[SciPy-dev] the current state and future directions of the sparse solvers

[Ondrej Certik]

On Thu, Apr 10, 2008 at 11:21 AM, Viral Shah
<vshah at interactivesupercomputing.com> wrote:
> Hi Robert,
>
>
>  > Hi Nathan,
>  >
>  > Nathan Bell wrote:
>
> >>> OK, that sounds very good. I am going to study how to start such a
>  >>> scikit and we are going to move our additional solvers we have in
>  >>> sfepy to it (pysparse, soon petsc4py) -- are you ok with that
>  >>> Robert?
>  >>> :) Plus umfpack.  Plus the eigensolvers, like primme, blzpack and
>  >>> others.
>  >
>  > Sure!
>
>  I agree its good to have more solvers. Tim Davis' SuiteSparse has a
>  whole bunch, and they are the most robust direct sparse solvers out
>  there..
>
>
>  >> I just recently saw a talk by some people that work on providing
>  >> abstract interfaces to the solvers in Trilinos:
>  >> http://trilinos.sandia.gov/packages/docs/r8.0/packages/stratimikos/doc/html/index.html
>  >> http://trilinos.sandia.gov/packages/belos/
>  >>
>  >> I have no experience with these, but they may provide some guidance.
>
>  Trilinos is good idea. By itself, its a huge collection. The relevant
>  piece is Amesos for direct solvers. It makes plugging in various
>  sparse direct solvers effortless.  Cholmod for sparse cholesky seems
>  to not exist yet.
>
>  I am wondering how to find out more about the state of iterative
>  solvers in scipy. Trilinos has all the methods and preconditioners.
>  However, it should be possible to write the iterative solvers and
>  preconditioners  completely in .py. For the standard stuff, perhaps
>  compiled libraries could be used for speed, but the flexibility is
>  nice to have.

Look into the sources, that's the best thing. It's quite well
documented in docstrings and info.py files.
And you need to do it anyway, if you want to contribute. :)

>  The last time I had looked, they didn't have support for complex
>  sparse matrices. I don't know if scipy sparse supports complex
>  matrices or not yet. But if you want to solve non-symmetric eigenvalue

It does.

>  problems, you need that..


Ondrej