diff options
Diffstat (limited to '.venv/lib/python3.12/site-packages/numpy/random/_examples/cython/extending.pyx')
-rw-r--r-- | .venv/lib/python3.12/site-packages/numpy/random/_examples/cython/extending.pyx | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/numpy/random/_examples/cython/extending.pyx b/.venv/lib/python3.12/site-packages/numpy/random/_examples/cython/extending.pyx new file mode 100644 index 00000000..30efd744 --- /dev/null +++ b/.venv/lib/python3.12/site-packages/numpy/random/_examples/cython/extending.pyx @@ -0,0 +1,78 @@ +#!/usr/bin/env python3 +#cython: language_level=3 + +from libc.stdint cimport uint32_t +from cpython.pycapsule cimport PyCapsule_IsValid, PyCapsule_GetPointer + +import numpy as np +cimport numpy as np +cimport cython + +from numpy.random cimport bitgen_t +from numpy.random import PCG64 + +np.import_array() + + +@cython.boundscheck(False) +@cython.wraparound(False) +def uniform_mean(Py_ssize_t n): + cdef Py_ssize_t i + cdef bitgen_t *rng + cdef const char *capsule_name = "BitGenerator" + cdef double[::1] random_values + cdef np.ndarray randoms + + x = PCG64() + capsule = x.capsule + if not PyCapsule_IsValid(capsule, capsule_name): + raise ValueError("Invalid pointer to anon_func_state") + rng = <bitgen_t *> PyCapsule_GetPointer(capsule, capsule_name) + random_values = np.empty(n) + # Best practice is to acquire the lock whenever generating random values. + # This prevents other threads from modifying the state. Acquiring the lock + # is only necessary if the GIL is also released, as in this example. + with x.lock, nogil: + for i in range(n): + random_values[i] = rng.next_double(rng.state) + randoms = np.asarray(random_values) + return randoms.mean() + + +# This function is declared nogil so it can be used without the GIL below +cdef uint32_t bounded_uint(uint32_t lb, uint32_t ub, bitgen_t *rng) nogil: + cdef uint32_t mask, delta, val + mask = delta = ub - lb + mask |= mask >> 1 + mask |= mask >> 2 + mask |= mask >> 4 + mask |= mask >> 8 + mask |= mask >> 16 + + val = rng.next_uint32(rng.state) & mask + while val > delta: + val = rng.next_uint32(rng.state) & mask + + return lb + val + + +@cython.boundscheck(False) +@cython.wraparound(False) +def bounded_uints(uint32_t lb, uint32_t ub, Py_ssize_t n): + cdef Py_ssize_t i + cdef bitgen_t *rng + cdef uint32_t[::1] out + cdef const char *capsule_name = "BitGenerator" + + x = PCG64() + out = np.empty(n, dtype=np.uint32) + capsule = x.capsule + + if not PyCapsule_IsValid(capsule, capsule_name): + raise ValueError("Invalid pointer to anon_func_state") + rng = <bitgen_t *>PyCapsule_GetPointer(capsule, capsule_name) + + with x.lock, nogil: + for i in range(n): + out[i] = bounded_uint(lb, ub, rng) + return np.asarray(out) |