg)
+            np.sqrt(inp, out=out)
+            assert_equal(out, exp, err_msg=msg)
+
+        for out, inp, msg in _gen_alignment_data(dtype=np.float64,
+                                                 type='unary',
+                                                 max_size=7):
+            exp = [ncu.sqrt(i) for i in inp]
+            assert_almost_equal(inp**(0.5), exp, err_msg=msg)
+            np.sqrt(inp, out=out)
+            assert_equal(out, exp, err_msg=msg)
+
+    def test_power_complex(self):
+        x = np.array([1+2j, 2+3j, 3+4j])
+        assert_equal(x**0, [1., 1., 1.])
+        assert_equal(x**1, x)
+        assert_almost_equal(x**2, [-3+4j, -5+12j, -7+24j])
+        assert_almost_equal(x**3, [(1+2j)**3, (2+3j)**3, (3+4j)**3])
+        assert_almost_equal(x**4, [(1+2j)**4, (2+3j)**4, (3+4j)**4])
+        assert_almost_equal(x**(-1), [1/(1+2j), 1/(2+3j), 1/(3+4j)])
+        assert_almost_equal(x**(-2), [1/(1+2j)**2, 1/(2+3j)**2, 1/(3+4j)**2])
+        assert_almost_equal(x**(-3), [(-11+2j)/125, (-46-9j)/2197,
+                                      (-117-44j)/15625])
+        assert_almost_equal(x**(0.5), [ncu.sqrt(1+2j), ncu.sqrt(2+3j),
+                                       ncu.sqrt(3+4j)])
+        norm = 1./((x**14)[0])
+        assert_almost_equal(x**14 * norm,
+                [i * norm for i in [-76443+16124j, 23161315+58317492j,
+                                    5583548873 + 2465133864j]])
+
+        # Ticket #836
+        def assert_complex_equal(x, y):
+            assert_array_equal(x.real, y.real)
+            assert_array_equal(x.imag, y.imag)
+
+        for z in [complex(0, np.inf), complex(1, np.inf)]:
+            z = np.array([z], dtype=np.complex_)
+            with np.errstate(invalid="ignore"):
+                assert_complex_equal(z**1, z)
+                assert_complex_equal(z**2, z*z)
+                assert_complex_equal(z**3, z*z*z)
+
+    def test_power_zero(self):
+        # ticket #1271
+        zero = np.array([0j])
+        one = np.array([1+0j])
+        cnan = np.array([complex(np.nan, np.nan)])
+        # FIXME cinf not tested.
+        #cinf = np.array([complex(np.inf, 0)])
+
+        def assert_complex_equal(x, y):
+            x, y = np.asarray(x), np.asarray(y)
+            assert_array_equal(x.real, y.real)
+            assert_array_equal(x.imag, y.imag)
+
+        # positive powers
+        for p in [0.33, 0.5, 1, 1.5, 2, 3, 4, 5, 6.6]:
+            assert_complex_equal(np.power(zero, p), zero)
+
+        # zero power
+        assert_complex_equal(np.power(zero, 0), one)
+        with np.errstate(invalid="ignore"):
+            assert_complex_equal(np.power(zero, 0+1j), cnan)
+
+            # negative power
+            for p in [0.33, 0.5, 1, 1.5, 2, 3, 4, 5, 6.6]:
+                assert_complex_equal(np.power(zero, -p), cnan)
+            assert_complex_equal(np.power(zero, -1+0.2j), cnan)
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    def test_zero_power_nonzero(self):
+        # Testing 0^{Non-zero} issue 18378
+        zero = np.array([0.0+0.0j])
+        cnan = np.array([complex(np.nan, np.nan)])
+
+        def assert_complex_equal(x, y):
+            assert_array_equal(x.real, y.real)
+            assert_array_equal(x.imag, y.imag)
+
+        #Complex powers with positive real part will not generate a warning
+        assert_complex_equal(np.power(zero, 1+4j), zero)
+        assert_complex_equal(np.power(zero, 2-3j), zero)
+        #Testing zero values when real part is greater than zero
+        assert_complex_equal(np.power(zero, 1+1j), zero)
+        assert_complex_equal(np.power(zero, 1+0j), zero)
+        assert_complex_equal(np.power(zero, 1-1j), zero)
+        #Complex powers will negative real part or 0 (provided imaginary
+        # part is not zero) will generate a NAN and hence a RUNTIME warning
+        with pytest.warns(expected_warning=RuntimeWarning) as r:
+            assert_complex_equal(np.power(zero, -1+1j), cnan)
+            assert_complex_equal(np.power(zero, -2-3j), cnan)
+            assert_complex_equal(np.power(zero, -7+0j), cnan)
+            assert_complex_equal(np.power(zero, 0+1j), cnan)
+            assert_complex_equal(np.power(zero, 0-1j), cnan)
+        assert len(r) == 5
+
+    def test_fast_power(self):
+        x = np.array([1, 2, 3], np.int16)
+        res = x**2.0
+        assert_((x**2.00001).dtype is res.dtype)
+        assert_array_equal(res, [1, 4, 9])
+        # check the inplace operation on the casted copy doesn't mess with x
+        assert_(not np.may_share_memory(res, x))
+        assert_array_equal(x, [1, 2, 3])
+
+        # Check that the fast path ignores 1-element not 0-d arrays
+        res = x ** np.array([[[2]]])
+        assert_equal(res.shape, (1, 1, 3))
+
+    def test_integer_power(self):
+        a = np.array([15, 15], 'i8')
+        b = np.power(a, a)
+        assert_equal(b, [437893890380859375, 437893890380859375])
+
+    def test_integer_power_with_integer_zero_exponent(self):
+        dtypes = np.typecodes['Integer']
+        for dt in dtypes:
+            arr = np.arange(-10, 10, dtype=dt)
+            assert_equal(np.power(arr, 0), np.ones_like(arr))
+
+        dtypes = np.typecodes['UnsignedInteger']
+        for dt in dtypes:
+            arr = np.arange(10, dtype=dt)
+            assert_equal(np.power(arr, 0), np.ones_like(arr))
+
+    def test_integer_power_of_1(self):
+        dtypes = np.typecodes['AllInteger']
+        for dt in dtypes:
+            arr = np.arange(10, dtype=dt)
+            assert_equal(np.power(1, arr), np.ones_like(arr))
+
+    def test_integer_power_of_zero(self):
+        dtypes = np.typecodes['AllInteger']
+        for dt in dtypes:
+            arr = np.arange(1, 10, dtype=dt)
+            assert_equal(np.power(0, arr), np.zeros_like(arr))
+
+    def test_integer_to_negative_power(self):
+        dtypes = np.typecodes['Integer']
+        for dt in dtypes:
+            a = np.array([0, 1, 2, 3], dtype=dt)
+            b = np.array([0, 1, 2, -3], dtype=dt)
+            one = np.array(1, dtype=dt)
+            minusone = np.array(-1, dtype=dt)
+            assert_raises(ValueError, np.power, a, b)
+            assert_raises(ValueError, np.power, a, minusone)
+            assert_raises(ValueError, np.power, one, b)
+            assert_raises(ValueError, np.power, one, minusone)
+
+    def test_float_to_inf_power(self):
+        for dt in [np.float32, np.float64]:
+            a = np.array([1, 1, 2, 2, -2, -2, np.inf, -np.inf], dt)
+            b = np.array([np.inf, -np.inf, np.inf, -np.inf,
+                                np.inf, -np.inf, np.inf, -np.inf], dt)
+            r = np.array([1, 1, np.inf, 0, np.inf, 0, np.inf, 0], dt)
+            assert_equal(np.power(a, b), r)
+
+
+class TestFloat_power:
+    def test_type_conversion(self):
+        arg_type = '?bhilBHILefdgFDG'
+        res_type = 'ddddddddddddgDDG'
+        for dtin, dtout in zip(arg_type, res_type):
+            msg = "dtin: %s, dtout: %s" % (dtin, dtout)
+            arg = np.ones(1, dtype=dtin)
+            res = np.float_power(arg, arg)
+            assert_(res.dtype.name == np.dtype(dtout).name, msg)
+
+
+class TestLog2:
+    @pytest.mark.parametrize('dt', ['f', 'd', 'g'])
+    def test_log2_values(self, dt):
+        x = [1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024]
+        y = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+        xf = np.array(x, dtype=dt)
+        yf = np.array(y, dtype=dt)
+        assert_almost_equal(np.log2(xf), yf)
+
+    @pytest.mark.parametrize("i", range(1, 65))
+    def test_log2_ints(self, i):
+        # a good log2 implementation should provide this,
+        # might fail on OS with bad libm
+        v = np.log2(2.**i)
+        assert_equal(v, float(i), err_msg='at exponent %d' % i)
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    def test_log2_special(self):
+        assert_equal(np.log2(1.), 0.)
+        assert_equal(np.log2(np.inf), np.inf)
+        assert_(np.isnan(np.log2(np.nan)))
+
+        with warnings.catch_warnings(record=True) as w:
+            warnings.filterwarnings('always', '', RuntimeWarning)
+            assert_(np.isnan(np.log2(-1.)))
+            assert_(np.isnan(np.log2(-np.inf)))
+            assert_equal(np.log2(0.), -np.inf)
+            assert_(w[0].category is RuntimeWarning)
+            assert_(w[1].category is RuntimeWarning)
+            assert_(w[2].category is RuntimeWarning)
+
+
+class TestExp2:
+    def test_exp2_values(self):
+        x = [1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024]
+        y = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+        for dt in ['f', 'd', 'g']:
+            xf = np.array(x, dtype=dt)
+            yf = np.array(y, dtype=dt)
+            assert_almost_equal(np.exp2(yf), xf)
+
+
+class TestLogAddExp2(_FilterInvalids):
+    # Need test for intermediate precisions
+    def test_logaddexp2_values(self):
+        x = [1, 2, 3, 4, 5]
+        y = [5, 4, 3, 2, 1]
+        z = [6, 6, 6, 6, 6]
+        for dt, dec_ in zip(['f', 'd', 'g'], [6, 15, 15]):
+            xf = np.log2(np.array(x, dtype=dt))
+            yf = np.log2(np.array(y, dtype=dt))
+            zf = np.log2(np.array(z, dtype=dt))
+            assert_almost_equal(np.logaddexp2(xf, yf), zf, decimal=dec_)
+
+    def test_logaddexp2_range(self):
+        x = [1000000, -1000000, 1000200, -1000200]
+        y = [1000200, -1000200, 1000000, -1000000]
+        z = [1000200, -1000000, 1000200, -1000000]
+        for dt in ['f', 'd', 'g']:
+            logxf = np.array(x, dtype=dt)
+            logyf = np.array(y, dtype=dt)
+            logzf = np.array(z, dtype=dt)
+            assert_almost_equal(np.logaddexp2(logxf, logyf), logzf)
+
+    def test_inf(self):
+        inf = np.inf
+        x = [inf, -inf,  inf, -inf, inf, 1,  -inf,  1]
+        y = [inf,  inf, -inf, -inf, 1,   inf, 1,   -inf]
+        z = [inf,  inf,  inf, -inf, inf, inf, 1,    1]
+        with np.errstate(invalid='raise'):
+            for dt in ['f', 'd', 'g']:
+                logxf = np.array(x, dtype=dt)
+                logyf = np.array(y, dtype=dt)
+                logzf = np.array(z, dtype=dt)
+                assert_equal(np.logaddexp2(logxf, logyf), logzf)
+
+    def test_nan(self):
+        assert_(np.isnan(np.logaddexp2(np.nan, np.inf)))
+        assert_(np.isnan(np.logaddexp2(np.inf, np.nan)))
+        assert_(np.isnan(np.logaddexp2(np.nan, 0)))
+        assert_(np.isnan(np.logaddexp2(0, np.nan)))
+        assert_(np.isnan(np.logaddexp2(np.nan, np.nan)))
+
+    def test_reduce(self):
+        assert_equal(np.logaddexp2.identity, -np.inf)
+        assert_equal(np.logaddexp2.reduce([]), -np.inf)
+        assert_equal(np.logaddexp2.reduce([-np.inf]), -np.inf)
+        assert_equal(np.logaddexp2.reduce([-np.inf, 0]), 0)
+
+
+class TestLog:
+    def test_log_values(self):
+        x = [1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024]
+        y = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+        for dt in ['f', 'd', 'g']:
+            log2_ = 0.69314718055994530943
+            xf = np.array(x, dtype=dt)
+            yf = np.array(y, dtype=dt)*log2_
+            assert_almost_equal(np.log(xf), yf)
+
+        # test aliasing(issue #17761)
+        x = np.array([2, 0.937500, 3, 0.947500, 1.054697])
+        xf = np.log(x)
+        assert_almost_equal(np.log(x, out=x), xf)
+
+        # test log() of max for dtype does not raise
+        for dt in ['f', 'd', 'g']:
+            try:
+                with np.errstate(all='raise'):
+                    x = np.finfo(dt).max
+                    np.log(x)
+            except FloatingPointError as exc:
+                if dt == 'g' and IS_MUSL:
+                    # FloatingPointError is known to occur on longdouble
+                    # for musllinux_x86_64 x is very large
+                    pytest.skip(
+                        "Overflow has occurred for"
+                        " np.log(np.finfo(np.longdouble).max)"
+                    )
+                else:
+                    raise exc
+
+    def test_log_strides(self):
+        np.random.seed(42)
+        strides = np.array([-4,-3,-2,-1,1,2,3,4])
+        sizes = np.arange(2,100)
+        for ii in sizes:
+            x_f64 = np.float64(np.random.uniform(low=0.01, high=100.0,size=ii))
+            x_special = x_f64.copy()
+            x_special[3:-1:4] = 1.0
+            y_true = np.log(x_f64)
+            y_special = np.log(x_special)
+            for jj in strides:
+                assert_array_almost_equal_nulp(np.log(x_f64[::jj]), y_true[::jj], nulp=2)
+                assert_array_almost_equal_nulp(np.log(x_special[::jj]), y_special[::jj], nulp=2)
+
+class TestExp:
+    def test_exp_values(self):
+        x = [1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024]
+        y = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+        for dt in ['f', 'd', 'g']:
+            log2_ = 0.69314718055994530943
+            xf = np.array(x, dtype=dt)
+            yf = np.array(y, dtype=dt)*log2_
+            assert_almost_equal(np.exp(yf), xf)
+
+    def test_exp_strides(self):
+        np.random.seed(42)
+        strides = np.array([-4,-3,-2,-1,1,2,3,4])
+        sizes = np.arange(2,100)
+        for ii in sizes:
+            x_f64 = np.float64(np.random.uniform(low=0.01, high=709.1,size=ii))
+            y_true = np.exp(x_f64)
+            for jj in strides:
+                assert_array_almost_equal_nulp(np.exp(x_f64[::jj]), y_true[::jj], nulp=2)
+
+class TestSpecialFloats:
+    def test_exp_values(self):
+        with np.errstate(under='raise', over='raise'):
+            x = [np.nan,  np.nan, np.inf, 0.]
+            y = [np.nan, -np.nan, np.inf, -np.inf]
+            for dt in ['e', 'f', 'd', 'g']:
+                xf = np.array(x, dtype=dt)
+                yf = np.array(y, dtype=dt)
+                assert_equal(np.exp(yf), xf)
+
+    # See: https://github.com/numpy/numpy/issues/19192
+    @pytest.mark.xfail(
+        _glibc_older_than("2.17"),
+        reason="Older glibc versions may not raise appropriate FP exceptions"
+    )
+    def test_exp_exceptions(self):
+        with np.errstate(over='raise'):
+            assert_raises(FloatingPointError, np.exp, np.float16(11.0899))
+            assert_raises(FloatingPointError, np.exp, np.float32(100.))
+            assert_raises(FloatingPointError, np.exp, np.float32(1E19))
+            assert_raises(FloatingPointError, np.exp, np.float64(800.))
+            assert_raises(FloatingPointError, np.exp, np.float64(1E19))
+
+        with np.errstate(under='raise'):
+            assert_raises(FloatingPointError, np.exp, np.float16(-17.5))
+            assert_raises(FloatingPointError, np.exp, np.float32(-1000.))
+            assert_raises(FloatingPointError, np.exp, np.float32(-1E19))
+            assert_raises(FloatingPointError, np.exp, np.float64(-1000.))
+            assert_raises(FloatingPointError, np.exp, np.float64(-1E19))
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    def test_log_values(self):
+        with np.errstate(all='ignore'):
+            x = [np.nan, np.nan, np.inf, np.nan, -np.inf, np.nan]
+            y = [np.nan, -np.nan, np.inf, -np.inf, 0.0, -1.0]
+            y1p = [np.nan, -np.nan, np.inf, -np.inf, -1.0, -2.0]
+            for dt in ['e', 'f', 'd', 'g']:
+                xf = np.array(x, dtype=dt)
+                yf = np.array(y, dtype=dt)
+                yf1p = np.array(y1p, dtype=dt)
+                assert_equal(np.log(yf), xf)
+                assert_equal(np.log2(yf), xf)
+                assert_equal(np.log10(yf), xf)
+                assert_equal(np.log1p(yf1p), xf)
+
+        with np.errstate(divide='raise'):
+            for dt in ['e', 'f', 'd']:
+                assert_raises(FloatingPointError, np.log,
+                              np.array(0.0, dtype=dt))
+                assert_raises(FloatingPointError, np.log2,
+                              np.array(0.0, dtype=dt))
+                assert_raises(FloatingPointError, np.log10,
+                              np.array(0.0, dtype=dt))
+                assert_raises(FloatingPointError, np.log1p,
+                              np.array(-1.0, dtype=dt))
+
+        with np.errstate(invalid='raise'):
+            for dt in ['e', 'f', 'd']:
+                assert_raises(FloatingPointError, np.log,
+                              np.array(-np.inf, dtype=dt))
+                assert_raises(FloatingPointError, np.log,
+                              np.array(-1.0, dtype=dt))
+                assert_raises(FloatingPointError, np.log2,
+                              np.array(-np.inf, dtype=dt))
+                assert_raises(FloatingPointError, np.log2,
+                              np.array(-1.0, dtype=dt))
+                assert_raises(FloatingPointError, np.log10,
+                              np.array(-np.inf, dtype=dt))
+                assert_raises(FloatingPointError, np.log10,
+                              np.array(-1.0, dtype=dt))
+                assert_raises(FloatingPointError, np.log1p,
+                              np.array(-np.inf, dtype=dt))
+                assert_raises(FloatingPointError, np.log1p,
+                              np.array(-2.0, dtype=dt))
+
+        # See https://github.com/numpy/numpy/issues/18005
+        with assert_no_warnings():
+            a = np.array(1e9, dtype='float32')
+            np.log(a)
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    @pytest.mark.parametrize('dtype', ['e', 'f', 'd', 'g'])
+    def test_sincos_values(self, dtype):
+        with np.errstate(all='ignore'):
+            x = [np.nan, np.nan, np.nan, np.nan]
+            y = [np.nan, -np.nan, np.inf, -np.inf]
+            xf = np.array(x, dtype=dtype)
+            yf = np.array(y, dtype=dtype)
+            assert_equal(np.sin(yf), xf)
+            assert_equal(np.cos(yf), xf)
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    @pytest.mark.xfail(
+        sys.platform.startswith("darwin"),
+        reason="underflow is triggered for scalar 'sin'"
+    )
+    def test_sincos_underflow(self):
+        with np.errstate(under='raise'):
+            underflow_trigger = np.array(
+                float.fromhex("0x1.f37f47a03f82ap-511"),
+                dtype=np.float64
+            )
+            np.sin(underflow_trigger)
+            np.cos(underflow_trigger)
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    @pytest.mark.parametrize('callable', [np.sin, np.cos])
+    @pytest.mark.parametrize('dtype', ['e', 'f', 'd'])
+    @pytest.mark.parametrize('value', [np.inf, -np.inf])
+    def test_sincos_errors(self, callable, dtype, value):
+        with np.errstate(invalid='raise'):
+            assert_raises(FloatingPointError, callable,
+                np.array([value], dtype=dtype))
+
+    @pytest.mark.parametrize('callable', [np.sin, np.cos])
+    @pytest.mark.parametrize('dtype', ['f', 'd'])
+    @pytest.mark.parametrize('stride', [-1, 1, 2, 4, 5])
+    def test_sincos_overlaps(self, callable, dtype, stride):
+        N = 100
+        M = N // abs(stride)
+        rng = np.random.default_rng(42)
+        x = rng.standard_normal(N, dtype)
+        y = callable(x[::stride])
+        callable(x[::stride], out=x[:M])
+        assert_equal(x[:M], y)
+
+    @pytest.mark.parametrize('dt', ['e', 'f', 'd', 'g'])
+    def test_sqrt_values(self, dt):
+        with np.errstate(all='ignore'):
+            x = [np.nan, np.nan, np.inf, np.nan, 0.]
