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cdef extern from "C_func_file.c":
# C is include here so that it doesn't need to be compiled externally
pass
cdef extern from "C_func_file.h":
void multiply_by_10_in_C(double *, unsigned int)
import numpy as np
def multiply_by_10(arr): # 'arr' is a one-dimensional numpy array
if not arr.flags['C_CONTIGUOUS']:
arr = np.ascontiguousarray(arr) # Makes a contiguous copy of the numpy array.
cdef double[::1] arr_memview = arr
multiply_by_10_in_C(&arr_memview[0], arr_memview.shape[0])
return arr
a = np.ones(5, dtype=np.double)
print(multiply_by_10(a))
b = np.ones(10, dtype=np.double)
b = b[::2] # b is not contiguous.
print(multiply_by_10(b)) # but our function still works as expected.
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