Extending via CFFI — NumPy v2.3.dev0 Manual (original) (raw)

""" Use cffi to access any of the underlying C functions from distributions.h """ import os import numpy as np import cffi from .parse import parse_distributions_h ffi = cffi.FFI()

inc_dir = os.path.join(np.get_include(), 'numpy')

Basic numpy types

ffi.cdef(''' typedef intptr_t npy_intp; typedef unsigned char npy_bool;

''')

parse_distributions_h(ffi, inc_dir)

lib = ffi.dlopen(np.random._generator.file)

Compare the distributions.h random_standard_normal_fill to

Generator.standard_random

bit_gen = np.random.PCG64() rng = np.random.Generator(bit_gen) state = bit_gen.state

interface = rng.bit_generator.cffi n = 100 vals_cffi = ffi.new('double[%d]' % n) lib.random_standard_normal_fill(interface.bit_generator, n, vals_cffi)

reset the state

bit_gen.state = state

vals = rng.standard_normal(n)

for i in range(n): assert vals[i] == vals_cffi[i]