+            y = [np.nan, -np.nan, np.inf, -np.inf, 0.]
+            xf = np.array(x, dtype=dt)
+            yf = np.array(y, dtype=dt)
+            assert_equal(np.sqrt(yf), xf)
+
+        # with np.errstate(invalid='raise'):
+        #     assert_raises(
+        #         FloatingPointError, np.sqrt, np.array(-100., dtype=dt)
+        #     )
+
+    def test_abs_values(self):
+        x = [np.nan,  np.nan, np.inf, np.inf, 0., 0., 1.0, 1.0]
+        y = [np.nan, -np.nan, np.inf, -np.inf, 0., -0., -1.0, 1.0]
+        for dt in ['e', 'f', 'd', 'g']:
+            xf = np.array(x, dtype=dt)
+            yf = np.array(y, dtype=dt)
+            assert_equal(np.abs(yf), xf)
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    def test_square_values(self):
+        x = [np.nan,  np.nan, np.inf, np.inf]
+        y = [np.nan, -np.nan, np.inf, -np.inf]
+        with np.errstate(all='ignore'):
+            for dt in ['e', 'f', 'd', 'g']:
+                xf = np.array(x, dtype=dt)
+                yf = np.array(y, dtype=dt)
+                assert_equal(np.square(yf), xf)
+
+        with np.errstate(over='raise'):
+            assert_raises(FloatingPointError, np.square,
+                          np.array(1E3, dtype='e'))
+            assert_raises(FloatingPointError, np.square,
+                          np.array(1E32, dtype='f'))
+            assert_raises(FloatingPointError, np.square,
+                          np.array(1E200, dtype='d'))
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    def test_reciprocal_values(self):
+        with np.errstate(all='ignore'):
+            x = [np.nan,  np.nan, 0.0, -0.0, np.inf, -np.inf]
+            y = [np.nan, -np.nan, np.inf, -np.inf, 0., -0.]
+            for dt in ['e', 'f', 'd', 'g']:
+                xf = np.array(x, dtype=dt)
+                yf = np.array(y, dtype=dt)
+                assert_equal(np.reciprocal(yf), xf)
+
+        with np.errstate(divide='raise'):
+            for dt in ['e', 'f', 'd', 'g']:
+                assert_raises(FloatingPointError, np.reciprocal,
+                              np.array(-0.0, dtype=dt))
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    def test_tan(self):
+        with np.errstate(all='ignore'):
+            in_ = [np.nan, -np.nan, 0.0, -0.0, np.inf, -np.inf]
+            out = [np.nan, np.nan, 0.0, -0.0, np.nan, np.nan]
+            for dt in ['e', 'f', 'd']:
+                in_arr = np.array(in_, dtype=dt)
+                out_arr = np.array(out, dtype=dt)
+                assert_equal(np.tan(in_arr), out_arr)
+
+        with np.errstate(invalid='raise'):
+            for dt in ['e', 'f', 'd']:
+                assert_raises(FloatingPointError, np.tan,
+                              np.array(np.inf, dtype=dt))
+                assert_raises(FloatingPointError, np.tan,
+                              np.array(-np.inf, dtype=dt))
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    def test_arcsincos(self):
+        with np.errstate(all='ignore'):
+            in_ = [np.nan, -np.nan, np.inf, -np.inf]
+            out = [np.nan, np.nan, np.nan, np.nan]
+            for dt in ['e', 'f', 'd']:
+                in_arr = np.array(in_, dtype=dt)
+                out_arr = np.array(out, dtype=dt)
+                assert_equal(np.arcsin(in_arr), out_arr)
+                assert_equal(np.arccos(in_arr), out_arr)
+
+        for callable in [np.arcsin, np.arccos]:
+            for value in [np.inf, -np.inf, 2.0, -2.0]:
+                for dt in ['e', 'f', 'd']:
+                    with np.errstate(invalid='raise'):
+                        assert_raises(FloatingPointError, callable,
+                                      np.array(value, dtype=dt))
+
+    def test_arctan(self):
+        with np.errstate(all='ignore'):
+            in_ = [np.nan, -np.nan]
+            out = [np.nan, np.nan]
+            for dt in ['e', 'f', 'd']:
+                in_arr = np.array(in_, dtype=dt)
+                out_arr = np.array(out, dtype=dt)
+                assert_equal(np.arctan(in_arr), out_arr)
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    def test_sinh(self):
+        in_ = [np.nan, -np.nan, np.inf, -np.inf]
+        out = [np.nan, np.nan, np.inf, -np.inf]
+        for dt in ['e', 'f', 'd']:
+            in_arr = np.array(in_, dtype=dt)
+            out_arr = np.array(out, dtype=dt)
+            assert_equal(np.sinh(in_arr), out_arr)
+
+        with np.errstate(over='raise'):
+            assert_raises(FloatingPointError, np.sinh,
+                          np.array(12.0, dtype='e'))
+            assert_raises(FloatingPointError, np.sinh,
+                          np.array(120.0, dtype='f'))
+            assert_raises(FloatingPointError, np.sinh,
+                          np.array(1200.0, dtype='d'))
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    @pytest.mark.skipif('bsd' in sys.platform,
+            reason="fallback implementation may not raise, see gh-2487")
+    def test_cosh(self):
+        in_ = [np.nan, -np.nan, np.inf, -np.inf]
+        out = [np.nan, np.nan, np.inf, np.inf]
+        for dt in ['e', 'f', 'd']:
+            in_arr = np.array(in_, dtype=dt)
+            out_arr = np.array(out, dtype=dt)
+            assert_equal(np.cosh(in_arr), out_arr)
+
+        with np.errstate(over='raise'):
+            assert_raises(FloatingPointError, np.cosh,
+                          np.array(12.0, dtype='e'))
+            assert_raises(FloatingPointError, np.cosh,
+                          np.array(120.0, dtype='f'))
+            assert_raises(FloatingPointError, np.cosh,
+                          np.array(1200.0, dtype='d'))
+
+    def test_tanh(self):
+        in_ = [np.nan, -np.nan, np.inf, -np.inf]
+        out = [np.nan, np.nan, 1.0, -1.0]
+        for dt in ['e', 'f', 'd']:
+            in_arr = np.array(in_, dtype=dt)
+            out_arr = np.array(out, dtype=dt)
+            assert_equal(np.tanh(in_arr), out_arr)
+
+    def test_arcsinh(self):
+        in_ = [np.nan, -np.nan, np.inf, -np.inf]
+        out = [np.nan, np.nan, np.inf, -np.inf]
+        for dt in ['e', 'f', 'd']:
+            in_arr = np.array(in_, dtype=dt)
+            out_arr = np.array(out, dtype=dt)
+            assert_equal(np.arcsinh(in_arr), out_arr)
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    def test_arccosh(self):
+        with np.errstate(all='ignore'):
+            in_ = [np.nan, -np.nan, np.inf, -np.inf, 1.0, 0.0]
+            out = [np.nan, np.nan, np.inf, np.nan, 0.0, np.nan]
+            for dt in ['e', 'f', 'd']:
+                in_arr = np.array(in_, dtype=dt)
+                out_arr = np.array(out, dtype=dt)
+                assert_equal(np.arccosh(in_arr), out_arr)
+
+        for value in [0.0, -np.inf]:
+            with np.errstate(invalid='raise'):
+                for dt in ['e', 'f', 'd']:
+                    assert_raises(FloatingPointError, np.arccosh,
+                                  np.array(value, dtype=dt))
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    def test_arctanh(self):
+        with np.errstate(all='ignore'):
+            in_ = [np.nan, -np.nan, np.inf, -np.inf, 1.0, -1.0, 2.0]
+            out = [np.nan, np.nan, np.nan, np.nan, np.inf, -np.inf, np.nan]
+            for dt in ['e', 'f', 'd']:
+                in_arr = np.array(in_, dtype=dt)
+                out_arr = np.array(out, dtype=dt)
+                assert_equal(np.arctanh(in_arr), out_arr)
+
+        for value in [1.01, np.inf, -np.inf, 1.0, -1.0]:
+            with np.errstate(invalid='raise', divide='raise'):
+                for dt in ['e', 'f', 'd']:
+                    assert_raises(FloatingPointError, np.arctanh,
+                                  np.array(value, dtype=dt))
+
+        # Make sure glibc < 2.18 atanh is not used, issue 25087
+        assert np.signbit(np.arctanh(-1j).real)
+
+    # See: https://github.com/numpy/numpy/issues/20448
+    @pytest.mark.xfail(
+        _glibc_older_than("2.17"),
+        reason="Older glibc versions may not raise appropriate FP exceptions"
+    )
+    def test_exp2(self):
+        with np.errstate(all='ignore'):
+            in_ = [np.nan, -np.nan, np.inf, -np.inf]
+            out = [np.nan, np.nan, np.inf, 0.0]
+            for dt in ['e', 'f', 'd']:
+                in_arr = np.array(in_, dtype=dt)
+                out_arr = np.array(out, dtype=dt)
+                assert_equal(np.exp2(in_arr), out_arr)
+
+        for value in [2000.0, -2000.0]:
+            with np.errstate(over='raise', under='raise'):
+                for dt in ['e', 'f', 'd']:
+                    assert_raises(FloatingPointError, np.exp2,
+                                  np.array(value, dtype=dt))
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    def test_expm1(self):
+        with np.errstate(all='ignore'):
+            in_ = [np.nan, -np.nan, np.inf, -np.inf]
+            out = [np.nan, np.nan, np.inf, -1.0]
+            for dt in ['e', 'f', 'd']:
+                in_arr = np.array(in_, dtype=dt)
+                out_arr = np.array(out, dtype=dt)
+                assert_equal(np.expm1(in_arr), out_arr)
+
+        for value in [200.0, 2000.0]:
+            with np.errstate(over='raise'):
+                for dt in ['e', 'f']:
+                    assert_raises(FloatingPointError, np.expm1,
+                                  np.array(value, dtype=dt))
+
+    # test to ensure no spurious FP exceptions are raised due to SIMD
+    INF_INVALID_ERR = [
+        np.cos, np.sin, np.tan, np.arccos, np.arcsin, np.spacing, np.arctanh
+    ]
+    NEG_INVALID_ERR = [
+        np.log, np.log2, np.log10, np.log1p, np.sqrt, np.arccosh,
+        np.arctanh
+    ]
+    ONE_INVALID_ERR = [
+        np.arctanh,
+    ]
+    LTONE_INVALID_ERR = [
+        np.arccosh,
+    ]
+    BYZERO_ERR = [
+        np.log, np.log2, np.log10, np.reciprocal, np.arccosh
+    ]
+
+    @pytest.mark.skipif(sys.platform == "win32" and sys.maxsize < 2**31 + 1,
+                        reason='failures on 32-bit Python, see FIXME below')
+    @pytest.mark.parametrize("ufunc", UFUNCS_UNARY_FP)
+    @pytest.mark.parametrize("dtype", ('e', 'f', 'd'))
+    @pytest.mark.parametrize("data, escape", (
+        ([0.03], LTONE_INVALID_ERR),
+        ([0.03]*32, LTONE_INVALID_ERR),
+        # neg
+        ([-1.0], NEG_INVALID_ERR),
+        ([-1.0]*32, NEG_INVALID_ERR),
+        # flat
+        ([1.0], ONE_INVALID_ERR),
+        ([1.0]*32, ONE_INVALID_ERR),
+        # zero
+        ([0.0], BYZERO_ERR),
+        ([0.0]*32, BYZERO_ERR),
+        ([-0.0], BYZERO_ERR),
+        ([-0.0]*32, BYZERO_ERR),
+        # nan
+        ([0.5, 0.5, 0.5, np.nan], LTONE_INVALID_ERR),
+        ([0.5, 0.5, 0.5, np.nan]*32, LTONE_INVALID_ERR),
+        ([np.nan, 1.0, 1.0, 1.0], ONE_INVALID_ERR),
+        ([np.nan, 1.0, 1.0, 1.0]*32, ONE_INVALID_ERR),
+        ([np.nan], []),
+        ([np.nan]*32, []),
+        # inf
+        ([0.5, 0.5, 0.5, np.inf], INF_INVALID_ERR + LTONE_INVALID_ERR),
+        ([0.5, 0.5, 0.5, np.inf]*32, INF_INVALID_ERR + LTONE_INVALID_ERR),
+        ([np.inf, 1.0, 1.0, 1.0], INF_INVALID_ERR),
+        ([np.inf, 1.0, 1.0, 1.0]*32, INF_INVALID_ERR),
+        ([np.inf], INF_INVALID_ERR),
+        ([np.inf]*32, INF_INVALID_ERR),
+        # ninf
+        ([0.5, 0.5, 0.5, -np.inf],
+         NEG_INVALID_ERR + INF_INVALID_ERR + LTONE_INVALID_ERR),
+        ([0.5, 0.5, 0.5, -np.inf]*32,
+         NEG_INVALID_ERR + INF_INVALID_ERR + LTONE_INVALID_ERR),
+        ([-np.inf, 1.0, 1.0, 1.0], NEG_INVALID_ERR + INF_INVALID_ERR),
+        ([-np.inf, 1.0, 1.0, 1.0]*32, NEG_INVALID_ERR + INF_INVALID_ERR),
+        ([-np.inf], NEG_INVALID_ERR + INF_INVALID_ERR),
+        ([-np.inf]*32, NEG_INVALID_ERR + INF_INVALID_ERR),
+    ))
+    def test_unary_spurious_fpexception(self, ufunc, dtype, data, escape):
+        if escape and ufunc in escape:
+            return
+        # FIXME: NAN raises FP invalid exception:
+        #  - ceil/float16 on MSVC:32-bit
+        #  - spacing/float16 on almost all platforms
+        # FIXME: skipped on MSVC:32-bit during switch to Meson, 10 cases fail
+        #        when SIMD support not present / disabled
+        if ufunc in (np.spacing, np.ceil) and dtype == 'e':
+            return
+        array = np.array(data, dtype=dtype)
+        with assert_no_warnings():
+            ufunc(array)
+
+    @pytest.mark.parametrize("dtype", ('e', 'f', 'd'))
+    def test_divide_spurious_fpexception(self, dtype):
+        dt = np.dtype(dtype)
+        dt_info = np.finfo(dt)
+        subnorm = dt_info.smallest_subnormal
+        # Verify a bug fix caused due to filling the remaining lanes of the
+        # partially loaded dividend SIMD vector with ones, which leads to
+        # raising an overflow warning when the divisor is denormal.
