[SciPy-dev] Ideas for scipy.sparse?

[Robert Kern]

On Fri, Apr 11, 2008 at 12:47 PM, Brian Granger <ellisonbg.net at gmail.com> wrote:
>  2) I need these things to be in numpy.  I hate to start another
>  "should this go into numpy or scipy" thread, but I actually do think
>  there is a decent case for moving the core sparse arrays into numpy
>  (not the solvers though).  Please hear me out:
>
>  a) Numpy at its core is about arrays.  Conceptually, sparse arrays fit
>  into this narrow vision of Numpy.

Previously, Travis has stated a desire to get some form of standard
sparse array (or possibly just matrix) support into numpy 1.1 for
precisely this reason. I happen to agree. However, I have to address
the following points.

>  b) Sparse arrays are just as foundational as dense arrays in many
>  areas of computing/science (I would argue, that they are more
>  foundational than ffts and random numbers).

The parenthetical is not a relevant argument.
numpy.{linalg,fft,random} exist because of history, not design. In
order to convince people to move from Numeric to numpy, we *had* to
support a transition from the LinearAlgebra, FFT, and RandomArray
modules that were distributed with Numeric.

>  d) It would not make numpy more difficult to build.

A fair amount of the current sparse code uses C++ templates, so I will
have to say that this statement needs qualification. The impact may be
low, but it is not negligible. If we rewrite it not to use C++, then
we don't know how much more difficult it will be. We will need to
evaluate that when the code is written. The only thing that we can be
sure won't make numpy more difficult to build is pure Python code.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless
enigma that is made terrible by our own mad attempt to interpret it as
though it had an underlying truth."
 -- Umberto Eco