docs/examples/tutorial/memory_allocation/malloc.pyx


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import random
from libc.stdlib cimport malloc, free

def random_noise(int number=1):
    cdef int i
    # allocate number * sizeof(double) bytes of memory
    cdef double *my_array = <double *> malloc(number * sizeof(double))
    if not my_array:
        raise MemoryError()

    try:
        ran = random.normalvariate
        for i in range(number):
            my_array[i] = ran(0, 1)

        # ... let's just assume we do some more heavy C calculations here to make up
        # for the work that it takes to pack the C double values into Python float
        # objects below, right after throwing away the existing objects above.

        return [x for x in my_array[:number]]
    finally:
        # return the previously allocated memory to the system
        free(my_array)