+        # see https://github.com/numpy/numpy/issues/25097
+        with assert_no_warnings():
+            np.zeros(128 + 1, dtype=dt) / subnorm
+
+class TestFPClass:
+    @pytest.mark.parametrize("stride", [-5, -4, -3, -2, -1, 1,
+                                2, 4, 5, 6, 7, 8, 9, 10])
+    def test_fpclass(self, stride):
+        arr_f64 = np.array([np.nan, -np.nan, np.inf, -np.inf, -1.0, 1.0, -0.0, 0.0, 2.2251e-308, -2.2251e-308], dtype='d')
+        arr_f32 = np.array([np.nan, -np.nan, np.inf, -np.inf, -1.0, 1.0, -0.0, 0.0, 1.4013e-045, -1.4013e-045], dtype='f')
+        nan     = np.array([True, True, False, False, False, False, False, False, False, False])
+        inf     = np.array([False, False, True, True, False, False, False, False, False, False])
+        sign    = np.array([False, True, False, True, True, False, True, False, False, True])
+        finite  = np.array([False, False, False, False, True, True, True, True, True, True])
+        assert_equal(np.isnan(arr_f32[::stride]), nan[::stride])
+        assert_equal(np.isnan(arr_f64[::stride]), nan[::stride])
+        assert_equal(np.isinf(arr_f32[::stride]), inf[::stride])
+        assert_equal(np.isinf(arr_f64[::stride]), inf[::stride])
+        assert_equal(np.signbit(arr_f32[::stride]), sign[::stride])
+        assert_equal(np.signbit(arr_f64[::stride]), sign[::stride])
+        assert_equal(np.isfinite(arr_f32[::stride]), finite[::stride])
+        assert_equal(np.isfinite(arr_f64[::stride]), finite[::stride])
+
+    @pytest.mark.parametrize("dtype", ['d', 'f'])
+    def test_fp_noncontiguous(self, dtype):
+        data = np.array([np.nan, -np.nan, np.inf, -np.inf, -1.0,
+                            1.0, -0.0, 0.0, 2.2251e-308,
+                            -2.2251e-308], dtype=dtype)
+        nan = np.array([True, True, False, False, False, False,
+                            False, False, False, False])
+        inf = np.array([False, False, True, True, False, False,
+                            False, False, False, False])
+        sign = np.array([False, True, False, True, True, False,
+                            True, False, False, True])
+        finite = np.array([False, False, False, False, True, True,
+                            True, True, True, True])
+        out = np.ndarray(data.shape, dtype='bool')
+        ncontig_in = data[1::3]
+        ncontig_out = out[1::3]
+        contig_in = np.array(ncontig_in)
+        assert_equal(ncontig_in.flags.c_contiguous, False)
+        assert_equal(ncontig_out.flags.c_contiguous, False)
+        assert_equal(contig_in.flags.c_contiguous, True)
+        # ncontig in, ncontig out
+        assert_equal(np.isnan(ncontig_in, out=ncontig_out), nan[1::3])
+        assert_equal(np.isinf(ncontig_in, out=ncontig_out), inf[1::3])
+        assert_equal(np.signbit(ncontig_in, out=ncontig_out), sign[1::3])
+        assert_equal(np.isfinite(ncontig_in, out=ncontig_out), finite[1::3])
+        # contig in, ncontig out
+        assert_equal(np.isnan(contig_in, out=ncontig_out), nan[1::3])
+        assert_equal(np.isinf(contig_in, out=ncontig_out), inf[1::3])
+        assert_equal(np.signbit(contig_in, out=ncontig_out), sign[1::3])
+        assert_equal(np.isfinite(contig_in, out=ncontig_out), finite[1::3])
+        # ncontig in, contig out
+        assert_equal(np.isnan(ncontig_in), nan[1::3])
+        assert_equal(np.isinf(ncontig_in), inf[1::3])
+        assert_equal(np.signbit(ncontig_in), sign[1::3])
+        assert_equal(np.isfinite(ncontig_in), finite[1::3])
+        # contig in, contig out, nd stride
+        data_split = np.array(np.array_split(data, 2))
+        nan_split = np.array(np.array_split(nan, 2))
+        inf_split = np.array(np.array_split(inf, 2))
+        sign_split = np.array(np.array_split(sign, 2))
+        finite_split = np.array(np.array_split(finite, 2))
+        assert_equal(np.isnan(data_split), nan_split)
+        assert_equal(np.isinf(data_split), inf_split)
+        assert_equal(np.signbit(data_split), sign_split)
+        assert_equal(np.isfinite(data_split), finite_split)
+
+class TestLDExp:
+    @pytest.mark.parametrize("stride", [-4,-2,-1,1,2,4])
+    @pytest.mark.parametrize("dtype", ['f', 'd'])
+    def test_ldexp(self, dtype, stride):
+        mant = np.array([0.125, 0.25, 0.5, 1., 1., 2., 4., 8.], dtype=dtype)
+        exp  = np.array([3, 2, 1, 0, 0, -1, -2, -3], dtype='i')
+        out  = np.zeros(8, dtype=dtype)
+        assert_equal(np.ldexp(mant[::stride], exp[::stride], out=out[::stride]), np.ones(8, dtype=dtype)[::stride])
+        assert_equal(out[::stride], np.ones(8, dtype=dtype)[::stride])
+
+class TestFRExp:
+    @pytest.mark.parametrize("stride", [-4,-2,-1,1,2,4])
+    @pytest.mark.parametrize("dtype", ['f', 'd'])
+    @pytest.mark.xfail(IS_MUSL, reason="gh23048")
+    @pytest.mark.skipif(not sys.platform.startswith('linux'),
+                        reason="np.frexp gives different answers for NAN/INF on windows and linux")
+    def test_frexp(self, dtype, stride):
+        arr = np.array([np.nan, np.nan, np.inf, -np.inf, 0.0, -0.0, 1.0, -1.0], dtype=dtype)
+        mant_true = np.array([np.nan, np.nan, np.inf, -np.inf, 0.0, -0.0, 0.5, -0.5], dtype=dtype)
+        exp_true  = np.array([0, 0, 0, 0, 0, 0, 1, 1], dtype='i')
+        out_mant  = np.ones(8, dtype=dtype)
+        out_exp   = 2*np.ones(8, dtype='i')
+        mant, exp = np.frexp(arr[::stride], out=(out_mant[::stride], out_exp[::stride]))
+        assert_equal(mant_true[::stride], mant)
+        assert_equal(exp_true[::stride], exp)
+        assert_equal(out_mant[::stride], mant_true[::stride])
+        assert_equal(out_exp[::stride], exp_true[::stride])
+
+# func : [maxulperror, low, high]
+avx_ufuncs = {'sqrt'        :[1,  0.,   100.],
+              'absolute'    :[0, -100., 100.],
+              'reciprocal'  :[1,  1.,   100.],
+              'square'      :[1, -100., 100.],
+              'rint'        :[0, -100., 100.],
+              'floor'       :[0, -100., 100.],
+              'ceil'        :[0, -100., 100.],
+              'trunc'       :[0, -100., 100.]}
+
+class TestAVXUfuncs:
+    def test_avx_based_ufunc(self):
+        strides = np.array([-4,-3,-2,-1,1,2,3,4])
+        np.random.seed(42)
+        for func, prop in avx_ufuncs.items():
+            maxulperr = prop[0]
+            minval = prop[1]
+            maxval = prop[2]
+            # various array sizes to ensure masking in AVX is tested
+            for size in range(1,32):
+                myfunc = getattr(np, func)
+                x_f32 = np.float32(np.random.uniform(low=minval, high=maxval,
+                    size=size))
+                x_f64 = np.float64(x_f32)
+                x_f128 = np.longdouble(x_f32)
+                y_true128 = myfunc(x_f128)
+                if maxulperr == 0:
+                    assert_equal(myfunc(x_f32), np.float32(y_true128))
+                    assert_equal(myfunc(x_f64), np.float64(y_true128))
+                else:
+                    assert_array_max_ulp(myfunc(x_f32), np.float32(y_true128),
+                            maxulp=maxulperr)
+                    assert_array_max_ulp(myfunc(x_f64), np.float64(y_true128),
+                            maxulp=maxulperr)
+                # various strides to test gather instruction
+                if size > 1:
+                    y_true32 = myfunc(x_f32)
+                    y_true64 = myfunc(x_f64)
+                    for jj in strides:
+                        assert_equal(myfunc(x_f64[::jj]), y_true64[::jj])
+                        assert_equal(myfunc(x_f32[::jj]), y_true32[::jj])
+
+class TestAVXFloat32Transcendental:
+    def test_exp_float32(self):
+        np.random.seed(42)
+        x_f32 = np.float32(np.random.uniform(low=0.0,high=88.1,size=1000000))
+        x_f64 = np.float64(x_f32)
+        assert_array_max_ulp(np.exp(x_f32), np.float32(np.exp(x_f64)), maxulp=3)
+
+    def test_log_float32(self):
+        np.random.seed(42)
+        x_f32 = np.float32(np.random.uniform(low=0.0,high=1000,size=1000000))
+        x_f64 = np.float64(x_f32)
+        assert_array_max_ulp(np.log(x_f32), np.float32(np.log(x_f64)), maxulp=4)
+
+    def test_sincos_float32(self):
+        np.random.seed(42)
+        N = 1000000
+        M = np.int_(N/20)
+        index = np.random.randint(low=0, high=N, size=M)
+        x_f32 = np.float32(np.random.uniform(low=-100.,high=100.,size=N))
+        if not _glibc_older_than("2.17"):
+            # test coverage for elements > 117435.992f for which glibc is used
+            # this is known to be problematic on old glibc, so skip it there
+            x_f32[index] = np.float32(10E+10*np.random.rand(M))
+        x_f64 = np.float64(x_f32)
+        assert_array_max_ulp(np.sin(x_f32), np.float32(np.sin(x_f64)), maxulp=2)
+        assert_array_max_ulp(np.cos(x_f32), np.float32(np.cos(x_f64)), maxulp=2)
+        # test aliasing(issue #17761)
+        tx_f32 = x_f32.copy()
+        assert_array_max_ulp(np.sin(x_f32, out=x_f32), np.float32(np.sin(x_f64)), maxulp=2)
+        assert_array_max_ulp(np.cos(tx_f32, out=tx_f32), np.float32(np.cos(x_f64)), maxulp=2)
+
+    def test_strided_float32(self):
+        np.random.seed(42)
+        strides = np.array([-4,-3,-2,-1,1,2,3,4])
+        sizes = np.arange(2,100)
+        for ii in sizes:
+            x_f32 = np.float32(np.random.uniform(low=0.01,high=88.1,size=ii))
+            x_f32_large = x_f32.copy()
+            x_f32_large[3:-1:4] = 120000.0
+            exp_true = np.exp(x_f32)
+            log_true = np.log(x_f32)
+            sin_true = np.sin(x_f32_large)
+            cos_true = np.cos(x_f32_large)
+            for jj in strides:
+                assert_array_almost_equal_nulp(np.exp(x_f32[::jj]), exp_true[::jj], nulp=2)
+                assert_array_almost_equal_nulp(np.log(x_f32[::jj]), log_true[::jj], nulp=2)
+                assert_array_almost_equal_nulp(np.sin(x_f32_large[::jj]), sin_true[::jj], nulp=2)
+                assert_array_almost_equal_nulp(np.cos(x_f32_large[::jj]), cos_true[::jj], nulp=2)
+
+class TestLogAddExp(_FilterInvalids):
+    def test_logaddexp_values(self):
+        x = [1, 2, 3, 4, 5]
+        y = [5, 4, 3, 2, 1]
+        z = [6, 6, 6, 6, 6]
+        for dt, dec_ in zip(['f', 'd', 'g'], [6, 15, 15]):
+            xf = np.log(np.array(x, dtype=dt))
+            yf = np.log(np.array(y, dtype=dt))
+            zf = np.log(np.array(z, dtype=dt))
+            assert_almost_equal(np.logaddexp(xf, yf), zf, decimal=dec_)
+
+    def test_logaddexp_range(self):
+        x = [1000000, -1000000, 1000200, -1000200]
+        y = [1000200, -1000200, 1000000, -1000000]
+        z = [1000200, -1000000, 1000200, -1000000]
+        for dt in ['f', 'd', 'g']:
+            logxf = np.array(x, dtype=dt)
+            logyf = np.array(y, dtype=dt)
+            logzf = np.array(z, dtype=dt)
+            assert_almost_equal(np.logaddexp(logxf, logyf), logzf)
+
+    def test_inf(self):
+        inf = np.inf
+        x = [inf, -inf,  inf, -inf, inf, 1,  -inf,  1]
+        y = [inf,  inf, -inf, -inf, 1,   inf, 1,   -inf]
+        z = [inf,  inf,  inf, -inf, inf, inf, 1,    1]
+        with np.errstate(invalid='raise'):
+            for dt in ['f', 'd', 'g']:
+                logxf = np.array(x, dtype=dt)
+                logyf = np.array(y, dtype=dt)
+                logzf = np.array(z, dtype=dt)
+                assert_equal(np.logaddexp(logxf, logyf), logzf)
+
+    def test_nan(self):
+        assert_(np.isnan(np.logaddexp(np.nan, np.inf)))
+        assert_(np.isnan(np.logaddexp(np.inf, np.nan)))
+        assert_(np.isnan(np.logaddexp(np.nan, 0)))
+        assert_(np.isnan(np.logaddexp(0, np.nan)))
+        assert_(np.isnan(np.logaddexp(np.nan, np.nan)))
+
+    def test_reduce(self):
+        assert_equal(np.logaddexp.identity, -np.inf)
+        assert_equal(np.logaddexp.reduce([]), -np.inf)
+
+
+class TestLog1p:
+    def test_log1p(self):
+        assert_almost_equal(ncu.log1p(0.2), ncu.log(1.2))
+        assert_almost_equal(ncu.log1p(1e-6), ncu.log(1+1e-6))
+
+    def test_special(self):
+        with np.errstate(invalid="ignore", divide="ignore"):
+            assert_equal(ncu.log1p(np.nan), np.nan)
+            assert_equal(ncu.log1p(np.inf), np.inf)
+            assert_equal(ncu.log1p(-1.), -np.inf)
+            assert_equal(ncu.log1p(-2.), np.nan)
+            assert_equal(ncu.log1p(-np.inf), np.nan)
+
+
+class TestExpm1:
+    def test_expm1(self):
+        assert_almost_equal(ncu.expm1(0.2), ncu.exp(0.2)-1)
+        assert_almost_equal(ncu.expm1(1e-6), ncu.exp(1e-6)-1)
+
+    def test_special(self):
+        assert_equal(ncu.expm1(np.inf), np.inf)
+        assert_equal(ncu.expm1(0.), 0.)
+        assert_equal(ncu.expm1(-0.), -0.)
+        assert_equal(ncu.expm1(np.inf), np.inf)
+        assert_equal(ncu.expm1(-np.inf), -1.)
+
+    def test_complex(self):
+        x = np.asarray(1e-12)
+        assert_allclose(x, ncu.expm1(x))
+        x = x.astype(np.complex128)
+        assert_allclose(x, ncu.expm1(x))
+
+
+class TestHypot:
+    def test_simple(self):
+        assert_almost_equal(ncu.hypot(1, 1), ncu.sqrt(2))
+        assert_almost_equal(ncu.hypot(0, 0), 0)
+
+    def test_reduce(self):
+        assert_almost_equal(ncu.hypot.reduce([3.0, 4.0]), 5.0)
+        assert_almost_equal(ncu.hypot.reduce([3.0, 4.0, 0]), 5.0)
+        assert_almost_equal(ncu.hypot.reduce([9.0, 12.0, 20.0]), 25.0)
+        assert_equal(ncu.hypot.reduce([]), 0.0)
+
+
+def assert_hypot_isnan(x, y):
+    with np.errstate(invalid='ignore'):
+        assert_(np.isnan(ncu.hypot(x, y)),
+                "hypot(%s, %s) is %s, not nan" % (x, y, ncu.hypot(x, y)))
+
+
+def assert_hypot_isinf(x, y):
+    with np.errstate(invalid='ignore'):
+        assert_(np.isinf(ncu.hypot(x, y)),
+                "hypot(%s, %s) is %s, not inf" % (x, y, ncu.hypot(x, y)))
+
+
+class TestHypotSpecialValues:
+    def test_nan_outputs(self):
+        assert_hypot_isnan(np.nan, np.nan)
+        assert_hypot_isnan(np.nan, 1)
+
+    def test_nan_outputs2(self):
+        assert_hypot_isinf(np.nan, np.inf)
+        assert_hypot_isinf(np.inf, np.nan)
+        assert_hypot_isinf(np.inf, 0)
+        assert_hypot_isinf(0, np.inf)
+        assert_hypot_isinf(np.inf, np.inf)
+        assert_hypot_isinf(np.inf, 23.0)
+
+    def test_no_fpe(self):
+        assert_no_warnings(ncu.hypot, np.inf, 0)
+
+
+def assert_arctan2_isnan(x, y):
+    assert_(np.isnan(ncu.arctan2(x, y)), "arctan(%s, %s) is %s, not nan" % (x, y, ncu.arctan2(x, y)))
+
+
+def assert_arctan2_ispinf(x, y):
+    assert_((np.isinf(ncu.arctan2(x, y)) and ncu.arctan2(x, y) > 0), "arctan(%s, %s) is %s, not +inf" % (x, y, ncu.arctan2(x, y)))
+
+
+def assert_arctan2_isninf(x, y):
+    assert_((np.isinf(ncu.arctan2(x, y)) and ncu.arctan2(x, y) < 0), "arctan(%s, %s) is %s, not -inf" % (x, y, ncu.arctan2(x, y)))
+
+
+def assert_arctan2_ispzero(x, y):
+    assert_((ncu.arctan2(x, y) == 0 and not np.signbit(ncu.arctan2(x, y))), "arctan(%s, %s) is %s, not +0" % (x, y, ncu.arctan2(x, y)))
+
+
+def assert_arctan2_isnzero(x, y):
+    assert_((ncu.arctan2(x, y) == 0 and np.signbit(ncu.arctan2(x, y))), "arctan(%s, %s) is %s, not -0" % (x, y, ncu.arctan2(x, y)))
+
+
+class TestArctan2SpecialValues:
+    def test_one_one(self):
+        # atan2(1, 1) returns pi/4.
+        assert_almost_equal(ncu.arctan2(1, 1), 0.25 * np.pi)
+        assert_almost_equal(ncu.arctan2(-1, 1), -0.25 * np.pi)
+        assert_almost_equal(ncu.arctan2(1, -1), 0.75 * np.pi)
+
+    def test_zero_nzero(self):
+        # atan2(+-0, -0) returns +-pi.
+        assert_almost_equal(ncu.arctan2(np.PZERO, np.NZERO), np.pi)
+        assert_almost_equal(ncu.arctan2(np.NZERO, np.NZERO), -np.pi)
+
+    def test_zero_pzero(self):
+        # atan2(+-0, +0) returns +-0.
+        assert_arctan2_ispzero(np.PZERO, np.PZERO)
+        assert_arctan2_isnzero(np.NZERO, np.PZERO)
+
+    def test_zero_negative(self):
+        # atan2(+-0, x) returns +-pi for x < 0.
+        assert_almost_equal(ncu.arctan2(np.PZERO, -1), np.pi)
+        assert_almost_equal(ncu.arctan2(np.NZERO, -1), -np.pi)
+
+    def test_zero_positive(self):
+        # atan2(+-0, x) returns +-0 for x > 0.
+        assert_arctan2_ispzero(np.PZERO, 1)
+        assert_arctan2_isnzero(np.NZERO, 1)
+
+    def test_positive_zero(self):
+        # atan2(y, +-0) returns +pi/2 for y > 0.
+        assert_almost_equal(ncu.arctan2(1, np.PZERO), 0.5 * np.pi)
+        assert_almost_equal(ncu.arctan2(1, np.NZERO), 0.5 * np.pi)
+
+    def test_negative_zero(self):
+        # atan2(y, +-0) returns -pi/2 for y < 0.
+        assert_almost_equal(ncu.arctan2(-1, np.PZERO), -0.5 * np.pi)
+        assert_almost_equal(ncu.arctan2(-1, np.NZERO), -0.5 * np.pi)
+
+    def test_any_ninf(self):
+        # atan2(+-y, -infinity) returns +-pi for finite y > 0.
+        assert_almost_equal(ncu.arctan2(1, np.NINF),  np.pi)
+        assert_almost_equal(ncu.arctan2(-1, np.NINF), -np.pi)
+
+    def test_any_pinf(self):
+        # atan2(+-y, +infinity) returns +-0 for finite y > 0.
+        assert_arctan2_ispzero(1, np.inf)
+        assert_arctan2_isnzero(-1, np.inf)
+
+    def test_inf_any(self):
+        # atan2(+-infinity, x) returns +-pi/2 for finite x.
+        assert_almost_equal(ncu.arctan2( np.inf, 1),  0.5 * np.pi)
+        assert_almost_equal(ncu.arctan2(-np.inf, 1), -0.5 * np.pi)
+
+    def test_inf_ninf(self):
+        # atan2(+-infinity, -infinity) returns +-3*pi/4.
+        assert_almost_equal(ncu.arctan2( np.inf, -np.inf),  0.75 * np.pi)
+        assert_almost_equal(ncu.arctan2(-np.inf, -np.inf), -0.75 * np.pi)
+
+    def test_inf_pinf(self):
+        # atan2(+-infinity, +infinity) returns +-pi/4.
+        assert_almost_equal(ncu.arctan2( np.inf, np.inf),  0.25 * np.pi)
+        assert_almost_equal(ncu.arctan2(-np.inf, np.inf), -0.25 * np.pi)
+
+    def test_nan_any(self):
+        # atan2(nan, x) returns nan for any x, including inf
+        assert_arctan2_isnan(np.nan, np.inf)
+        assert_arctan2_isnan(np.inf, np.nan)
+        assert_arctan2_isnan(np.nan, np.nan)
+
+
+class TestLdexp:
+    def _check_ldexp(self, tp):
+        assert_almost_equal(ncu.ldexp(np.array(2., np.float32),
+                                      np.array(3, tp)), 16.)
+        assert_almost_equal(ncu.ldexp(np.array(2., np.float64),
+                                      np.array(3, tp)), 16.)
+        assert_almost_equal(ncu.ldexp(np.array(2., np.longdouble),
+                                      np.array(3, tp)), 16.)
+
+    def test_ldexp(self):
+        # The default Python int type should work
+        assert_almost_equal(ncu.ldexp(2., 3),  16.)
+        # The following int types should all be accepted
+        self._check_ldexp(np.int8)
+        self._check_ldexp(np.int16)
+        self._check_ldexp(np.int32)
+        self._check_ldexp('i')
+        self._check_ldexp('l')
+
+    def test_ldexp_overflow(self):
+        # silence warning emitted on overflow
+        with np.errstate(over="ignore"):
+            imax = np.iinfo(np.dtype('l')).max
+            imin = np.iinfo(np.dtype('l')).min
+            assert_equal(ncu.ldexp(2., imax), np.inf)
+            assert_equal(ncu.ldexp(2., imin), 0)
+
+
+class TestMaximum(_FilterInvalids):
+    def test_reduce(self):
+        dflt = np.typecodes['AllFloat']
+        dint = np.typecodes['AllInteger']
+        seq1 = np.arange(11)
+        seq2 = seq1[::-1]
+        func = np.maximum.reduce
+        for dt in dint:
+            tmp1 = seq1.astype(dt)
+            tmp2 = seq2.astype(dt)
+            assert_equal(func(tmp1), 10)
+            assert_equal(func(tmp2), 10)
+        for dt in dflt:
+            tmp1 = seq1.astype(dt)
+            tmp2 = seq2.astype(dt)
+            assert_equal(func(tmp1), 10)
+            assert_equal(func(tmp2), 10)
+            tmp1[::2] = np.nan
+            tmp2[::2] = np.nan
+            assert_equal(func(tmp1), np.nan)
+            assert_equal(func(tmp2), np.nan)
+
+    def test_reduce_complex(self):
+        assert_equal(np.maximum.reduce([1, 2j]), 1)
+        assert_equal(np.maximum.reduce([1+3j, 2j]), 1+3j)
+
+    def test_float_nans(self):
+        nan = np.nan
+        arg1 = np.array([0,   nan, nan])
+        arg2 = np.array([nan, 0,   nan])
+        out = np.array([nan, nan, nan])
+        assert_equal(np.maximum(arg1, arg2), out)
+
+    def test_object_nans(self):
+        # Multiple checks to give this a chance to
+        # fail if cmp is used instead of rich compare.
+        # Failure cannot be guaranteed.
