Allow non-power-of-two nside values when the pixel scheme is RING

[tmolteno]

Hi There,

This PR changes the isnsideok() function to allow non-power-of-two nside values (when using the RING scheme). This is useful when searching for a pixelization scheme that is just high enough - which can lead to huge efficiencies in the situation where one is discretizing a small subset of the sphere at high resolution.

The test is somewhat application specific (to suit my needs) so apologies in advance for that.

Refers to Issue #583.

Tim

[zonca]

looks good, thank you very much!
just 1 minor point

[zonca]

what about having nest default to False?
That is common in all other functions that accept that argument.

[zonca]

also, there is another isnsideok method in pixelfunc.py...https://github.com/healpy/healpy/blob/master/healpy/pixelfunc.py#L1160
can you remove that so we always use the one defined in cython?

[tmolteno]

Hi There. I will make the default argument as you suggest. Good point about the duplicate in pixelfunc. Will submit another PR soon.

[tmolteno]

I have left the version in pixelfunc (suitably modified) as it seems a little more logical for isnsideok to be in the pixel functions (happy to shift it if necessary)

[zonca]

there is actually another one in pixelfunc.py https://github.com/healpy/healpy/blob/master/healpy/pixelfunc.py#L1160, can you remove that one as well?

[tmolteno]

Wow, there were three of them! The isnsideok() in https://github.com/healpy/healpy/blob/master/healpy/pixelfunc.py#L1160 is exported to the healpy module. Didn't see it there at all as I had my eyes down looking inside the .pyx files. I will leave that one and remove the one I modified in _pixelfunc.pyx (which has identical functionality, but has much uglier documentation.)

[zonca]

Thanks!