[SciPy-dev] Sparse BLAS in scipy

[Anand Patil]

> When you had originally mentioned sparse triangular solves, I thought
> you wanted something more lightweight.

Ideally, I did... but this solution is trivial to write & maintain,
and I figured it would waste no floating-point ops and only relatively
few memory and logic ops.

> Are you sure that spsolve doesn't already do what you want?  I would
> imagine that a reasonably smart LU factorization method would do
> little work when given an upper *or* lower triangular system.

I emailed the maintainer of SuperLU just now, and she said she doubted
it would do anything when asked to factorize an upper triangular
system, but didn't comment on a lower triangular system. Is there any
way to get the lu factors out of a factorized_lu object and check?

Anand