+        for i in range(1):
+            x = np.array(float('nan'), object)
+            y = 1.0
+            z = np.array(float('nan'), object)
+            assert_(np.maximum(x, y) == 1.0)
+            assert_(np.maximum(z, y) == 1.0)
+
+    def test_complex_nans(self):
+        nan = np.nan
+        for cnan in [complex(nan, 0), complex(0, nan), complex(nan, nan)]:
+            arg1 = np.array([0, cnan, cnan], dtype=complex)
+            arg2 = np.array([cnan, 0, cnan], dtype=complex)
+            out = np.array([nan, nan, nan], dtype=complex)
+            assert_equal(np.maximum(arg1, arg2), out)
+
+    def test_object_array(self):
+        arg1 = np.arange(5, dtype=object)
+        arg2 = arg1 + 1
+        assert_equal(np.maximum(arg1, arg2), arg2)
+
+    def test_strided_array(self):
+        arr1 = np.array([-4.0, 1.0, 10.0,  0.0, np.nan, -np.nan, np.inf, -np.inf])
+        arr2 = np.array([-2.0,-1.0, np.nan, 1.0, 0.0,    np.nan, 1.0,    -3.0])
+        maxtrue  = np.array([-2.0, 1.0, np.nan, 1.0, np.nan, np.nan, np.inf, -3.0])
+        out = np.ones(8)
+        out_maxtrue = np.array([-2.0, 1.0, 1.0, 10.0, 1.0, 1.0, np.nan, 1.0])
+        assert_equal(np.maximum(arr1,arr2), maxtrue)
+        assert_equal(np.maximum(arr1[::2],arr2[::2]), maxtrue[::2])
+        assert_equal(np.maximum(arr1[:4:], arr2[::2]), np.array([-2.0, np.nan, 10.0, 1.0]))
+        assert_equal(np.maximum(arr1[::3], arr2[:3:]), np.array([-2.0, 0.0, np.nan]))
+        assert_equal(np.maximum(arr1[:6:2], arr2[::3], out=out[::3]), np.array([-2.0, 10., np.nan]))
+        assert_equal(out, out_maxtrue)
+
+    def test_precision(self):
+        dtypes = [np.float16, np.float32, np.float64, np.longdouble]
+
+        for dt in dtypes:
+            dtmin = np.finfo(dt).min
+            dtmax = np.finfo(dt).max
+            d1 = dt(0.1)
+            d1_next = np.nextafter(d1, np.inf)
+
+            test_cases = [
+                # v1    v2          expected
+                (dtmin, -np.inf,    dtmin),
+                (dtmax, -np.inf,    dtmax),
+                (d1,    d1_next,    d1_next),
+                (dtmax, np.nan,     np.nan),
+            ]
+
+            for v1, v2, expected in test_cases:
+                assert_equal(np.maximum([v1], [v2]), [expected])
+                assert_equal(np.maximum.reduce([v1, v2]), expected)
+
+
+class TestMinimum(_FilterInvalids):
+    def test_reduce(self):
+        dflt = np.typecodes['AllFloat']
+        dint = np.typecodes['AllInteger']
+        seq1 = np.arange(11)
+        seq2 = seq1[::-1]
+        func = np.minimum.reduce
+        for dt in dint:
+            tmp1 = seq1.astype(dt)
+            tmp2 = seq2.astype(dt)
+            assert_equal(func(tmp1), 0)
+            assert_equal(func(tmp2), 0)
+        for dt in dflt:
+            tmp1 = seq1.astype(dt)
+            tmp2 = seq2.astype(dt)
+            assert_equal(func(tmp1), 0)
+            assert_equal(func(tmp2), 0)
+            tmp1[::2] = np.nan
+            tmp2[::2] = np.nan
+            assert_equal(func(tmp1), np.nan)
+            assert_equal(func(tmp2), np.nan)
+
+    def test_reduce_complex(self):
+        assert_equal(np.minimum.reduce([1, 2j]), 2j)
+        assert_equal(np.minimum.reduce([1+3j, 2j]), 2j)
+
+    def test_float_nans(self):
+        nan = np.nan
+        arg1 = np.array([0,   nan, nan])
+        arg2 = np.array([nan, 0,   nan])
+        out = np.array([nan, nan, nan])
+        assert_equal(np.minimum(arg1, arg2), out)
+
+    def test_object_nans(self):
+        # Multiple checks to give this a chance to
+        # fail if cmp is used instead of rich compare.
+        # Failure cannot be guaranteed.
+        for i in range(1):
+            x = np.array(float('nan'), object)
+            y = 1.0
+            z = np.array(float('nan'), object)
+            assert_(np.minimum(x, y) == 1.0)
+            assert_(np.minimum(z, y) == 1.0)
+
+    def test_complex_nans(self):
+        nan = np.nan
+        for cnan in [complex(nan, 0), complex(0, nan), complex(nan, nan)]:
+            arg1 = np.array([0, cnan, cnan], dtype=complex)
+            arg2 = np.array([cnan, 0, cnan], dtype=complex)
+            out = np.array([nan, nan, nan], dtype=complex)
+            assert_equal(np.minimum(arg1, arg2), out)
+
+    def test_object_array(self):
+        arg1 = np.arange(5, dtype=object)
+        arg2 = arg1 + 1
+        assert_equal(np.minimum(arg1, arg2), arg1)
+
+    def test_strided_array(self):
+        arr1 = np.array([-4.0, 1.0, 10.0,  0.0, np.nan, -np.nan, np.inf, -np.inf])
+        arr2 = np.array([-2.0,-1.0, np.nan, 1.0, 0.0,    np.nan, 1.0,    -3.0])
+        mintrue  = np.array([-4.0, -1.0, np.nan, 0.0, np.nan, np.nan, 1.0, -np.inf])
+        out = np.ones(8)
+        out_mintrue = np.array([-4.0, 1.0, 1.0, 1.0, 1.0, 1.0, np.nan, 1.0])
+        assert_equal(np.minimum(arr1,arr2), mintrue)
+        assert_equal(np.minimum(arr1[::2],arr2[::2]), mintrue[::2])
+        assert_equal(np.minimum(arr1[:4:], arr2[::2]), np.array([-4.0, np.nan, 0.0, 0.0]))
+        assert_equal(np.minimum(arr1[::3], arr2[:3:]), np.array([-4.0, -1.0, np.nan]))
+        assert_equal(np.minimum(arr1[:6:2], arr2[::3], out=out[::3]), np.array([-4.0, 1.0, np.nan]))
+        assert_equal(out, out_mintrue)
+
+    def test_precision(self):
+        dtypes = [np.float16, np.float32, np.float64, np.longdouble]
+
+        for dt in dtypes:
+            dtmin = np.finfo(dt).min
+            dtmax = np.finfo(dt).max
+            d1 = dt(0.1)
+            d1_next = np.nextafter(d1, np.inf)
+
+            test_cases = [
+                # v1    v2          expected
+                (dtmin, np.inf,     dtmin),
+                (dtmax, np.inf,     dtmax),
+                (d1,    d1_next,    d1),
+                (dtmin, np.nan,     np.nan),
+            ]
+
+            for v1, v2, expected in test_cases:
+                assert_equal(np.minimum([v1], [v2]), [expected])
+                assert_equal(np.minimum.reduce([v1, v2]), expected)
+
+
+class TestFmax(_FilterInvalids):
+    def test_reduce(self):
+        dflt = np.typecodes['AllFloat']
+        dint = np.typecodes['AllInteger']
+        seq1 = np.arange(11)
+        seq2 = seq1[::-1]
+        func = np.fmax.reduce
+        for dt in dint:
+            tmp1 = seq1.astype(dt)
+            tmp2 = seq2.astype(dt)
+            assert_equal(func(tmp1), 10)
+            assert_equal(func(tmp2), 10)
+        for dt in dflt:
+            tmp1 = seq1.astype(dt)
+            tmp2 = seq2.astype(dt)
+            assert_equal(func(tmp1), 10)
+            assert_equal(func(tmp2), 10)
+            tmp1[::2] = np.nan
+            tmp2[::2] = np.nan
+            assert_equal(func(tmp1), 9)
+            assert_equal(func(tmp2), 9)
+
+    def test_reduce_complex(self):
+        assert_equal(np.fmax.reduce([1, 2j]), 1)
+        assert_equal(np.fmax.reduce([1+3j, 2j]), 1+3j)
+
+    def test_float_nans(self):
+        nan = np.nan
+        arg1 = np.array([0,   nan, nan])
+        arg2 = np.array([nan, 0,   nan])
+        out = np.array([0,   0,   nan])
+        assert_equal(np.fmax(arg1, arg2), out)
+
+    def test_complex_nans(self):
+        nan = np.nan
+        for cnan in [complex(nan, 0), complex(0, nan), complex(nan, nan)]:
+            arg1 = np.array([0, cnan, cnan], dtype=complex)
+            arg2 = np.array([cnan, 0, cnan], dtype=complex)
+            out = np.array([0,    0, nan], dtype=complex)
+            assert_equal(np.fmax(arg1, arg2), out)
+
+    def test_precision(self):
+        dtypes = [np.float16, np.float32, np.float64, np.longdouble]
+
+        for dt in dtypes:
+            dtmin = np.finfo(dt).min
+            dtmax = np.finfo(dt).max
+            d1 = dt(0.1)
+            d1_next = np.nextafter(d1, np.inf)
+
+            test_cases = [
+                # v1    v2          expected
+                (dtmin, -np.inf,    dtmin),
+                (dtmax, -np.inf,    dtmax),
+                (d1,    d1_next,    d1_next),
+                (dtmax, np.nan,     dtmax),
+            ]
+
+            for v1, v2, expected in test_cases:
+                assert_equal(np.fmax([v1], [v2]), [expected])
+                assert_equal(np.fmax.reduce([v1, v2]), expected)
+
+
+class TestFmin(_FilterInvalids):
+    def test_reduce(self):
+        dflt = np.typecodes['AllFloat']
+        dint = np.typecodes['AllInteger']
+        seq1 = np.arange(11)
+        seq2 = seq1[::-1]
+        func = np.fmin.reduce
+        for dt in dint:
+            tmp1 = seq1.astype(dt)
+            tmp2 = seq2.astype(dt)
+            assert_equal(func(tmp1), 0)
+            assert_equal(func(tmp2), 0)
+        for dt in dflt:
+            tmp1 = seq1.astype(dt)
+            tmp2 = seq2.astype(dt)
+            assert_equal(func(tmp1), 0)
+            assert_equal(func(tmp2), 0)
+            tmp1[::2] = np.nan
+            tmp2[::2] = np.nan
+            assert_equal(func(tmp1), 1)
+            assert_equal(func(tmp2), 1)
+
+    def test_reduce_complex(self):
+        assert_equal(np.fmin.reduce([1, 2j]), 2j)
+        assert_equal(np.fmin.reduce([1+3j, 2j]), 2j)
+
+    def test_float_nans(self):
+        nan = np.nan
+        arg1 = np.array([0,   nan, nan])
+        arg2 = np.array([nan, 0,   nan])
+        out = np.array([0,   0,   nan])
+        assert_equal(np.fmin(arg1, arg2), out)
+
+    def test_complex_nans(self):
+        nan = np.nan
+        for cnan in [complex(nan, 0), complex(0, nan), complex(nan, nan)]:
+            arg1 = np.array([0, cnan, cnan], dtype=complex)
+            arg2 = np.array([cnan, 0, cnan], dtype=complex)
+            out = np.array([0,    0, nan], dtype=complex)
+            assert_equal(np.fmin(arg1, arg2), out)
+
+    def test_precision(self):
+        dtypes = [np.float16, np.float32, np.float64, np.longdouble]
+
+        for dt in dtypes:
+            dtmin = np.finfo(dt).min
+            dtmax = np.finfo(dt).max
+            d1 = dt(0.1)
+            d1_next = np.nextafter(d1, np.inf)
+
+            test_cases = [
+                # v1    v2          expected
+                (dtmin, np.inf,     dtmin),
+                (dtmax, np.inf,     dtmax),
+                (d1,    d1_next,    d1),
+                (dtmin, np.nan,     dtmin),
+            ]
+
+            for v1, v2, expected in test_cases:
+                assert_equal(np.fmin([v1], [v2]), [expected])
+                assert_equal(np.fmin.reduce([v1, v2]), expected)
+
+
+class TestBool:
+    def test_exceptions(self):
+        a = np.ones(1, dtype=np.bool_)
+        assert_raises(TypeError, np.negative, a)
+        assert_raises(TypeError, np.positive, a)
+        assert_raises(TypeError, np.subtract, a, a)
+
+    def test_truth_table_logical(self):
+        # 2, 3 and 4 serves as true values
+        input1 = [0, 0, 3, 2]
+        input2 = [0, 4, 0, 2]
+
+        typecodes = (np.typecodes['AllFloat']
+                     + np.typecodes['AllInteger']
+                     + '?')     # boolean
+        for dtype in map(np.dtype, typecodes):
+            arg1 = np.asarray(input1, dtype=dtype)
+            arg2 = np.asarray(input2, dtype=dtype)
+
+            # OR
+            out = [False, True, True, True]
+            for func in (np.logical_or, np.maximum):
+                assert_equal(func(arg1, arg2).astype(bool), out)
+            # AND
+            out = [False, False, False, True]
+            for func in (np.logical_and, np.minimum):
+                assert_equal(func(arg1, arg2).astype(bool), out)
+            # XOR
+            out = [False, True, True, False]
+            for func in (np.logical_xor, np.not_equal):
+                assert_equal(func(arg1, arg2).astype(bool), out)
+
+    def test_truth_table_bitwise(self):
+        arg1 = [False, False, True, True]
+        arg2 = [False, True, False, True]
+
+        out = [False, True, True, True]
+        assert_equal(np.bitwise_or(arg1, arg2), out)
+
+        out = [False, False, False, True]
+        assert_equal(np.bitwise_and(arg1, arg2), out)
+
+        out = [False, True, True, False]
+        assert_equal(np.bitwise_xor(arg1, arg2), out)
+
+    def test_reduce(self):
+        none = np.array([0, 0, 0, 0], bool)
+        some = np.array([1, 0, 1, 1], bool)
+        every = np.array([1, 1, 1, 1], bool)
+        empty = np.array([], bool)
+
+        arrs = [none, some, every, empty]
+
+        for arr in arrs:
+            assert_equal(np.logical_and.reduce(arr), all(arr))
+
+        for arr in arrs:
+            assert_equal(np.logical_or.reduce(arr), any(arr))
+
+        for arr in arrs:
+            assert_equal(np.logical_xor.reduce(arr), arr.sum() % 2 == 1)
+
+
+class TestBitwiseUFuncs:
+
+    bitwise_types = [np.dtype(c) for c in '?' + 'bBhHiIlLqQ' + 'O']
+
+    def test_values(self):
+        for dt in self.bitwise_types:
+            zeros = np.array([0], dtype=dt)
+            ones = np.array([-1]).astype(dt)
+            msg = "dt = '%s'" % dt.char
+
+            assert_equal(np.bitwise_not(zeros), ones, err_msg=msg)
+            assert_equal(np.bitwise_not(ones), zeros, err_msg=msg)
+
+            assert_equal(np.bitwise_or(zeros, zeros), zeros, err_msg=msg)
+            assert_equal(np.bitwise_or(zeros, ones), ones, err_msg=msg)
+            assert_equal(np.bitwise_or(ones, zeros), ones, err_msg=msg)
+            assert_equal(np.bitwise_or(ones, ones), ones, err_msg=msg)
+
+            assert_equal(np.bitwise_xor(zeros, zeros), zeros, err_msg=msg)
+            assert_equal(np.bitwise_xor(zeros, ones), ones, err_msg=msg)
+            assert_equal(np.bitwise_xor(ones, zeros), ones, err_msg=msg)
+            assert_equal(np.bitwise_xor(ones, ones), zeros, err_msg=msg)
+
+            assert_equal(np.bitwise_and(zeros, zeros), zeros, err_msg=msg)
+            assert_equal(np.bitwise_and(zeros, ones), zeros, err_msg=msg)
+            assert_equal(np.bitwise_and(ones, zeros), zeros, err_msg=msg)
+            assert_equal(np.bitwise_and(ones, ones), ones, err_msg=msg)
+
+    def test_types(self):
+        for dt in self.bitwise_types:
+            zeros = np.array([0], dtype=dt)
+            ones = np.array([-1]).astype(dt)
+            msg = "dt = '%s'" % dt.char
+
+            assert_(np.bitwise_not(zeros).dtype == dt, msg)
+            assert_(np.bitwise_or(zeros, zeros).dtype == dt, msg)
+            assert_(np.bitwise_xor(zeros, zeros).dtype == dt, msg)
+            assert_(np.bitwise_and(zeros, zeros).dtype == dt, msg)
+
+    def test_identity(self):
+        assert_(np.bitwise_or.identity == 0, 'bitwise_or')
+        assert_(np.bitwise_xor.identity == 0, 'bitwise_xor')
+        assert_(np.bitwise_and.identity == -1, 'bitwise_and')
+
+    def test_reduction(self):
+        binary_funcs = (np.bitwise_or, np.bitwise_xor, np.bitwise_and)
+
+        for dt in self.bitwise_types:
+            zeros = np.array([0], dtype=dt)
+            ones = np.array([-1]).astype(dt)
+            for f in binary_funcs:
+                msg = "dt: '%s', f: '%s'" % (dt, f)
+                assert_equal(f.reduce(zeros), zeros, err_msg=msg)
+                assert_equal(f.reduce(ones), ones, err_msg=msg)
+
+        # Test empty reduction, no object dtype
+        for dt in self.bitwise_types[:-1]:
+            # No object array types
+            empty = np.array([], dtype=dt)
+            for f in binary_funcs:
+                msg = "dt: '%s', f: '%s'" % (dt, f)
+                tgt = np.array(f.identity).astype(dt)
+                res = f.reduce(empty)
+                assert_equal(res, tgt, err_msg=msg)
+                assert_(res.dtype == tgt.dtype, msg)
+
+        # Empty object arrays use the identity.  Note that the types may
+        # differ, the actual type used is determined by the assign_identity
+        # function and is not the same as the type returned by the identity
+        # method.
