Re: [Numpy-discussion] Contiguity of result of astype changed - intentional?

Hi, On Wed, Sep 12, 2012 at 10:24 PM, Ondřej Čertík wrote:

Hi Matt,

On Wed, Sep 12, 2012 at 1:27 PM, Travis Oliphant wrote:

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Is this intended? Is there a performance reason to keep the same strides in 1.7.0?

I believe that this could be because in 1.7.0, NumPy was changed so that copying does not always default to "C-order" but to "Keep-order". So, in 1.7.0, the strides of b is governed by the strides of a, while in 1.6.1, the strides of b is C-order (because of the copy).

Thanks for the reply.

So maybe the bottom line is that the user should not assume any contiguity from ``astype``? If that's the case I'll submit a docstring PR to say that.

Yes, that would be a great addition to the docstring. Mark, can you confirm this is the desired behavior? Ondrej, this would be something to put in the release notes, if it isn't already.

If you could submit the PR with the docs, that'd be awesome. In the meantime, I've created an issue for it:

https://github.com/numpy/numpy/issues/437

and put it into my TODO list:

https://github.com/numpy/numpy/issues/396

Sorry - inadequate research on my part - the current docstring for ``astype`` is clear and comprehensive, and the change was obviously intentional. Cheers, Matthew