Sparse Matrix Inversion using PETSc

[Dr. Timothy Stitt]

Firstly, many thanks to everyone who has replied with information. It 
has been very useful indeed. Much appreciated.

Barry, in this case the sparse matrices would be of ~ order 5000x5000. 
They could grow in size but this is the sample matrices I am working 
with right now. We would love a scalable approach so we can deal with 
more interesting problems and hence larger sparse matrices. Hope that helps.

Many thanks again.

Tim.

Barry Smith wrote:
>   Tim,
>
>     How large are you matrices?
>
>    Barry
>
>
> On Wed, 15 Aug 2007, Dr. Timothy Stitt wrote:
>
>   
>> Hi all,
>>
>> I am currently investigating the best way to perform the inversion of a large
>> sparse matrix and came upon the idea of using PETSc as a framework for testing
>> various strategies from direct to iterative methods on my sample matrices. In
>> this setup for an NxN sparse matrix A I would have N rhs's representing the
>> Identity matrix and then solve for X. I wanted to experiment with both
>> parallel and serial strategies ranging from LU Decomposition using SuperLU,
>> MUMPS etc. to iterative methods using GMRES etc. Am I right in thinking that
>> all this can be done in PETSc by setting up a core framework and then varying
>> the solver methods etc?
>>
>> I have looked over the sample KSP Solver codes although they only seem to
>> suggest single vectors for x and b. Can this be changed to accept multiple
>> vectors? Can anyone suggest a sample code that maybe demonstrates the sort of
>> thing I want to achieve...if it is in fact possible.
>>
>> Thanks in advance for any assistance given,
>>
>> Regards,
>>
>> Tim.
>>
>>
>>     
>
>