+        for f in binary_funcs:
+            msg = "dt: '%s'" % (f,)
+            empty = np.array([], dtype=object)
+            tgt = f.identity
+            res = f.reduce(empty)
+            assert_equal(res, tgt, err_msg=msg)
+
+        # Non-empty object arrays do not use the identity
+        for f in binary_funcs:
+            msg = "dt: '%s'" % (f,)
+            btype = np.array([True], dtype=object)
+            assert_(type(f.reduce(btype)) is bool, msg)
+
+
+class TestInt:
+    def test_logical_not(self):
+        x = np.ones(10, dtype=np.int16)
+        o = np.ones(10 * 2, dtype=bool)
+        tgt = o.copy()
+        tgt[::2] = False
+        os = o[::2]
+        assert_array_equal(np.logical_not(x, out=os), False)
+        assert_array_equal(o, tgt)
+
+
+class TestFloatingPoint:
+    def test_floating_point(self):
+        assert_equal(ncu.FLOATING_POINT_SUPPORT, 1)
+
+
+class TestDegrees:
+    def test_degrees(self):
+        assert_almost_equal(ncu.degrees(np.pi), 180.0)
+        assert_almost_equal(ncu.degrees(-0.5*np.pi), -90.0)
+
+
+class TestRadians:
+    def test_radians(self):
+        assert_almost_equal(ncu.radians(180.0), np.pi)
+        assert_almost_equal(ncu.radians(-90.0), -0.5*np.pi)
+
+
+class TestHeavside:
+    def test_heaviside(self):
+        x = np.array([[-30.0, -0.1, 0.0, 0.2], [7.5, np.nan, np.inf, -np.inf]])
+        expectedhalf = np.array([[0.0, 0.0, 0.5, 1.0], [1.0, np.nan, 1.0, 0.0]])
+        expected1 = expectedhalf.copy()
+        expected1[0, 2] = 1
+
+        h = ncu.heaviside(x, 0.5)
+        assert_equal(h, expectedhalf)
+
+        h = ncu.heaviside(x, 1.0)
+        assert_equal(h, expected1)
+
+        x = x.astype(np.float32)
+
+        h = ncu.heaviside(x, np.float32(0.5))
+        assert_equal(h, expectedhalf.astype(np.float32))
+
+        h = ncu.heaviside(x, np.float32(1.0))
+        assert_equal(h, expected1.astype(np.float32))
+
+
+class TestSign:
+    def test_sign(self):
+        a = np.array([np.inf, -np.inf, np.nan, 0.0, 3.0, -3.0])
+        out = np.zeros(a.shape)
+        tgt = np.array([1., -1., np.nan, 0.0, 1.0, -1.0])
+
+        with np.errstate(invalid='ignore'):
+            res = ncu.sign(a)
+            assert_equal(res, tgt)
+            res = ncu.sign(a, out)
+            assert_equal(res, tgt)
+            assert_equal(out, tgt)
+
+    def test_sign_dtype_object(self):
+        # In reference to github issue #6229
+
+        foo = np.array([-.1, 0, .1])
+        a = np.sign(foo.astype(object))
+        b = np.sign(foo)
+
+        assert_array_equal(a, b)
+
+    def test_sign_dtype_nan_object(self):
+        # In reference to github issue #6229
+        def test_nan():
+            foo = np.array([np.nan])
+            # FIXME: a not used
+            a = np.sign(foo.astype(object))
+
+        assert_raises(TypeError, test_nan)
+
+class TestMinMax:
+    def test_minmax_blocked(self):
+        # simd tests on max/min, test all alignments, slow but important
+        # for 2 * vz + 2 * (vs - 1) + 1 (unrolled once)
+        for dt, sz in [(np.float32, 15), (np.float64, 7)]:
+            for out, inp, msg in _gen_alignment_data(dtype=dt, type='unary',
+                                                     max_size=sz):
+                for i in range(inp.size):
+                    inp[:] = np.arange(inp.size, dtype=dt)
+                    inp[i] = np.nan
+                    emsg = lambda: '%r\n%s' % (inp, msg)
+                    with suppress_warnings() as sup:
+                        sup.filter(RuntimeWarning,
+                                   "invalid value encountered in reduce")
+                        assert_(np.isnan(inp.max()), msg=emsg)
+                        assert_(np.isnan(inp.min()), msg=emsg)
+
+                    inp[i] = 1e10
+                    assert_equal(inp.max(), 1e10, err_msg=msg)
+                    inp[i] = -1e10
+                    assert_equal(inp.min(), -1e10, err_msg=msg)
+
+    def test_lower_align(self):
+        # check data that is not aligned to element size
+        # i.e doubles are aligned to 4 bytes on i386
+        d = np.zeros(23 * 8, dtype=np.int8)[4:-4].view(np.float64)
+        assert_equal(d.max(), d[0])
+        assert_equal(d.min(), d[0])
+
+    def test_reduce_reorder(self):
+        # gh 10370, 11029 Some compilers reorder the call to npy_getfloatstatus
+        # and put it before the call to an intrisic function that causes
+        # invalid status to be set. Also make sure warnings are not emitted
+        for n in (2, 4, 8, 16, 32):
+            for dt in (np.float32, np.float16, np.complex64):
+                for r in np.diagflat(np.array([np.nan] * n, dtype=dt)):
+                    assert_equal(np.min(r), np.nan)
+
+    def test_minimize_no_warns(self):
+        a = np.minimum(np.nan, 1)
+        assert_equal(a, np.nan)
+
+
+class TestAbsoluteNegative:
+    def test_abs_neg_blocked(self):
+        # simd tests on abs, test all alignments for vz + 2 * (vs - 1) + 1
+        for dt, sz in [(np.float32, 11), (np.float64, 5)]:
+            for out, inp, msg in _gen_alignment_data(dtype=dt, type='unary',
+                                                     max_size=sz):
+                tgt = [ncu.absolute(i) for i in inp]
+                np.absolute(inp, out=out)
+                assert_equal(out, tgt, err_msg=msg)
+                assert_((out >= 0).all())
+
+                tgt = [-1*(i) for i in inp]
+                np.negative(inp, out=out)
+                assert_equal(out, tgt, err_msg=msg)
+
+                for v in [np.nan, -np.inf, np.inf]:
+                    for i in range(inp.size):
+                        d = np.arange(inp.size, dtype=dt)
+                        inp[:] = -d
+                        inp[i] = v
+                        d[i] = -v if v == -np.inf else v
+                        assert_array_equal(np.abs(inp), d, err_msg=msg)
+                        np.abs(inp, out=out)
+                        assert_array_equal(out, d, err_msg=msg)
+
+                        assert_array_equal(-inp, -1*inp, err_msg=msg)
+                        d = -1 * inp
+                        np.negative(inp, out=out)
+                        assert_array_equal(out, d, err_msg=msg)
+
+    def test_lower_align(self):
+        # check data that is not aligned to element size
+        # i.e doubles are aligned to 4 bytes on i386
+        d = np.zeros(23 * 8, dtype=np.int8)[4:-4].view(np.float64)
+        assert_equal(np.abs(d), d)
+        assert_equal(np.negative(d), -d)
+        np.negative(d, out=d)
+        np.negative(np.ones_like(d), out=d)
+        np.abs(d, out=d)
+        np.abs(np.ones_like(d), out=d)
+
+    @pytest.mark.parametrize("dtype", ['d', 'f', 'int32', 'int64'])
+    @pytest.mark.parametrize("big", [True, False])
+    def test_noncontiguous(self, dtype, big):
+        data = np.array([-1.0, 1.0, -0.0, 0.0, 2.2251e-308, -2.5, 2.5, -6,
+                            6, -2.2251e-308, -8, 10], dtype=dtype)
+        expect = np.array([1.0, -1.0, 0.0, -0.0, -2.2251e-308, 2.5, -2.5, 6,
+                            -6, 2.2251e-308, 8, -10], dtype=dtype)
+        if big:
+            data = np.repeat(data, 10)
+            expect = np.repeat(expect, 10)
+        out = np.ndarray(data.shape, dtype=dtype)
+        ncontig_in = data[1::2]
+        ncontig_out = out[1::2]
+        contig_in = np.array(ncontig_in)
+        # contig in, contig out
+        assert_array_equal(np.negative(contig_in), expect[1::2])
+        # contig in, ncontig out
+        assert_array_equal(np.negative(contig_in, out=ncontig_out),
+                                expect[1::2])
+        # ncontig in, contig out
+        assert_array_equal(np.negative(ncontig_in), expect[1::2])
+        # ncontig in, ncontig out
+        assert_array_equal(np.negative(ncontig_in, out=ncontig_out),
+                                expect[1::2])
+        # contig in, contig out, nd stride
+        data_split = np.array(np.array_split(data, 2))
+        expect_split = np.array(np.array_split(expect, 2))
+        assert_equal(np.negative(data_split), expect_split)
+
+
+class TestPositive:
+    def test_valid(self):
+        valid_dtypes = [int, float, complex, object]
+        for dtype in valid_dtypes:
+            x = np.arange(5, dtype=dtype)
+            result = np.positive(x)
+            assert_equal(x, result, err_msg=str(dtype))
+
+    def test_invalid(self):
+        with assert_raises(TypeError):
+            np.positive(True)
+        with assert_raises(TypeError):
+            np.positive(np.datetime64('2000-01-01'))
+        with assert_raises(TypeError):
+            np.positive(np.array(['foo'], dtype=str))
+        with assert_raises(TypeError):
+            np.positive(np.array(['bar'], dtype=object))
+
+
+class TestSpecialMethods:
+    def test_wrap(self):
+
+        class with_wrap:
+            def __array__(self):
+                return np.zeros(1)
+
+            def __array_wrap__(self, arr, context):
+                r = with_wrap()
+                r.arr = arr
+                r.context = context
+                return r
+
+        a = with_wrap()
+        x = ncu.minimum(a, a)
+        assert_equal(x.arr, np.zeros(1))
+        func, args, i = x.context
+        assert_(func is ncu.minimum)
+        assert_equal(len(args), 2)
+        assert_equal(args[0], a)
+        assert_equal(args[1], a)
+        assert_equal(i, 0)
+
+    def test_wrap_and_prepare_out(self):
+        # Calling convention for out should not affect how special methods are
+        # called
+
+        class StoreArrayPrepareWrap(np.ndarray):
+            _wrap_args = None
+            _prepare_args = None
+            def __new__(cls):
+                return np.zeros(()).view(cls)
+            def __array_wrap__(self, obj, context):
+                self._wrap_args = context[1]
+                return obj
+            def __array_prepare__(self, obj, context):
+                self._prepare_args = context[1]
+                return obj
+            @property
+            def args(self):
+                # We need to ensure these are fetched at the same time, before
+                # any other ufuncs are called by the assertions
+                return (self._prepare_args, self._wrap_args)
+            def __repr__(self):
+                return "a"  # for short test output
+
+        def do_test(f_call, f_expected):
+            a = StoreArrayPrepareWrap()
+            f_call(a)
+            p, w = a.args
+            expected = f_expected(a)
+            try:
+                assert_equal(p, expected)
+                assert_equal(w, expected)
+            except AssertionError as e:
+                # assert_equal produces truly useless error messages
+                raise AssertionError("\n".join([
+                    "Bad arguments passed in ufunc call",
+                    " expected:              {}".format(expected),
+                    " __array_prepare__ got: {}".format(p),
+                    " __array_wrap__ got:    {}".format(w)
+                ]))
+
+        # method not on the out argument
+        do_test(lambda a: np.add(a, 0),              lambda a: (a, 0))
+        do_test(lambda a: np.add(a, 0, None),        lambda a: (a, 0))
+        do_test(lambda a: np.add(a, 0, out=None),    lambda a: (a, 0))
+        do_test(lambda a: np.add(a, 0, out=(None,)), lambda a: (a, 0))
+
+        # method on the out argument
+        do_test(lambda a: np.add(0, 0, a),           lambda a: (0, 0, a))
+        do_test(lambda a: np.add(0, 0, out=a),       lambda a: (0, 0, a))
+        do_test(lambda a: np.add(0, 0, out=(a,)),    lambda a: (0, 0, a))
+
+        # Also check the where mask handling:
+        do_test(lambda a: np.add(a, 0, where=False), lambda a: (a, 0))
+        do_test(lambda a: np.add(0, 0, a, where=False), lambda a: (0, 0, a))
+
+    def test_wrap_with_iterable(self):
+        # test fix for bug #1026:
+
+        class with_wrap(np.ndarray):
+            __array_priority__ = 10
+
+            def __new__(cls):
+                return np.asarray(1).view(cls).copy()
+
+            def __array_wrap__(self, arr, context):
+                return arr.view(type(self))
+
+        a = with_wrap()
+        x = ncu.multiply(a, (1, 2, 3))
+        assert_(isinstance(x, with_wrap))
+        assert_array_equal(x, np.array((1, 2, 3)))
+
+    def test_priority_with_scalar(self):
+        # test fix for bug #826:
+
+        class A(np.ndarray):
+            __array_priority__ = 10
+
+            def __new__(cls):
+                return np.asarray(1.0, 'float64').view(cls).copy()
+
+        a = A()
+        x = np.float64(1)*a
+        assert_(isinstance(x, A))
+        assert_array_equal(x, np.array(1))
+
+    def test_old_wrap(self):
+
+        class with_wrap:
+            def __array__(self):
+                return np.zeros(1)
+
+            def __array_wrap__(self, arr):
+                r = with_wrap()
+                r.arr = arr
+                return r
+
+        a = with_wrap()
+        x = ncu.minimum(a, a)
+        assert_equal(x.arr, np.zeros(1))
+
+    def test_priority(self):
+
+        class A:
+            def __array__(self):
+                return np.zeros(1)
+
+            def __array_wrap__(self, arr, context):
+                r = type(self)()
+                r.arr = arr
+                r.context = context
+                return r
+
+        class B(A):
+            __array_priority__ = 20.
+
+        class C(A):
+            __array_priority__ = 40.
+
+        x = np.zeros(1)
+        a = A()
+        b = B()
+        c = C()
+        f = ncu.minimum
+        assert_(type(f(x, x)) is np.ndarray)
+        assert_(type(f(x, a)) is A)
+        assert_(type(f(x, b)) is B)
+        assert_(type(f(x, c)) is C)
+        assert_(type(f(a, x)) is A)
+        assert_(type(f(b, x)) is B)
+        assert_(type(f(c, x)) is C)
+
+        assert_(type(f(a, a)) is A)
+        assert_(type(f(a, b)) is B)
+        assert_(type(f(b, a)) is B)
+        assert_(type(f(b, b)) is B)
+        assert_(type(f(b, c)) is C)
+        assert_(type(f(c, b)) is C)
+        assert_(type(f(c, c)) is C)
+
+        assert_(type(ncu.exp(a) is A))
+        assert_(type(ncu.exp(b) is B))
+        assert_(type(ncu.exp(c) is C))
+
+    def test_failing_wrap(self):
+
+        class A:
+            def __array__(self):
+                return np.zeros(2)
+
+            def __array_wrap__(self, arr, context):
+                raise RuntimeError
+
+        a = A()
+        assert_raises(RuntimeError, ncu.maximum, a, a)
+        assert_raises(RuntimeError, ncu.maximum.reduce, a)
+
+    def test_failing_out_wrap(self):
+
+        singleton = np.array([1.0])
+
+        class Ok(np.ndarray):
+            def __array_wrap__(self, obj):
+                return singleton
+
+        class Bad(np.ndarray):
+            def __array_wrap__(self, obj):
+                raise RuntimeError
+
+        ok = np.empty(1).view(Ok)
+        bad = np.empty(1).view(Bad)
+        # double-free (segfault) of "ok" if "bad" raises an exception
+        for i in range(10):
+            assert_raises(RuntimeError, ncu.frexp, 1, ok, bad)
+
+    def test_none_wrap(self):
+        # Tests that issue #8507 is resolved. Previously, this would segfault
+
+        class A:
+            def __array__(self):
+                return np.zeros(1)
+
+            def __array_wrap__(self, arr, context=None):
+                return None
+
+        a = A()
+        assert_equal(ncu.maximum(a, a), None)
+
+    def test_default_prepare(self):
+
+        class with_wrap:
+            __array_priority__ = 10
+
+            def __array__(self):
+                return np.zeros(1)
+
+            def __array_wrap__(self, arr, context):
+                return arr
+
+        a = with_wrap()
+        x = ncu.minimum(a, a)
+        assert_equal(x, np.zeros(1))
+        assert_equal(type(x), np.ndarray)
+
+    @pytest.mark.parametrize("use_where", [True, False])
+    def test_prepare(self, use_where):
+
+        class with_prepare(np.ndarray):
+            __array_priority__ = 10
+
+            def __array_prepare__(self, arr, context):
+                # make sure we can return a new
+                return np.array(arr).view(type=with_prepare)
+
+        a = np.array(1).view(type=with_prepare)
+        if use_where:
+            x = np.add(a, a, where=np.array(True))
+        else:
+            x = np.add(a, a)
+        assert_equal(x, np.array(2))
+        assert_equal(type(x), with_prepare)
+
+    @pytest.mark.parametrize("use_where", [True, False])
+    def test_prepare_out(self, use_where):
+
+        class with_prepare(np.ndarray):
+            __array_priority__ = 10
+
+            def __array_prepare__(self, arr, context):
+                return np.array(arr).view(type=with_prepare)
+
+        a = np.array([1]).view(type=with_prepare)
+        if use_where:
+            x = np.add(a, a, a, where=[True])
+        else:
+            x = np.add(a, a, a)
+        # Returned array is new, because of the strange
+        # __array_prepare__ above
+        assert_(not np.shares_memory(x, a))
+        assert_equal(x, np.array([2]))
+        assert_equal(type(x), with_prepare)
+
+    def test_failing_prepare(self):
+
+        class A:
+            def __array__(self):
+                return np.zeros(1)
+
+            def __array_prepare__(self, arr, context=None):
+                raise RuntimeError
+
+        a = A()
+        assert_raises(RuntimeError, ncu.maximum, a, a)
+        assert_raises(RuntimeError, ncu.maximum, a, a, where=False)
+
+    def test_array_too_many_args(self):
+
+        class A:
+            def __array__(self, dtype, context):
+                return np.zeros(1)
+
+        a = A()
+        assert_raises_regex(TypeError, '2 required positional', np.sum, a)
+
+    def test_ufunc_override(self):
+        # check override works even with instance with high priority.
+        class A:
+            def __array_ufunc__(self, func, method, *inputs, **kwargs):
+                return self, func, method, inputs, kwargs
+
+        class MyNDArray(np.ndarray):
+            __array_priority__ = 100
+
+        a = A()
+        b = np.array([1]).view(MyNDArray)
+        res0 = np.multiply(a, b)
+        res1 = np.multiply(b, b, out=a)
+
+        # self
+        assert_equal(res0[0], a)
+        assert_equal(res1[0], a)
+        assert_equal(res0[1], np.multiply)
+        assert_equal(res1[1], np.multiply)
+        assert_equal(res0[2], '__call__')
+        assert_equal(res1[2], '__call__')
+        assert_equal(res0[3], (a, b))
+        assert_equal(res1[3], (b, b))
+        assert_equal(res0[4], {})
+        assert_equal(res1[4], {'out': (a,)})
+
+    def test_ufunc_override_mro(self):
+
+        # Some multi arg functions for testing.
+        def tres_mul(a, b, c):
+            return a * b * c
+
+        def quatro_mul(a, b, c, d):
+            return a * b * c * d
+
+        # Make these into ufuncs.
+        three_mul_ufunc = np.frompyfunc(tres_mul, 3, 1)
+        four_mul_ufunc = np.frompyfunc(quatro_mul, 4, 1)
+
+        class A:
+            def __array_ufunc__(self, func, method, *inputs, **kwargs):
+                return "A"
+
+        class ASub(A):
+            def __array_ufunc__(self, func, method, *inputs, **kwargs):
+                return "ASub"
+
+        class B:
+            def __array_ufunc__(self, func, method, *inputs, **kwargs):
+                return "B"
+
+        class C:
+            def __init__(self):
+                self.count = 0
+
+            def __array_ufunc__(self, func, method, *inputs, **kwargs):
+                self.count += 1
+                return NotImplemented
+
+        class CSub(C):
+            def __array_ufunc__(self, func, method, *inputs, **kwargs):
+                self.count += 1
+                return NotImplemented
+
+        a = A()
+        a_sub = ASub()
+        b = B()
+        c = C()
+
+        # Standard
+        res = np.multiply(a, a_sub)
+        assert_equal(res, "ASub")
+        res = np.multiply(a_sub, b)
+        assert_equal(res, "ASub")
+
+        # With 1 NotImplemented
+        res = np.multiply(c, a)
+        assert_equal(res, "A")
+        assert_equal(c.count, 1)
+        # Check our counter works, so we can trust tests below.
+        res = np.multiply(c, a)
+        assert_equal(c.count, 2)
+
+        # Both NotImplemented.
+        c = C()
+        c_sub = CSub()
+        assert_raises(TypeError, np.multiply, c, c_sub)
+        assert_equal(c.count, 1)
+        assert_equal(c_sub.count, 1)
+        c.count = c_sub.count = 0
+        assert_raises(TypeError, np.multiply, c_sub, c)
+        assert_equal(c.count, 1)
+        assert_equal(c_sub.count, 1)
+        c.count = 0
+        assert_raises(TypeError, np.multiply, c, c)
+        assert_equal(c.count, 1)
+        c.count = 0
+        assert_raises(TypeError, np.multiply, 2, c)
+        assert_equal(c.count, 1)
+
+        # Ternary testing.
+        assert_equal(three_mul_ufunc(a, 1, 2), "A")
+        assert_equal(three_mul_ufunc(1, a, 2), "A")
+        assert_equal(three_mul_ufunc(1, 2, a), "A")
+
+        assert_equal(three_mul_ufunc(a, a, 6), "A")
+        assert_equal(three_mul_ufunc(a, 2, a), "A")
+        assert_equal(three_mul_ufunc(a, 2, b), "A")
+        assert_equal(three_mul_ufunc(a, 2, a_sub), "ASub")
+        assert_equal(three_mul_ufunc(a, a_sub, 3), "ASub")
+        c.count = 0
+        assert_equal(three_mul_ufunc(c, a_sub, 3), "ASub")
+        assert_equal(c.count, 1)
+        c.count = 0
+        assert_equal(three_mul_ufunc(1, a_sub, c), "ASub")
+        assert_equal(c.count, 0)
+
+        c.count = 0
+        assert_equal(three_mul_ufunc(a, b, c), "A")
+        assert_equal(c.count, 0)
+        c_sub.count = 0
+        assert_equal(three_mul_ufunc(a, b, c_sub), "A")
+        assert_equal(c_sub.count, 0)
+        assert_equal(three_mul_ufunc(1, 2, b), "B")
+
+        assert_raises(TypeError, three_mul_ufunc, 1, 2, c)
+        assert_raises(TypeError, three_mul_ufunc, c_sub, 2, c)
+        assert_raises(TypeError, three_mul_ufunc, c_sub, 2, 3)
+
+        # Quaternary testing.
