python - Loop over a Numpy array with Cython -


let a , b 2 numpy.float arrays of length 1024, defined with

cdef numpy.ndarray cdef numpy.ndarray b

i notice that:

cdef int in range(1024):     b[i] += a[i]

is considerably slower than:

b +=

why?

i need able loop manually on arrays.

the difference smaller if tell cython data type , number of dimensions a , b:

cdef numpy.ndarray[np.float64_t, ndim=1] a, b

although difference smaller, won't beat b += a because using numpy's simd-boosted functions (which perform depending if cpu supports simd).


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