[Numpy-discussion] Casting to np.byte before clearing values

[Nicolas P. Rougier]

Hi all,


I'm trying to understand why viewing an array as bytes before clearing makes the whole operation faster.
I imagine there is some kind of special treatment for byte arrays but I've no clue. 


# Native float
Z_float = np.ones(1000000, float)
Z_int   = np.ones(1000000, int)

%timeit Z_float[...] = 0
1000 loops, best of 3: 361 µs per loop

%timeit Z_int[...] = 0
1000 loops, best of 3: 366 µs per loop

%timeit Z_float.view(np.byte)[...] = 0
1000 loops, best of 3: 267 µs per loop

%timeit Z_int.view(np.byte)[...] = 0
1000 loops, best of 3: 266 µs per loop


Nicolas