[Numpy-discussion] Negative indexing.

Daniele Nicolodi daniele at grinta.net
Sun Jan 15 07:30:33 EST 2012

On 15/01/12 00:53, Nathan Faggian wrote:
> Hi,
> I am finding it less than useful to have the negative index wrapping
> on nd-arrays. Here is a short example:
> import numpy as np
> a = np.zeros((3, 3))
> a[:,2] = 1000
> print a[0,-1]
> print a[0,-1]
> print a[-1,-1]
> In all cases 1000 is printed out. 

What else would you expect?

> What I am after is a way to say "please don't wrap around" and have
> negative indices behave in a way I choose.  I know this is a standard
> thing - but is there a way to override that behaviour that doesn't
> involve cython or rolling my own resampler?

What other behavior would you choose? I don't see any other that would
make sense and that would be consistent with positive indexing.


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