[Numpy-discussion] treating numpy arrays like lists is slow

[Jeff W. <js...@fa...>]

Hi:

I've noticed that code like this is really slow in numpy (0.9.4):

import numpy as NP
a = NP.ones(10000,'d')
a = [2.*a1 for a1 in a]


the last line takes 0.17 seconds on my G5, while for Numeric and 
numarray it takes only 0.01.  Anyone know the reason for this?

-Jeff

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