Re: Q: Exponential or inversion of sparse matrices
- To: mathgroup at christensen.cybernetics.net
- Subject: [mg1929] Re: Q: Exponential or inversion of sparse matrices
- From: galand at cephag.observ-gr.fr (Marina Galand)
- Date: Wed, 23 Aug 1995 22:31:20 -0400
I am looking for a mathematica fortran or C library corresponding
to my problem, that is concerning operations on sparse matrices.
I need help on the calculation of the exponential
of sparse matrices or at least on the inversion of sparse
matrices. I am looking for fortran or C library dealing with
sparse matrices and that computes the exponential or the inversion.
Recently I developed a method calculate the exponential
of a sparse matrix. I wrote it in a m-file under Matlab.
Now that I have validated it under Matlab, I would like to
use it on hudge sparse matrix. Matlab is not adapted to this,
being much too slow and restricted for memory. Therefore I want to
translate my m-file into a language which can be compiled
such as C or Fortran. The problem is that my algorithm performs
the inversion of a sparse matrix and I do not find a routine
in a fortran or C library to invert a sparse matrix.
In the libraries for sparse matrices I have just found routines
for the solution of a linear system :
routine resolving a linear system A.bj=cj, vector bj being the unknown
and c being a vector of zeros except at row j. Then the result bj
represents the column j of A^(-1). But you must apply the routine
a large number of times, the number of column of A... Is it realistic ?
I will be very pleased if you could answer me and help me
on this subject. Your advice will be welcome.
> > *---------------------------------------------------------------------------*
> > * Marina Galand | *
> > * CEPHAG - ENSIEG | Tel (33) 76 82 62 66 *
> > * Rue de la Houille Blanche - BP 46 | *
> > * 38402 Saint Martin d'Heres Cedex | Fax (33) 76 82 63 84 *
> > * FRANCE | *
> > *---------------------------------------------------------------------------*
> >
>
--
*---------------------------------------------------------------------------*
* Marina Galand | *
* CEPHAG - ENSIEG | Tel (33) 76 82 62 66 *
* Rue de la Houille Blanche - BP 46 | *
* 38402 Saint Martin d'Heres Cedex | Fax (33) 76 82 63 84 *
* FRANCE | *
*---------------------------------------------------------------------------*