diff options
Diffstat (limited to '.venv/lib/python3.12/site-packages/numpy/random/_examples/numba/extending.py')
-rw-r--r-- | .venv/lib/python3.12/site-packages/numpy/random/_examples/numba/extending.py | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/numpy/random/_examples/numba/extending.py b/.venv/lib/python3.12/site-packages/numpy/random/_examples/numba/extending.py new file mode 100644 index 00000000..f387db69 --- /dev/null +++ b/.venv/lib/python3.12/site-packages/numpy/random/_examples/numba/extending.py @@ -0,0 +1,84 @@ +import numpy as np +import numba as nb + +from numpy.random import PCG64 +from timeit import timeit + +bit_gen = PCG64() +next_d = bit_gen.cffi.next_double +state_addr = bit_gen.cffi.state_address + +def normals(n, state): + out = np.empty(n) + for i in range((n + 1) // 2): + x1 = 2.0 * next_d(state) - 1.0 + x2 = 2.0 * next_d(state) - 1.0 + r2 = x1 * x1 + x2 * x2 + while r2 >= 1.0 or r2 == 0.0: + x1 = 2.0 * next_d(state) - 1.0 + x2 = 2.0 * next_d(state) - 1.0 + r2 = x1 * x1 + x2 * x2 + f = np.sqrt(-2.0 * np.log(r2) / r2) + out[2 * i] = f * x1 + if 2 * i + 1 < n: + out[2 * i + 1] = f * x2 + return out + +# Compile using Numba +normalsj = nb.jit(normals, nopython=True) +# Must use state address not state with numba +n = 10000 + +def numbacall(): + return normalsj(n, state_addr) + +rg = np.random.Generator(PCG64()) + +def numpycall(): + return rg.normal(size=n) + +# Check that the functions work +r1 = numbacall() +r2 = numpycall() +assert r1.shape == (n,) +assert r1.shape == r2.shape + +t1 = timeit(numbacall, number=1000) +print(f'{t1:.2f} secs for {n} PCG64 (Numba/PCG64) gaussian randoms') +t2 = timeit(numpycall, number=1000) +print(f'{t2:.2f} secs for {n} PCG64 (NumPy/PCG64) gaussian randoms') + +# example 2 + +next_u32 = bit_gen.ctypes.next_uint32 +ctypes_state = bit_gen.ctypes.state + +@nb.jit(nopython=True) +def bounded_uint(lb, ub, state): + mask = delta = ub - lb + mask |= mask >> 1 + mask |= mask >> 2 + mask |= mask >> 4 + mask |= mask >> 8 + mask |= mask >> 16 + + val = next_u32(state) & mask + while val > delta: + val = next_u32(state) & mask + + return lb + val + + +print(bounded_uint(323, 2394691, ctypes_state.value)) + + +@nb.jit(nopython=True) +def bounded_uints(lb, ub, n, state): + out = np.empty(n, dtype=np.uint32) + for i in range(n): + out[i] = bounded_uint(lb, ub, state) + + +bounded_uints(323, 2394691, 10000000, ctypes_state.value) + + |