[SciPy-user] Sparse factorisation

[Gael Varoquaux]

On Fri, May 01, 2009 at 10:17:29AM +0200, Gael Varoquaux wrote:
> In the mean time, I figured out that I only needed to expose thee
> permutation vectors from the factored_lu object. These permutation vector
> are not sparse objects, so it is very easy to expose them to numpy (just
> a question of PyArray_SimpleNewFromData and using the 'base' trick (
> http://blog.enthought.com/?p=62 ) to do the reference counting. 

> This is a bit ugly, because it does not expose all the information.
> Another issue is that as long as there are references on the arrays
> created as views from the permutation vectors, the whole factored_lu
> object (much heavier in memory) is not garbaged collecter.

> If we can live with these limitations, I think I can contribute a clean
> patch. It does not solve completely my problem, but still does one step
> in the right direction.

I attached a patch implementing the above plan. It is up for review.

http://projects.scipy.org/scipy/ticket/937

Gaël