[SciPy-dev] feedback on scipy.sparse

[Stefan van der Walt]

On Thu, Dec 13, 2007 at 01:17:22PM -0600, Nathan Bell wrote:
> > Concerning the Stefan's idea of static methods for spidentity etc., we
> > could use only one method for all of them, e.g.
> >
> > class spmatrix:
> >
> >      def special( name, format = ... ):
> >         if name = 'identity':
> >              return spidentity(n,format=format)
> >          ...
> >
> > to prevent cluttering od the class you mentioned.
> 
> Good idea, I hadn't considered that option.

If we do this, we are still merging functionality belonging in
different classes together.  Say we'd like to refactor lil_matrix into
another package, for some reason.  If we use "special", then
extracting the functionality pertaining only to lil_matrix becomes a
problem.  I think functionality that requires insight into the
entrails of an object belongs with that object.

Furthermore,

LilMatrix.special('eye',(3,4)) looks very verbose, compared to

LilMatrix.eye([3,4])

How many of these functions do we have?  If we have in the order of 5
to 10, then cluttering isn't really a problem.

Also, not all of these function need to be re-implemented from
spmatrix (can we rename this to SparseMatrix for consistency?).  For
example, LilMatrix inherits .eye, which can simply defined in terms
of .diag.

Regards
Stéfan