+        assert_equal(four_mul_ufunc(a, 1, 2, 3), "A")
+        assert_equal(four_mul_ufunc(1, a, 2, 3), "A")
+        assert_equal(four_mul_ufunc(1, 1, a, 3), "A")
+        assert_equal(four_mul_ufunc(1, 1, 2, a), "A")
+
+        assert_equal(four_mul_ufunc(a, b, 2, 3), "A")
+        assert_equal(four_mul_ufunc(1, a, 2, b), "A")
+        assert_equal(four_mul_ufunc(b, 1, a, 3), "B")
+        assert_equal(four_mul_ufunc(a_sub, 1, 2, a), "ASub")
+        assert_equal(four_mul_ufunc(a, 1, 2, a_sub), "ASub")
+
+        c = C()
+        c_sub = CSub()
+        assert_raises(TypeError, four_mul_ufunc, 1, 2, 3, c)
+        assert_equal(c.count, 1)
+        c.count = 0
+        assert_raises(TypeError, four_mul_ufunc, 1, 2, c_sub, c)
+        assert_equal(c_sub.count, 1)
+        assert_equal(c.count, 1)
+        c2 = C()
+        c.count = c_sub.count = 0
+        assert_raises(TypeError, four_mul_ufunc, 1, c, c_sub, c2)
+        assert_equal(c_sub.count, 1)
+        assert_equal(c.count, 1)
+        assert_equal(c2.count, 0)
+        c.count = c2.count = c_sub.count = 0
+        assert_raises(TypeError, four_mul_ufunc, c2, c, c_sub, c)
+        assert_equal(c_sub.count, 1)
+        assert_equal(c.count, 0)
+        assert_equal(c2.count, 1)
+
+    def test_ufunc_override_methods(self):
+
+        class A:
+            def __array_ufunc__(self, ufunc, method, *inputs, **kwargs):
+                return self, ufunc, method, inputs, kwargs
+
+        # __call__
+        a = A()
+        with assert_raises(TypeError):
+            np.multiply.__call__(1, a, foo='bar', answer=42)
+        res = np.multiply.__call__(1, a, subok='bar', where=42)
+        assert_equal(res[0], a)
+        assert_equal(res[1], np.multiply)
+        assert_equal(res[2], '__call__')
+        assert_equal(res[3], (1, a))
+        assert_equal(res[4], {'subok': 'bar', 'where': 42})
+
+        # __call__, wrong args
+        assert_raises(TypeError, np.multiply, a)
+        assert_raises(TypeError, np.multiply, a, a, a, a)
+        assert_raises(TypeError, np.multiply, a, a, sig='a', signature='a')
+        assert_raises(TypeError, ncu_tests.inner1d, a, a, axis=0, axes=[0, 0])
+
+        # reduce, positional args
+        res = np.multiply.reduce(a, 'axis0', 'dtype0', 'out0', 'keep0')
+        assert_equal(res[0], a)
+        assert_equal(res[1], np.multiply)
+        assert_equal(res[2], 'reduce')
+        assert_equal(res[3], (a,))
+        assert_equal(res[4], {'dtype':'dtype0',
+                              'out': ('out0',),
+                              'keepdims': 'keep0',
+                              'axis': 'axis0'})
+
+        # reduce, kwargs
+        res = np.multiply.reduce(a, axis='axis0', dtype='dtype0', out='out0',
+                                 keepdims='keep0', initial='init0',
+                                 where='where0')
+        assert_equal(res[0], a)
+        assert_equal(res[1], np.multiply)
+        assert_equal(res[2], 'reduce')
+        assert_equal(res[3], (a,))
+        assert_equal(res[4], {'dtype':'dtype0',
+                              'out': ('out0',),
+                              'keepdims': 'keep0',
+                              'axis': 'axis0',
+                              'initial': 'init0',
+                              'where': 'where0'})
+
+        # reduce, output equal to None removed, but not other explicit ones,
+        # even if they are at their default value.
+        res = np.multiply.reduce(a, 0, None, None, False)
+        assert_equal(res[4], {'axis': 0, 'dtype': None, 'keepdims': False})
+        res = np.multiply.reduce(a, out=None, axis=0, keepdims=True)
+        assert_equal(res[4], {'axis': 0, 'keepdims': True})
+        res = np.multiply.reduce(a, None, out=(None,), dtype=None)
+        assert_equal(res[4], {'axis': None, 'dtype': None})
+        res = np.multiply.reduce(a, 0, None, None, False, 2, True)
+        assert_equal(res[4], {'axis': 0, 'dtype': None, 'keepdims': False,
+                              'initial': 2, 'where': True})
+        # np._NoValue ignored for initial
+        res = np.multiply.reduce(a, 0, None, None, False,
+                                 np._NoValue, True)
+        assert_equal(res[4], {'axis': 0, 'dtype': None, 'keepdims': False,
+                              'where': True})
+        # None kept for initial, True for where.
+        res = np.multiply.reduce(a, 0, None, None, False, None, True)
+        assert_equal(res[4], {'axis': 0, 'dtype': None, 'keepdims': False,
+                              'initial': None, 'where': True})
+
+        # reduce, wrong args
+        assert_raises(ValueError, np.multiply.reduce, a, out=())
+        assert_raises(ValueError, np.multiply.reduce, a, out=('out0', 'out1'))
+        assert_raises(TypeError, np.multiply.reduce, a, 'axis0', axis='axis0')
+
+        # accumulate, pos args
+        res = np.multiply.accumulate(a, 'axis0', 'dtype0', 'out0')
+        assert_equal(res[0], a)
+        assert_equal(res[1], np.multiply)
+        assert_equal(res[2], 'accumulate')
+        assert_equal(res[3], (a,))
+        assert_equal(res[4], {'dtype':'dtype0',
+                              'out': ('out0',),
+                              'axis': 'axis0'})
+
+        # accumulate, kwargs
+        res = np.multiply.accumulate(a, axis='axis0', dtype='dtype0',
+                                     out='out0')
+        assert_equal(res[0], a)
+        assert_equal(res[1], np.multiply)
+        assert_equal(res[2], 'accumulate')
+        assert_equal(res[3], (a,))
+        assert_equal(res[4], {'dtype':'dtype0',
+                              'out': ('out0',),
+                              'axis': 'axis0'})
+
+        # accumulate, output equal to None removed.
+        res = np.multiply.accumulate(a, 0, None, None)
+        assert_equal(res[4], {'axis': 0, 'dtype': None})
+        res = np.multiply.accumulate(a, out=None, axis=0, dtype='dtype1')
+        assert_equal(res[4], {'axis': 0, 'dtype': 'dtype1'})
+        res = np.multiply.accumulate(a, None, out=(None,), dtype=None)
+        assert_equal(res[4], {'axis': None, 'dtype': None})
+
+        # accumulate, wrong args
+        assert_raises(ValueError, np.multiply.accumulate, a, out=())
+        assert_raises(ValueError, np.multiply.accumulate, a,
+                      out=('out0', 'out1'))
+        assert_raises(TypeError, np.multiply.accumulate, a,
+                      'axis0', axis='axis0')
+
+        # reduceat, pos args
+        res = np.multiply.reduceat(a, [4, 2], 'axis0', 'dtype0', 'out0')
+        assert_equal(res[0], a)
+        assert_equal(res[1], np.multiply)
+        assert_equal(res[2], 'reduceat')
+        assert_equal(res[3], (a, [4, 2]))
+        assert_equal(res[4], {'dtype':'dtype0',
+                              'out': ('out0',),
+                              'axis': 'axis0'})
+
+        # reduceat, kwargs
+        res = np.multiply.reduceat(a, [4, 2], axis='axis0', dtype='dtype0',
+                                   out='out0')
+        assert_equal(res[0], a)
+        assert_equal(res[1], np.multiply)
+        assert_equal(res[2], 'reduceat')
+        assert_equal(res[3], (a, [4, 2]))
+        assert_equal(res[4], {'dtype':'dtype0',
+                              'out': ('out0',),
+                              'axis': 'axis0'})
+
+        # reduceat, output equal to None removed.
+        res = np.multiply.reduceat(a, [4, 2], 0, None, None)
+        assert_equal(res[4], {'axis': 0, 'dtype': None})
+        res = np.multiply.reduceat(a, [4, 2], axis=None, out=None, dtype='dt')
+        assert_equal(res[4], {'axis': None, 'dtype': 'dt'})
+        res = np.multiply.reduceat(a, [4, 2], None, None, out=(None,))
+        assert_equal(res[4], {'axis': None, 'dtype': None})
+
+        # reduceat, wrong args
+        assert_raises(ValueError, np.multiply.reduce, a, [4, 2], out=())
+        assert_raises(ValueError, np.multiply.reduce, a, [4, 2],
+                      out=('out0', 'out1'))
+        assert_raises(TypeError, np.multiply.reduce, a, [4, 2],
+                      'axis0', axis='axis0')
+
+        # outer
+        res = np.multiply.outer(a, 42)
+        assert_equal(res[0], a)
+        assert_equal(res[1], np.multiply)
+        assert_equal(res[2], 'outer')
+        assert_equal(res[3], (a, 42))
+        assert_equal(res[4], {})
+
+        # outer, wrong args
+        assert_raises(TypeError, np.multiply.outer, a)
+        assert_raises(TypeError, np.multiply.outer, a, a, a, a)
+        assert_raises(TypeError, np.multiply.outer, a, a, sig='a', signature='a')
+
+        # at
+        res = np.multiply.at(a, [4, 2], 'b0')
+        assert_equal(res[0], a)
+        assert_equal(res[1], np.multiply)
+        assert_equal(res[2], 'at')
+        assert_equal(res[3], (a, [4, 2], 'b0'))
+
+        # at, wrong args
+        assert_raises(TypeError, np.multiply.at, a)
+        assert_raises(TypeError, np.multiply.at, a, a, a, a)
+
+    def test_ufunc_override_out(self):
+
+        class A:
+            def __array_ufunc__(self, ufunc, method, *inputs, **kwargs):
+                return kwargs
+
+        class B:
+            def __array_ufunc__(self, ufunc, method, *inputs, **kwargs):
+                return kwargs
+
+        a = A()
+        b = B()
+        res0 = np.multiply(a, b, 'out_arg')
+        res1 = np.multiply(a, b, out='out_arg')
+        res2 = np.multiply(2, b, 'out_arg')
+        res3 = np.multiply(3, b, out='out_arg')
+        res4 = np.multiply(a, 4, 'out_arg')
+        res5 = np.multiply(a, 5, out='out_arg')
+
+        assert_equal(res0['out'][0], 'out_arg')
+        assert_equal(res1['out'][0], 'out_arg')
+        assert_equal(res2['out'][0], 'out_arg')
+        assert_equal(res3['out'][0], 'out_arg')
+        assert_equal(res4['out'][0], 'out_arg')
+        assert_equal(res5['out'][0], 'out_arg')
+
+        # ufuncs with multiple output modf and frexp.
+        res6 = np.modf(a, 'out0', 'out1')
+        res7 = np.frexp(a, 'out0', 'out1')
+        assert_equal(res6['out'][0], 'out0')
+        assert_equal(res6['out'][1], 'out1')
+        assert_equal(res7['out'][0], 'out0')
+        assert_equal(res7['out'][1], 'out1')
+
+        # While we're at it, check that default output is never passed on.
+        assert_(np.sin(a, None) == {})
+        assert_(np.sin(a, out=None) == {})
+        assert_(np.sin(a, out=(None,)) == {})
+        assert_(np.modf(a, None) == {})
+        assert_(np.modf(a, None, None) == {})
+        assert_(np.modf(a, out=(None, None)) == {})
+        with assert_raises(TypeError):
+            # Out argument must be tuple, since there are multiple outputs.
+            np.modf(a, out=None)
+
+        # don't give positional and output argument, or too many arguments.
+        # wrong number of arguments in the tuple is an error too.
+        assert_raises(TypeError, np.multiply, a, b, 'one', out='two')
+        assert_raises(TypeError, np.multiply, a, b, 'one', 'two')
+        assert_raises(ValueError, np.multiply, a, b, out=('one', 'two'))
+        assert_raises(TypeError, np.multiply, a, out=())
+        assert_raises(TypeError, np.modf, a, 'one', out=('two', 'three'))
+        assert_raises(TypeError, np.modf, a, 'one', 'two', 'three')
+        assert_raises(ValueError, np.modf, a, out=('one', 'two', 'three'))
+        assert_raises(ValueError, np.modf, a, out=('one',))
+
+    def test_ufunc_override_where(self):
+
+        class OverriddenArrayOld(np.ndarray):
+
+            def _unwrap(self, objs):
+                cls = type(self)
+                result = []
+                for obj in objs:
+                    if isinstance(obj, cls):
+                        obj = np.array(obj)
+                    elif type(obj) != np.ndarray:
+                        return NotImplemented
+                    result.append(obj)
+                return result
+
+            def __array_ufunc__(self, ufunc, method, *inputs, **kwargs):
+
+                inputs = self._unwrap(inputs)
+                if inputs is NotImplemented:
+                    return NotImplemented
+
+                kwargs = kwargs.copy()
+                if "out" in kwargs:
+                    kwargs["out"] = self._unwrap(kwargs["out"])
+                    if kwargs["out"] is NotImplemented:
+                        return NotImplemented
+
+                r = super().__array_ufunc__(ufunc, method, *inputs, **kwargs)
+                if r is not NotImplemented:
+                    r = r.view(type(self))
+
+                return r
+
+        class OverriddenArrayNew(OverriddenArrayOld):
+            def __array_ufunc__(self, ufunc, method, *inputs, **kwargs):
+
+                kwargs = kwargs.copy()
+                if "where" in kwargs:
+                    kwargs["where"] = self._unwrap((kwargs["where"], ))
+                    if kwargs["where"] is NotImplemented:
+                        return NotImplemented
+                    else:
+                        kwargs["where"] = kwargs["where"][0]
+
+                r = super().__array_ufunc__(ufunc, method, *inputs, **kwargs)
+                if r is not NotImplemented:
+                    r = r.view(type(self))
+
+                return r
+
+        ufunc = np.negative
+
+        array = np.array([1, 2, 3])
+        where = np.array([True, False, True])
+        expected = ufunc(array, where=where)
+
+        with pytest.raises(TypeError):
+            ufunc(array, where=where.view(OverriddenArrayOld))
+
+        result_1 = ufunc(
+            array,
+            where=where.view(OverriddenArrayNew)
+        )
+        assert isinstance(result_1, OverriddenArrayNew)
+        assert np.all(np.array(result_1) == expected, where=where)
+
+        result_2 = ufunc(
+            array.view(OverriddenArrayNew),
+            where=where.view(OverriddenArrayNew)
+        )
+        assert isinstance(result_2, OverriddenArrayNew)
+        assert np.all(np.array(result_2) == expected, where=where)
+
+    def test_ufunc_override_exception(self):
+
+        class A:
+            def __array_ufunc__(self, *a, **kwargs):
+                raise ValueError("oops")
+
+        a = A()
+        assert_raises(ValueError, np.negative, 1, out=a)
+        assert_raises(ValueError, np.negative, a)
+        assert_raises(ValueError, np.divide, 1., a)
+
+    def test_ufunc_override_not_implemented(self):
+
+        class A:
+            def __array_ufunc__(self, *args, **kwargs):
+                return NotImplemented
+
+        msg = ("operand type(s) all returned NotImplemented from "
+               "__array_ufunc__(<ufunc 'negative'>, '__call__', <*>): 'A'")
+        with assert_raises_regex(TypeError, fnmatch.translate(msg)):
+            np.negative(A())
+
+        msg = ("operand type(s) all returned NotImplemented from "
+               "__array_ufunc__(<ufunc 'add'>, '__call__', <*>, <object *>, "
+               "out=(1,)): 'A', 'object', 'int'")
+        with assert_raises_regex(TypeError, fnmatch.translate(msg)):
+            np.add(A(), object(), out=1)
+
+    def test_ufunc_override_disabled(self):
+
+        class OptOut:
+            __array_ufunc__ = None
+
+        opt_out = OptOut()
+
+        # ufuncs always raise
+        msg = "operand 'OptOut' does not support ufuncs"
+        with assert_raises_regex(TypeError, msg):
+            np.add(opt_out, 1)
+        with assert_raises_regex(TypeError, msg):
+            np.add(1, opt_out)
+        with assert_raises_regex(TypeError, msg):
+            np.negative(opt_out)
+
+        # opt-outs still hold even when other arguments have pathological
+        # __array_ufunc__ implementations
+
+        class GreedyArray:
+            def __array_ufunc__(self, *args, **kwargs):
+                return self
+
+        greedy = GreedyArray()
+        assert_(np.negative(greedy) is greedy)
+        with assert_raises_regex(TypeError, msg):
+            np.add(greedy, opt_out)
+        with assert_raises_regex(TypeError, msg):
+            np.add(greedy, 1, out=opt_out)
+
+    def test_gufunc_override(self):
+        # gufunc are just ufunc instances, but follow a different path,
+        # so check __array_ufunc__ overrides them properly.
+        class A:
+            def __array_ufunc__(self, ufunc, method, *inputs, **kwargs):
+                return self, ufunc, method, inputs, kwargs
+
+        inner1d = ncu_tests.inner1d
+        a = A()
+        res = inner1d(a, a)
+        assert_equal(res[0], a)
+        assert_equal(res[1], inner1d)
+        assert_equal(res[2], '__call__')
+        assert_equal(res[3], (a, a))
+        assert_equal(res[4], {})
+
+        res = inner1d(1, 1, out=a)
+        assert_equal(res[0], a)
+        assert_equal(res[1], inner1d)
+        assert_equal(res[2], '__call__')
+        assert_equal(res[3], (1, 1))
+        assert_equal(res[4], {'out': (a,)})
+
+        # wrong number of arguments in the tuple is an error too.
+        assert_raises(TypeError, inner1d, a, out='two')
+        assert_raises(TypeError, inner1d, a, a, 'one', out='two')
+        assert_raises(TypeError, inner1d, a, a, 'one', 'two')
+        assert_raises(ValueError, inner1d, a, a, out=('one', 'two'))
+        assert_raises(ValueError, inner1d, a, a, out=())
+
+    def test_ufunc_override_with_super(self):
+        # NOTE: this class is used in doc/source/user/basics.subclassing.rst
+        # if you make any changes here, do update it there too.
+        class A(np.ndarray):
+            def __array_ufunc__(self, ufunc, method, *inputs, out=None, **kwargs):
+                args = []
+                in_no = []
+                for i, input_ in enumerate(inputs):
+                    if isinstance(input_, A):
+                        in_no.append(i)
+                        args.append(input_.view(np.ndarray))
+                    else:
+                        args.append(input_)
+
+                outputs = out
+                out_no = []
+                if outputs:
+                    out_args = []
+                    for j, output in enumerate(outputs):
+                        if isinstance(output, A):
+                            out_no.append(j)
+                            out_args.append(output.view(np.ndarray))
+                        else:
+                            out_args.append(output)
+                    kwargs['out'] = tuple(out_args)
+                else:
+                    outputs = (None,) * ufunc.nout
+
+                info = {}
+                if in_no:
+                    info['inputs'] = in_no
+                if out_no:
+                    info['outputs'] = out_no
+
+                results = super().__array_ufunc__(ufunc, method,
+                                                  *args, **kwargs)
+                if results is NotImplemented:
+                    return NotImplemented
+
+                if method == 'at':
+                    if isinstance(inputs[0], A):
+                        inputs[0].info = info
+                    return
+
+                if ufunc.nout == 1:
+                    results = (results,)
+
+                results = tuple((np.asarray(result).view(A)
+                                 if output is None else output)
+                                for result, output in zip(results, outputs))
+                if results and isinstance(results[0], A):
+                    results[0].info = info
+
+                return results[0] if len(results) == 1 else results
+
+        class B:
+            def __array_ufunc__(self, ufunc, method, *inputs, **kwargs):
+                if any(isinstance(input_, A) for input_ in inputs):
+                    return "A!"
+                else:
+                    return NotImplemented
+
+        d = np.arange(5.)
