[AstroPy] Putting astronomy packages on PyPI

[Tom Aldcroft]

I see there has been some discussion previously on the idea of putting
packages on PyPI (in particular for vo-0.6).  There did not seem to
have been a resolution so I want to ask once more why it is not
possible or desirable to do so.

As background, over the last two months my colleagues and I at CfA
have been running a series of workshops on Practical Python for
Astronomers.  The first and most difficult workshop was building a
usable Python installation on individual laptops supporting Mac
(mostly), linux, and Windows.  Once we got the base installation done
with Python, NumPy, SciPy and matplotlib then there were a bunch of
other packages that we use during the workshops.  The instructions for
installing these were:

easy_install asciitable
easy_install http://www.stsci.edu/resources/software_hardware/pyfits/pyfits-2.4.0.tar.gz
easy_install pywcs
easy_install atpy
easy_install aplpy
easy_install http://stsdas.stsci.edu/astrolib/vo-0.6.tar.gz
easy_install http://stsdas.stsci.edu/astrolib/coords-0.37.tar.gz
easy_install pyparsing
easy_install pyregion

For the most part this worked quite well across all the platforms.  So
why can't pyfits, vo, and coords be there on PyPI to supply the
download URL to easy_install in a uniform and non-version-dependent
way?  (The fact that I'm singling out those three should be taken as a
compliment that they are useful and worth the bother).  Of course you
cannot guarantee that this will *always* build properly, but it's
certainly worth an initial try the "easy" way.

If package authors could make their source distribution available via
PyPI would be a nice step toward making Python easier to adopt for
astronomers.  Again I understand there can be complications and
ensuring perfection is impossible, but sometimes better is the enemy
of good.

- Tom