I'm trying to build a meshgrid with small nonnegative integers
default is int32
>>> np.meshgrid([0,1,2], [0,1])[0].dtype
dtype('int32')
If I use uint, then the arrays are upcast to int64 - Why?
>>> np.meshgrid(np.array([0,1,2], np.uint), np.array([0,1],
np.uint))[0].dtype
dtype('int64')
broadcast_arrays preserves dtype
>>> np.broadcast_arrays(np.array([0,1,2], np.uint)[:,None], np.array([0,1],
np.uint)[None, :])
[array([[0, 0],
[1, 1],
[2, 2]], dtype=uint32), array([[0, 1],
[0, 1],
[0, 1]], dtype=uint32)]
with uint8
>>> np.broadcast_arrays(np.array([0,1,2], np.uint8)[:,None],
np.array([0,1], np.uint8)[None, :])
[array([[0, 0],
[1, 1],
[2, 2]], dtype=uint8), array([[0, 1],
[0, 1],
[0, 1]], dtype=uint8)]
>>> np.meshgrid(np.array([0,1,2], np.uint8), np.array([0,1],
np.uint8))[0].dtype
dtype('int32')
>>>
Winpython 64 bit
>>> np.__version__
'1.9.2rc1'
Josef
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