+        # 1 input, 1 output
+        a = np.arange(5.).view(A)
+        b = np.sin(a)
+        check = np.sin(d)
+        assert_(np.all(check == b))
+        assert_equal(b.info, {'inputs': [0]})
+        b = np.sin(d, out=(a,))
+        assert_(np.all(check == b))
+        assert_equal(b.info, {'outputs': [0]})
+        assert_(b is a)
+        a = np.arange(5.).view(A)
+        b = np.sin(a, out=a)
+        assert_(np.all(check == b))
+        assert_equal(b.info, {'inputs': [0], 'outputs': [0]})
+
+        # 1 input, 2 outputs
+        a = np.arange(5.).view(A)
+        b1, b2 = np.modf(a)
+        assert_equal(b1.info, {'inputs': [0]})
+        b1, b2 = np.modf(d, out=(None, a))
+        assert_(b2 is a)
+        assert_equal(b1.info, {'outputs': [1]})
+        a = np.arange(5.).view(A)
+        b = np.arange(5.).view(A)
+        c1, c2 = np.modf(a, out=(a, b))
+        assert_(c1 is a)
+        assert_(c2 is b)
+        assert_equal(c1.info, {'inputs': [0], 'outputs': [0, 1]})
+
+        # 2 input, 1 output
+        a = np.arange(5.).view(A)
+        b = np.arange(5.).view(A)
+        c = np.add(a, b, out=a)
+        assert_(c is a)
+        assert_equal(c.info, {'inputs': [0, 1], 'outputs': [0]})
+        # some tests with a non-ndarray subclass
+        a = np.arange(5.)
+        b = B()
+        assert_(a.__array_ufunc__(np.add, '__call__', a, b) is NotImplemented)
+        assert_(b.__array_ufunc__(np.add, '__call__', a, b) is NotImplemented)
+        assert_raises(TypeError, np.add, a, b)
+        a = a.view(A)
+        assert_(a.__array_ufunc__(np.add, '__call__', a, b) is NotImplemented)
+        assert_(b.__array_ufunc__(np.add, '__call__', a, b) == "A!")
+        assert_(np.add(a, b) == "A!")
+        # regression check for gh-9102 -- tests ufunc.reduce implicitly.
+        d = np.array([[1, 2, 3], [1, 2, 3]])
+        a = d.view(A)
+        c = a.any()
+        check = d.any()
+        assert_equal(c, check)
+        assert_(c.info, {'inputs': [0]})
+        c = a.max()
+        check = d.max()
+        assert_equal(c, check)
+        assert_(c.info, {'inputs': [0]})
+        b = np.array(0).view(A)
+        c = a.max(out=b)
+        assert_equal(c, check)
+        assert_(c is b)
+        assert_(c.info, {'inputs': [0], 'outputs': [0]})
+        check = a.max(axis=0)
+        b = np.zeros_like(check).view(A)
+        c = a.max(axis=0, out=b)
+        assert_equal(c, check)
+        assert_(c is b)
+        assert_(c.info, {'inputs': [0], 'outputs': [0]})
+        # simple explicit tests of reduce, accumulate, reduceat
+        check = np.add.reduce(d, axis=1)
+        c = np.add.reduce(a, axis=1)
+        assert_equal(c, check)
+        assert_(c.info, {'inputs': [0]})
+        b = np.zeros_like(c)
+        c = np.add.reduce(a, 1, None, b)
+        assert_equal(c, check)
+        assert_(c is b)
+        assert_(c.info, {'inputs': [0], 'outputs': [0]})
+        check = np.add.accumulate(d, axis=0)
+        c = np.add.accumulate(a, axis=0)
+        assert_equal(c, check)
+        assert_(c.info, {'inputs': [0]})
+        b = np.zeros_like(c)
+        c = np.add.accumulate(a, 0, None, b)
+        assert_equal(c, check)
+        assert_(c is b)
+        assert_(c.info, {'inputs': [0], 'outputs': [0]})
+        indices = [0, 2, 1]
+        check = np.add.reduceat(d, indices, axis=1)
+        c = np.add.reduceat(a, indices, axis=1)
+        assert_equal(c, check)
+        assert_(c.info, {'inputs': [0]})
+        b = np.zeros_like(c)
+        c = np.add.reduceat(a, indices, 1, None, b)
+        assert_equal(c, check)
+        assert_(c is b)
+        assert_(c.info, {'inputs': [0], 'outputs': [0]})
+        # and a few tests for at
+        d = np.array([[1, 2, 3], [1, 2, 3]])
+        check = d.copy()
+        a = d.copy().view(A)
+        np.add.at(check, ([0, 1], [0, 2]), 1.)
+        np.add.at(a, ([0, 1], [0, 2]), 1.)
+        assert_equal(a, check)
+        assert_(a.info, {'inputs': [0]})
+        b = np.array(1.).view(A)
+        a = d.copy().view(A)
+        np.add.at(a, ([0, 1], [0, 2]), b)
+        assert_equal(a, check)
+        assert_(a.info, {'inputs': [0, 2]})
+
+    def test_array_ufunc_direct_call(self):
+        # This is mainly a regression test for gh-24023 (shouldn't segfault)
+        a = np.array(1)
+        with pytest.raises(TypeError):
+            a.__array_ufunc__()
+
+        # No kwargs means kwargs may be NULL on the C-level
+        with pytest.raises(TypeError):
+            a.__array_ufunc__(1, 2)
+
+        # And the same with a valid call:
+        res = a.__array_ufunc__(np.add, "__call__", a, a)
+        assert_array_equal(res, a + a)
+
+class TestChoose:
+    def test_mixed(self):
+        c = np.array([True, True])
+        a = np.array([True, True])
+        assert_equal(np.choose(c, (a, 1)), np.array([1, 1]))
+
+
+class TestRationalFunctions:
+    def test_lcm(self):
+        self._test_lcm_inner(np.int16)
+        self._test_lcm_inner(np.uint16)
+
+    def test_lcm_object(self):
+        self._test_lcm_inner(np.object_)
+
+    def test_gcd(self):
+        self._test_gcd_inner(np.int16)
+        self._test_lcm_inner(np.uint16)
+
+    def test_gcd_object(self):
+        self._test_gcd_inner(np.object_)
+
+    def _test_lcm_inner(self, dtype):
+        # basic use
+        a = np.array([12, 120], dtype=dtype)
+        b = np.array([20, 200], dtype=dtype)
+        assert_equal(np.lcm(a, b), [60, 600])
+
+        if not issubclass(dtype, np.unsignedinteger):
+            # negatives are ignored
+            a = np.array([12, -12,  12, -12], dtype=dtype)
+            b = np.array([20,  20, -20, -20], dtype=dtype)
+            assert_equal(np.lcm(a, b), [60]*4)
+
+        # reduce
+        a = np.array([3, 12, 20], dtype=dtype)
+        assert_equal(np.lcm.reduce([3, 12, 20]), 60)
+
+        # broadcasting, and a test including 0
+        a = np.arange(6).astype(dtype)
+        b = 20
+        assert_equal(np.lcm(a, b), [0, 20, 20, 60, 20, 20])
+
+    def _test_gcd_inner(self, dtype):
+        # basic use
+        a = np.array([12, 120], dtype=dtype)
+        b = np.array([20, 200], dtype=dtype)
+        assert_equal(np.gcd(a, b), [4, 40])
+
+        if not issubclass(dtype, np.unsignedinteger):
+            # negatives are ignored
+            a = np.array([12, -12,  12, -12], dtype=dtype)
+            b = np.array([20,  20, -20, -20], dtype=dtype)
+            assert_equal(np.gcd(a, b), [4]*4)
+
+        # reduce
+        a = np.array([15, 25, 35], dtype=dtype)
+        assert_equal(np.gcd.reduce(a), 5)
+
+        # broadcasting, and a test including 0
+        a = np.arange(6).astype(dtype)
+        b = 20
+        assert_equal(np.gcd(a, b), [20,  1,  2,  1,  4,  5])
+
+    def test_lcm_overflow(self):
+        # verify that we don't overflow when a*b does overflow
+        big = np.int32(np.iinfo(np.int32).max // 11)
+        a = 2*big
+        b = 5*big
+        assert_equal(np.lcm(a, b), 10*big)
+
+    def test_gcd_overflow(self):
+        for dtype in (np.int32, np.int64):
+            # verify that we don't overflow when taking abs(x)
+            # not relevant for lcm, where the result is unrepresentable anyway
+            a = dtype(np.iinfo(dtype).min)  # negative power of two
+            q = -(a // 4)
+            assert_equal(np.gcd(a,  q*3), q)
+            assert_equal(np.gcd(a, -q*3), q)
+
+    def test_decimal(self):
+        from decimal import Decimal
+        a = np.array([1,  1, -1, -1]) * Decimal('0.20')
+        b = np.array([1, -1,  1, -1]) * Decimal('0.12')
+
+        assert_equal(np.gcd(a, b), 4*[Decimal('0.04')])
+        assert_equal(np.lcm(a, b), 4*[Decimal('0.60')])
+
+    def test_float(self):
+        # not well-defined on float due to rounding errors
+        assert_raises(TypeError, np.gcd, 0.3, 0.4)
+        assert_raises(TypeError, np.lcm, 0.3, 0.4)
+
+    def test_builtin_long(self):
+        # sanity check that array coercion is alright for builtin longs
+        assert_equal(np.array(2**200).item(), 2**200)
+
+        # expressed as prime factors
+        a = np.array(2**100 * 3**5)
+        b = np.array([2**100 * 5**7, 2**50 * 3**10])
+        assert_equal(np.gcd(a, b), [2**100,               2**50 * 3**5])
+        assert_equal(np.lcm(a, b), [2**100 * 3**5 * 5**7, 2**100 * 3**10])
+
+        assert_equal(np.gcd(2**100, 3**100), 1)
+
+
+class TestRoundingFunctions:
+
+    def test_object_direct(self):
+        """ test direct implementation of these magic methods """
+        class C:
+            def __floor__(self):
+                return 1
+            def __ceil__(self):
+                return 2
+            def __trunc__(self):
+                return 3
+
+        arr = np.array([C(), C()])
+        assert_equal(np.floor(arr), [1, 1])
+        assert_equal(np.ceil(arr),  [2, 2])
+        assert_equal(np.trunc(arr), [3, 3])
+
+    def test_object_indirect(self):
+        """ test implementations via __float__ """
+        class C:
+            def __float__(self):
+                return -2.5
+
+        arr = np.array([C(), C()])
+        assert_equal(np.floor(arr), [-3, -3])
+        assert_equal(np.ceil(arr),  [-2, -2])
+        with pytest.raises(TypeError):
+            np.trunc(arr)  # consistent with math.trunc
+
+    def test_fraction(self):
+        f = Fraction(-4, 3)
+        assert_equal(np.floor(f), -2)
+        assert_equal(np.ceil(f), -1)
+        assert_equal(np.trunc(f), -1)
+
+
+class TestComplexFunctions:
+    funcs = [np.arcsin,  np.arccos,  np.arctan, np.arcsinh, np.arccosh,
+             np.arctanh, np.sin,     np.cos,    np.tan,     np.exp,
+             np.exp2,    np.log,     np.sqrt,   np.log10,   np.log2,
+             np.log1p]
+
+    def test_it(self):
+        for f in self.funcs:
+            if f is np.arccosh:
+                x = 1.5
+            else:
+                x = .5
+            fr = f(x)
+            fz = f(complex(x))
+            assert_almost_equal(fz.real, fr, err_msg='real part %s' % f)
+            assert_almost_equal(fz.imag, 0., err_msg='imag part %s' % f)
+
+    @pytest.mark.xfail(IS_MUSL, reason="gh23049")
+    @pytest.mark.xfail(IS_WASM, reason="doesn't work")
+    def test_precisions_consistent(self):
+        z = 1 + 1j
+        for f in self.funcs:
+            fcf = f(np.csingle(z))
+            fcd = f(np.cdouble(z))
+            fcl = f(np.clongdouble(z))
+            assert_almost_equal(fcf, fcd, decimal=6, err_msg='fch-fcd %s' % f)
+            assert_almost_equal(fcl, fcd, decimal=15, err_msg='fch-fcl %s' % f)
+
+    @pytest.mark.xfail(IS_MUSL, reason="gh23049")
+    @pytest.mark.xfail(IS_WASM, reason="doesn't work")
+    def test_branch_cuts(self):
+        # check branch cuts and continuity on them
+        _check_branch_cut(np.log,   -0.5, 1j, 1, -1, True)
+        _check_branch_cut(np.log2,  -0.5, 1j, 1, -1, True)
+        _check_branch_cut(np.log10, -0.5, 1j, 1, -1, True)
+        _check_branch_cut(np.log1p, -1.5, 1j, 1, -1, True)
+        _check_branch_cut(np.sqrt,  -0.5, 1j, 1, -1, True)
+
+        _check_branch_cut(np.arcsin, [ -2, 2],   [1j, 1j], 1, -1, True)
+        _check_branch_cut(np.arccos, [ -2, 2],   [1j, 1j], 1, -1, True)
+        _check_branch_cut(np.arctan, [0-2j, 2j],  [1,  1], -1, 1, True)
+
+        _check_branch_cut(np.arcsinh, [0-2j,  2j], [1,   1], -1, 1, True)
+        _check_branch_cut(np.arccosh, [ -1, 0.5], [1j,  1j], 1, -1, True)
+        _check_branch_cut(np.arctanh, [ -2,   2], [1j, 1j], 1, -1, True)
+
+        # check against bogus branch cuts: assert continuity between quadrants
+        _check_branch_cut(np.arcsin, [0-2j, 2j], [ 1,  1], 1, 1)
+        _check_branch_cut(np.arccos, [0-2j, 2j], [ 1,  1], 1, 1)
+        _check_branch_cut(np.arctan, [ -2,  2], [1j, 1j], 1, 1)
+
+        _check_branch_cut(np.arcsinh, [ -2,  2, 0], [1j, 1j, 1], 1, 1)
+        _check_branch_cut(np.arccosh, [0-2j, 2j, 2], [1,  1,  1j], 1, 1)
+        _check_branch_cut(np.arctanh, [0-2j, 2j, 0], [1,  1,  1j], 1, 1)
+
+    @pytest.mark.xfail(IS_MUSL, reason="gh23049")
+    @pytest.mark.xfail(IS_WASM, reason="doesn't work")
+    def test_branch_cuts_complex64(self):
+        # check branch cuts and continuity on them
+        _check_branch_cut(np.log,   -0.5, 1j, 1, -1, True, np.complex64)
+        _check_branch_cut(np.log2,  -0.5, 1j, 1, -1, True, np.complex64)
+        _check_branch_cut(np.log10, -0.5, 1j, 1, -1, True, np.complex64)
+        _check_branch_cut(np.log1p, -1.5, 1j, 1, -1, True, np.complex64)
+        _check_branch_cut(np.sqrt,  -0.5, 1j, 1, -1, True, np.complex64)
+
+        _check_branch_cut(np.arcsin, [ -2, 2],   [1j, 1j], 1, -1, True, np.complex64)
+        _check_branch_cut(np.arccos, [ -2, 2],   [1j, 1j], 1, -1, True, np.complex64)
+        _check_branch_cut(np.arctan, [0-2j, 2j],  [1,  1], -1, 1, True, np.complex64)
+
+        _check_branch_cut(np.arcsinh, [0-2j,  2j], [1,   1], -1, 1, True, np.complex64)
+        _check_branch_cut(np.arccosh, [ -1, 0.5], [1j,  1j], 1, -1, True, np.complex64)
+        _check_branch_cut(np.arctanh, [ -2,   2], [1j, 1j], 1, -1, True, np.complex64)
+
+        # check against bogus branch cuts: assert continuity between quadrants
+        _check_branch_cut(np.arcsin, [0-2j, 2j], [ 1,  1], 1, 1, False, np.complex64)
+        _check_branch_cut(np.arccos, [0-2j, 2j], [ 1,  1], 1, 1, False, np.complex64)
+        _check_branch_cut(np.arctan, [ -2,  2], [1j, 1j], 1, 1, False, np.complex64)
+
+        _check_branch_cut(np.arcsinh, [ -2,  2, 0], [1j, 1j, 1], 1, 1, False, np.complex64)
+        _check_branch_cut(np.arccosh, [0-2j, 2j, 2], [1,  1,  1j], 1, 1, False, np.complex64)
+        _check_branch_cut(np.arctanh, [0-2j, 2j, 0], [1,  1,  1j], 1, 1, False, np.complex64)
+
+    def test_against_cmath(self):
+        import cmath
+
+        points = [-1-1j, -1+1j, +1-1j, +1+1j]
+        name_map = {'arcsin': 'asin', 'arccos': 'acos', 'arctan': 'atan',
+                    'arcsinh': 'asinh', 'arccosh': 'acosh', 'arctanh': 'atanh'}
+        atol = 4*np.finfo(complex).eps
+        for func in self.funcs:
+            fname = func.__name__.split('.')[-1]
+            cname = name_map.get(fname, fname)
+            try:
+                cfunc = getattr(cmath, cname)
+            except AttributeError:
+                continue
+            for p in points:
+                a = complex(func(np.complex_(p)))
+                b = cfunc(p)
+                assert_(
+                    abs(a - b) < atol,
+                    "%s %s: %s; cmath: %s" % (fname, p, a, b)
+                )
+
+    @pytest.mark.xfail(
+        # manylinux2014 uses glibc2.17
+        _glibc_older_than("2.18"),
+        reason="Older glibc versions are imprecise (maybe passes with SIMD?)"
+    )
+    @pytest.mark.xfail(IS_MUSL, reason="gh23049")
+    @pytest.mark.xfail(IS_WASM, reason="doesn't work")
+    @pytest.mark.parametrize('dtype', [np.complex64, np.complex_, np.longcomplex])
+    def test_loss_of_precision(self, dtype):
+        """Check loss of precision in complex arc* functions"""
+
+        # Check against known-good functions
+
+        info = np.finfo(dtype)
+        real_dtype = dtype(0.).real.dtype
+        eps = info.eps
+
+        def check(x, rtol):
+            x = x.astype(real_dtype)
+
+            z = x.astype(dtype)
+            d = np.absolute(np.arcsinh(x)/np.arcsinh(z).real - 1)
+            assert_(np.all(d < rtol), (np.argmax(d), x[np.argmax(d)], d.max(),
+                                      'arcsinh'))
+
+            z = (1j*x).astype(dtype)
+            d = np.absolute(np.arcsinh(x)/np.arcsin(z).imag - 1)
+            assert_(np.all(d < rtol), (np.argmax(d), x[np.argmax(d)], d.max(),
+                                      'arcsin'))
+
+            z = x.astype(dtype)
+            d = np.absolute(np.arctanh(x)/np.arctanh(z).real - 1)
+            assert_(np.all(d < rtol), (np.argmax(d), x[np.argmax(d)], d.max(),
+                                      'arctanh'))
+
+            z = (1j*x).astype(dtype)
+            d = np.absolute(np.arctanh(x)/np.arctan(z).imag - 1)
+            assert_(np.all(d < rtol), (np.argmax(d), x[np.argmax(d)], d.max(),
+                                      'arctan'))
+
+        # The switchover was chosen as 1e-3; hence there can be up to
+        # ~eps/1e-3 of relative cancellation error before it
+
+        x_series = np.logspace(-20, -3.001, 200)
+        x_basic = np.logspace(-2.999, 0, 10, endpoint=False)
+
+        if dtype is np.longcomplex:
+            if bad_arcsinh():
+                pytest.skip("Trig functions of np.longcomplex values known "
+                            "to be inaccurate on aarch64 and PPC for some "
+                            "compilation configurations.")
