On Tue, Jan 29, 2013 at 10:05 PM, Juan Nunez-Iglesias <jni.soma@gmail.com>wrote:

Hi,

Does scikit-image have a specific policy for how imports should work? For example, as far as I know, numpy currently imports everything into the np namespace with:

import numpy as np

However, the following raises an error, even though the import statement works fine:

import skimage as skim coins = skim.data.coins()

giving the error:

--------------------------------------------------------------------------- AttributeError Traceback (most recent call last) <ipython-input-3-0ce27ef61295> in <module>() ----> 1 coins = skim.data.coins()

AttributeError: 'module' object has no attribute 'data'

But some things *are* in the top-level namespace. The following works fine:

import skimage as skimfrom skimage import data coins = data.coins() coins = skim.img_as_float(coins)

So my question is, is this behaviour by design, or should there be nothing at all in the top-level, or should everything be imported?

I tend to agree that it should be one or the other (with the exception of the standard metadata at the top-level). The argument against importing everything is that it can lead to slow import times (see, numpy for example<http://numpy-discussion.10968.n7.nabble.com/quot-import-numpy-quot-is-slow-t...>), even when you're only using a small subset of the package. While this time may not be too severe now, the hope is that scikit-image will grow ever-more functionality, which would slow import times. I'm in favor of moving the functionality out of the top level. I think the only thing that would need to be moved out would be the converters in `skimage.util.dtype`. There should be a shorter path to access those functions, though. Side note: I'm not a huge fan of `util` (I would have thought `utils`), but that's a minor point. And of course, if others agree, this would need to be phased in over time---probably with a couple of releases raising deprecation warnings when trying to access those functions at the top level. Also, this would wait until after the release of 0.8. -Tony