[Numpy-discussion] np.{bool,float,int} deprecation

[Juan Nunez-Iglesias]

Hi all,

At the prodding [1] of Sebastian, I’m starting a discussion on the decision to deprecate np.{bool,float,int}. This deprecation broke our prerelease testing in scikit-image (which, hooray for rcs!), and resulted in a large amount of code churn to fix [2].

To be honest, I do think *some* sort of deprecation is needed, because for the longest time I thought that np.float was what np.float_ actually is. I think it would be worthwhile to move to *that*, though it’s an even more invasive deprecation than the currently proposed one. Writing `x = np.zeros(5, dtype=int)` is somewhat magical, because someone with a strict typing mindset (there’s an increasing number!) might expect that this is an array of pointers to Python ints. This is why I’ve always preferred to write `dtype=np.int`, resulting in the current code churn.

I don’t know what the best answer is, just sparking the discussion Sebastian wants to see. ;) For skimage we’ve already merged a fix (even if it is one of dubious quality, as Stéfan points out [3] ;), so I don’t have too much stake in the outcome.

Juan.

[1]: https://github.com/scikit-image/scikit-image/pull/5103#issuecomment-739334463
[2]: https://github.com/scikit-image/scikit-image/pull/5103
[3]: https://github.com/scikit-image/scikit-image/pull/5103#issuecomment-739368765