+            # It's not guaranteed that the system-provided arc functions
+            # are accurate down to a few epsilons. (Eg. on Linux 64-bit)
+            # So, give more leeway for long complex tests here:
+            check(x_series, 50.0*eps)
+        else:
+            check(x_series, 2.1*eps)
+        check(x_basic, 2.0*eps/1e-3)
+
+        # Check a few points
+
+        z = np.array([1e-5*(1+1j)], dtype=dtype)
+        p = 9.999999999333333333e-6 + 1.000000000066666666e-5j
+        d = np.absolute(1-np.arctanh(z)/p)
+        assert_(np.all(d < 1e-15))
+
+        p = 1.0000000000333333333e-5 + 9.999999999666666667e-6j
+        d = np.absolute(1-np.arcsinh(z)/p)
+        assert_(np.all(d < 1e-15))
+
+        p = 9.999999999333333333e-6j + 1.000000000066666666e-5
+        d = np.absolute(1-np.arctan(z)/p)
+        assert_(np.all(d < 1e-15))
+
+        p = 1.0000000000333333333e-5j + 9.999999999666666667e-6
+        d = np.absolute(1-np.arcsin(z)/p)
+        assert_(np.all(d < 1e-15))
+
+        # Check continuity across switchover points
+
+        def check(func, z0, d=1):
+            z0 = np.asarray(z0, dtype=dtype)
+            zp = z0 + abs(z0) * d * eps * 2
+            zm = z0 - abs(z0) * d * eps * 2
+            assert_(np.all(zp != zm), (zp, zm))
+
+            # NB: the cancellation error at the switchover is at least eps
+            good = (abs(func(zp) - func(zm)) < 2*eps)
+            assert_(np.all(good), (func, z0[~good]))
+
+        for func in (np.arcsinh, np.arcsinh, np.arcsin, np.arctanh, np.arctan):
+            pts = [rp+1j*ip for rp in (-1e-3, 0, 1e-3) for ip in(-1e-3, 0, 1e-3)
+                   if rp != 0 or ip != 0]
+            check(func, pts, 1)
+            check(func, pts, 1j)
+            check(func, pts, 1+1j)
+
+    @np.errstate(all="ignore")
+    def test_promotion_corner_cases(self):
+        for func in self.funcs:
+            assert func(np.float16(1)).dtype == np.float16
+            # Integer to low precision float promotion is a dubious choice:
+            assert func(np.uint8(1)).dtype == np.float16
+            assert func(np.int16(1)).dtype == np.float32
+
+
+class TestAttributes:
+    def test_attributes(self):
+        add = ncu.add
+        assert_equal(add.__name__, 'add')
+        assert_(add.ntypes >= 18)  # don't fail if types added
+        assert_('ii->i' in add.types)
+        assert_equal(add.nin, 2)
+        assert_equal(add.nout, 1)
+        assert_equal(add.identity, 0)
+
+    def test_doc(self):
+        # don't bother checking the long list of kwargs, which are likely to
+        # change
+        assert_(ncu.add.__doc__.startswith(
+            "add(x1, x2, /, out=None, *, where=True"))
+        assert_(ncu.frexp.__doc__.startswith(
+            "frexp(x[, out1, out2], / [, out=(None, None)], *, where=True"))
+
+
+class TestSubclass:
+
+    def test_subclass_op(self):
+
+        class simple(np.ndarray):
+            def __new__(subtype, shape):
+                self = np.ndarray.__new__(subtype, shape, dtype=object)
+                self.fill(0)
+                return self
+
+        a = simple((3, 4))
+        assert_equal(a+a, a)
+
+
+class TestFrompyfunc:
+
+    def test_identity(self):
+        def mul(a, b):
+            return a * b
+
+        # with identity=value
+        mul_ufunc = np.frompyfunc(mul, nin=2, nout=1, identity=1)
+        assert_equal(mul_ufunc.reduce([2, 3, 4]), 24)
+        assert_equal(mul_ufunc.reduce(np.ones((2, 2)), axis=(0, 1)), 1)
+        assert_equal(mul_ufunc.reduce([]), 1)
+
+        # with identity=None (reorderable)
+        mul_ufunc = np.frompyfunc(mul, nin=2, nout=1, identity=None)
+        assert_equal(mul_ufunc.reduce([2, 3, 4]), 24)
+        assert_equal(mul_ufunc.reduce(np.ones((2, 2)), axis=(0, 1)), 1)
+        assert_raises(ValueError, lambda: mul_ufunc.reduce([]))
+
+        # with no identity (not reorderable)
+        mul_ufunc = np.frompyfunc(mul, nin=2, nout=1)
+        assert_equal(mul_ufunc.reduce([2, 3, 4]), 24)
+        assert_raises(ValueError, lambda: mul_ufunc.reduce(np.ones((2, 2)), axis=(0, 1)))
+        assert_raises(ValueError, lambda: mul_ufunc.reduce([]))
+
+
+def _check_branch_cut(f, x0, dx, re_sign=1, im_sign=-1, sig_zero_ok=False,
+                      dtype=complex):
+    """
+    Check for a branch cut in a function.
+
+    Assert that `x0` lies on a branch cut of function `f` and `f` is
+    continuous from the direction `dx`.
+
+    Parameters
+    ----------
+    f : func
+        Function to check
+    x0 : array-like
+        Point on branch cut
+    dx : array-like
+        Direction to check continuity in
+    re_sign, im_sign : {1, -1}
+        Change of sign of the real or imaginary part expected
+    sig_zero_ok : bool
+        Whether to check if the branch cut respects signed zero (if applicable)
+    dtype : dtype
+        Dtype to check (should be complex)
+
+    """
+    x0 = np.atleast_1d(x0).astype(dtype)
+    dx = np.atleast_1d(dx).astype(dtype)
+
+    if np.dtype(dtype).char == 'F':
+        scale = np.finfo(dtype).eps * 1e2
+        atol = np.float32(1e-2)
+    else:
+        scale = np.finfo(dtype).eps * 1e3
+        atol = 1e-4
+
+    y0 = f(x0)
+    yp = f(x0 + dx*scale*np.absolute(x0)/np.absolute(dx))
+    ym = f(x0 - dx*scale*np.absolute(x0)/np.absolute(dx))
+
+    assert_(np.all(np.absolute(y0.real - yp.real) < atol), (y0, yp))
+    assert_(np.all(np.absolute(y0.imag - yp.imag) < atol), (y0, yp))
+    assert_(np.all(np.absolute(y0.real - ym.real*re_sign) < atol), (y0, ym))
+    assert_(np.all(np.absolute(y0.imag - ym.imag*im_sign) < atol), (y0, ym))
+
+    if sig_zero_ok:
+        # check that signed zeros also work as a displacement
+        jr = (x0.real == 0) & (dx.real != 0)
+        ji = (x0.imag == 0) & (dx.imag != 0)
+        if np.any(jr):
+            x = x0[jr]
+            x.real = np.NZERO
+            ym = f(x)
+            assert_(np.all(np.absolute(y0[jr].real - ym.real*re_sign) < atol), (y0[jr], ym))
+            assert_(np.all(np.absolute(y0[jr].imag - ym.imag*im_sign) < atol), (y0[jr], ym))
+
+        if np.any(ji):
+            x = x0[ji]
+            x.imag = np.NZERO
+            ym = f(x)
+            assert_(np.all(np.absolute(y0[ji].real - ym.real*re_sign) < atol), (y0[ji], ym))
+            assert_(np.all(np.absolute(y0[ji].imag - ym.imag*im_sign) < atol), (y0[ji], ym))
+
+def test_copysign():
+    assert_(np.copysign(1, -1) == -1)
+    with np.errstate(divide="ignore"):
+        assert_(1 / np.copysign(0, -1) < 0)
+        assert_(1 / np.copysign(0, 1) > 0)
+    assert_(np.signbit(np.copysign(np.nan, -1)))
+    assert_(not np.signbit(np.copysign(np.nan, 1)))
+
+def _test_nextafter(t):
+    one = t(1)
+    two = t(2)
+    zero = t(0)
+    eps = np.finfo(t).eps
+    assert_(np.nextafter(one, two) - one == eps)
+    assert_(np.nextafter(one, zero) - one < 0)
+    assert_(np.isnan(np.nextafter(np.nan, one)))
+    assert_(np.isnan(np.nextafter(one, np.nan)))
+    assert_(np.nextafter(one, one) == one)
+
+def test_nextafter():
+    return _test_nextafter(np.float64)
+
+
+def test_nextafterf():
+    return _test_nextafter(np.float32)
+
+
+@pytest.mark.skipif(np.finfo(np.double) == np.finfo(np.longdouble),
+                    reason="long double is same as double")
+@pytest.mark.xfail(condition=platform.machine().startswith("ppc64"),
+                    reason="IBM double double")
+def test_nextafterl():
+    return _test_nextafter(np.longdouble)
+
+
+def test_nextafter_0():
+    for t, direction in itertools.product(np.sctypes['float'], (1, -1)):
+        # The value of tiny for double double is NaN, so we need to pass the
+        # assert
+        with suppress_warnings() as sup:
+            sup.filter(UserWarning)
+            if not np.isnan(np.finfo(t).tiny):
+                tiny = np.finfo(t).tiny
+                assert_(
+                    0. < direction * np.nextafter(t(0), t(direction)) < tiny)
+        assert_equal(np.nextafter(t(0), t(direction)) / t(2.1), direction * 0.0)
+
+def _test_spacing(t):
+    one = t(1)
+    eps = np.finfo(t).eps
+    nan = t(np.nan)
+    inf = t(np.inf)
+    with np.errstate(invalid='ignore'):
+        assert_equal(np.spacing(one), eps)
+        assert_(np.isnan(np.spacing(nan)))
+        assert_(np.isnan(np.spacing(inf)))
+        assert_(np.isnan(np.spacing(-inf)))
+        assert_(np.spacing(t(1e30)) != 0)
+
+def test_spacing():
+    return _test_spacing(np.float64)
+
+def test_spacingf():
+    return _test_spacing(np.float32)
+
+
+@pytest.mark.skipif(np.finfo(np.double) == np.finfo(np.longdouble),
+                    reason="long double is same as double")
+@pytest.mark.xfail(condition=platform.machine().startswith("ppc64"),
+                    reason="IBM double double")
+def test_spacingl():
+    return _test_spacing(np.longdouble)
+
+def test_spacing_gfortran():
+    # Reference from this fortran file, built with gfortran 4.3.3 on linux
+    # 32bits:
+    #       PROGRAM test_spacing
+    #        INTEGER, PARAMETER :: SGL = SELECTED_REAL_KIND(p=6, r=37)
+    #        INTEGER, PARAMETER :: DBL = SELECTED_REAL_KIND(p=13, r=200)
+    #
+    #        WRITE(*,*) spacing(0.00001_DBL)
+    #        WRITE(*,*) spacing(1.0_DBL)
+    #        WRITE(*,*) spacing(1000._DBL)
+    #        WRITE(*,*) spacing(10500._DBL)
+    #
+    #        WRITE(*,*) spacing(0.00001_SGL)
+    #        WRITE(*,*) spacing(1.0_SGL)
+    #        WRITE(*,*) spacing(1000._SGL)
+    #        WRITE(*,*) spacing(10500._SGL)
+    #       END PROGRAM
+    ref = {np.float64: [1.69406589450860068E-021,
+                        2.22044604925031308E-016,
+                        1.13686837721616030E-013,
+                        1.81898940354585648E-012],
+           np.float32: [9.09494702E-13,
+                        1.19209290E-07,
+                        6.10351563E-05,
+                        9.76562500E-04]}
+
+    for dt, dec_ in zip([np.float32, np.float64], (10, 20)):
+        x = np.array([1e-5, 1, 1000, 10500], dtype=dt)
+        assert_array_almost_equal(np.spacing(x), ref[dt], decimal=dec_)
+
+def test_nextafter_vs_spacing():
+    # XXX: spacing does not handle long double yet
+    for t in [np.float32, np.float64]:
+        for _f in [1, 1e-5, 1000]:
+            f = t(_f)
+            f1 = t(_f + 1)
+            assert_(np.nextafter(f, f1) - f == np.spacing(f))
+
+def test_pos_nan():
+    """Check np.nan is a positive nan."""
+    assert_(np.signbit(np.nan) == 0)
+
+def test_reduceat():
+    """Test bug in reduceat when structured arrays are not copied."""
+    db = np.dtype([('name', 'S11'), ('time', np.int64), ('value', np.float32)])
+    a = np.empty([100], dtype=db)
+    a['name'] = 'Simple'
+    a['time'] = 10
+    a['value'] = 100
+    indx = [0, 7, 15, 25]
+
+    h2 = []
+    val1 = indx[0]
+    for val2 in indx[1:]:
+        h2.append(np.add.reduce(a['value'][val1:val2]))
+        val1 = val2
+    h2.append(np.add.reduce(a['value'][val1:]))
+    h2 = np.array(h2)
+
+    # test buffered -- this should work
+    h1 = np.add.reduceat(a['value'], indx)
+    assert_array_almost_equal(h1, h2)
+
+    # This is when the error occurs.
+    # test no buffer
+    np.setbufsize(32)
+    h1 = np.add.reduceat(a['value'], indx)
+    np.setbufsize(np.UFUNC_BUFSIZE_DEFAULT)
+    assert_array_almost_equal(h1, h2)
+
+def test_reduceat_empty():
+    """Reduceat should work with empty arrays"""
+    indices = np.array([], 'i4')
+    x = np.array([], 'f8')
+    result = np.add.reduceat(x, indices)
+    assert_equal(result.dtype, x.dtype)
+    assert_equal(result.shape, (0,))
+    # Another case with a slightly different zero-sized shape
+    x = np.ones((5, 2))
+    result = np.add.reduceat(x, [], axis=0)
+    assert_equal(result.dtype, x.dtype)
+    assert_equal(result.shape, (0, 2))
+    result = np.add.reduceat(x, [], axis=1)
+    assert_equal(result.dtype, x.dtype)
+    assert_equal(result.shape, (5, 0))
+
+def test_complex_nan_comparisons():
+    nans = [complex(np.nan, 0), complex(0, np.nan), complex(np.nan, np.nan)]
+    fins = [complex(1, 0), complex(-1, 0), complex(0, 1), complex(0, -1),
+            complex(1, 1), complex(-1, -1), complex(0, 0)]
+
+    with np.errstate(invalid='ignore'):
+        for x in nans + fins:
+            x = np.array([x])
+            for y in nans + fins:
+                y = np.array([y])
+
+                if np.isfinite(x) and np.isfinite(y):
+                    continue
+
+                assert_equal(x < y, False, err_msg="%r < %r" % (x, y))
+                assert_equal(x > y, False, err_msg="%r > %r" % (x, y))
+                assert_equal(x <= y, False, err_msg="%r <= %r" % (x, y))
+                assert_equal(x >= y, False, err_msg="%r >= %r" % (x, y))
+                assert_equal(x == y, False, err_msg="%r == %r" % (x, y))
+
+
+def test_rint_big_int():
+    # np.rint bug for large integer values on Windows 32-bit and MKL
+    # https://github.com/numpy/numpy/issues/6685
+    val = 4607998452777363968
+    # This is exactly representable in floating point
+    assert_equal(val, int(float(val)))
+    # Rint should not change the value
+    assert_equal(val, np.rint(val))
+
+
+@pytest.mark.parametrize('ftype', [np.float32, np.float64])
+def test_memoverlap_accumulate(ftype):
+    # Reproduces bug https://github.com/numpy/numpy/issues/15597
+    arr = np.array([0.61, 0.60, 0.77, 0.41, 0.19], dtype=ftype)
+    out_max = np.array([0.61, 0.61, 0.77, 0.77, 0.77], dtype=ftype)
+    out_min = np.array([0.61, 0.60, 0.60, 0.41, 0.19], dtype=ftype)
+    assert_equal(np.maximum.accumulate(arr), out_max)
+    assert_equal(np.minimum.accumulate(arr), out_min)
+
+@pytest.mark.parametrize("ufunc, dtype", [
+    (ufunc, t[0])
+    for ufunc in UFUNCS_BINARY_ACC
+    for t in ufunc.types
+    if t[-1] == '?' and t[0] not in 'DFGMmO'
+])
+def test_memoverlap_accumulate_cmp(ufunc, dtype):
+    if ufunc.signature:
+        pytest.skip('For generic signatures only')
+    for size in (2, 8, 32, 64, 128, 256):
+        arr = np.array([0, 1, 1]*size, dtype=dtype)
+        acc = ufunc.accumulate(arr, dtype='?')
+        acc_u8 = acc.view(np.uint8)
+        exp = np.array(list(itertools.accumulate(arr, ufunc)), dtype=np.uint8)
+        assert_equal(exp, acc_u8)
+
+@pytest.mark.parametrize("ufunc, dtype", [
+    (ufunc, t[0])
+    for ufunc in UFUNCS_BINARY_ACC
+    for t in ufunc.types
+    if t[0] == t[1] and t[0] == t[-1] and t[0] not in 'DFGMmO?'
+])
+def test_memoverlap_accumulate_symmetric(ufunc, dtype):
+    if ufunc.signature:
+        pytest.skip('For generic signatures only')
+    with np.errstate(all='ignore'):
+        for size in (2, 8, 32, 64, 128, 256):
+            arr = np.array([0, 1, 2]*size).astype(dtype)
+            acc = ufunc.accumulate(arr, dtype=dtype)
+            exp = np.array(list(itertools.accumulate(arr, ufunc)), dtype=dtype)
+            assert_equal(exp, acc)
+
+def test_signaling_nan_exceptions():
+    with assert_no_warnings():
+        a = np.ndarray(shape=(), dtype='float32', buffer=b'\x00\xe0\xbf\xff')
+        np.isnan(a)
+
+@pytest.mark.parametrize("arr", [
+    np.arange(2),
+    np.matrix([0, 1]),
+    np.matrix([[0, 1], [2, 5]]),
+    ])
+def test_outer_subclass_preserve(arr):
+    # for gh-8661
+    class foo(np.ndarray): pass
+    actual = np.multiply.outer(arr.view(foo), arr.view(foo))
+    assert actual.__class__.__name__ == 'foo'
+
+def test_outer_bad_subclass():
+    class BadArr1(np.ndarray):
+        def __array_finalize__(self, obj):
+            # The outer call reshapes to 3 dims, try to do a bad reshape.
+            if self.ndim == 3:
+                self.shape = self.shape + (1,)
+
+        def __array_prepare__(self, obj, context=None):
+            return obj
+
+    class BadArr2(np.ndarray):
+        def __array_finalize__(self, obj):
+            if isinstance(obj, BadArr2):
+                # outer inserts 1-sized dims. In that case disturb them.
+                if self.shape[-1] == 1:
+                    self.shape = self.shape[::-1]
+
+        def __array_prepare__(self, obj, context=None):
+            return obj
+
+    for cls in [BadArr1, BadArr2]:
+        arr = np.ones((2, 3)).view(cls)
+        with assert_raises(TypeError) as a:
+            # The first array gets reshaped (not the second one)
+            np.add.outer(arr, [1, 2])
+
+        # This actually works, since we only see the reshaping error:
+        arr = np.ones((2, 3)).view(cls)
+        assert type(np.add.outer([1, 2], arr)) is cls
+
+def test_outer_exceeds_maxdims():
+    deep = np.ones((1,) * 17)
+    with assert_raises(ValueError):
+        np.add.outer(deep, deep)
+
+def test_bad_legacy_ufunc_silent_errors():
+    # legacy ufuncs can't report errors and NumPy can't check if the GIL
+    # is released.  So NumPy has to check after the GIL is released just to
+    # cover all bases.  `np.power` uses/used to use this.
+    arr = np.arange(3).astype(np.float64)
+
+    with pytest.raises(RuntimeError, match=r"How unexpected :\)!"):
+        ncu_tests.always_error(arr, arr)
+
+    with pytest.raises(RuntimeError, match=r"How unexpected :\)!"):
+        # not contiguous means the fast-path cannot be taken
+        non_contig = arr.repeat(20).reshape(-1, 6)[:, ::2]
+        ncu_tests.always_error(non_contig, arr)
+
+    with pytest.raises(RuntimeError, match=r"How unexpected :\)!"):
+        ncu_tests.always_error.outer(arr, arr)
+
+    with pytest.raises(RuntimeError, match=r"How unexpected :\)!"):
+        ncu_tests.always_error.reduce(arr)
+
+    with pytest.raises(RuntimeError, match=r"How unexpected :\)!"):
+        ncu_tests.always_error.reduceat(arr, [0, 1])
+
+    with pytest.raises(RuntimeError, match=r"How unexpected :\)!"):
+        ncu_tests.always_error.accumulate(arr)
+
+    with pytest.raises(RuntimeError, match=r"How unexpected :\)!"):
+        ncu_tests.always_error.at(arr, [0, 1, 2], arr)
+
+
+@pytest.mark.parametrize('x1', [np.arange(3.0), [0.0, 1.0, 2.0]])
+def test_bad_legacy_gufunc_silent_errors(x1):
+    # Verify that an exception raised in a gufunc loop propagates correctly.
+    # The signature of always_error_gufunc is '(i),()->()'.
+    with pytest.raises(RuntimeError, match=r"How unexpected :\)!"):
+        ncu_tests.always_error_gufunc(x1, 0.0)