[Insight-users] solving large linear equations

[Arnaud Gelas]

Hi habbib,

How large is your matrix?
How sparse is your matrix? Do you know the number of non null elements 
in your matrix? Or can you tell me the number of non null elements per 
row (in average)?

Solving sparse linear system highly depends on the sparsity of your matrix.
When you say I am "using VNL sparse system solver", what do you mean? 
which class are you using?

Note that it is not because you use BLAS and LAPACK that the code will 
be fast, it depends how they are used in in the library. For example 
mumps, taucs are also based on blas and lapack and performances are 
really different...

Arnaud

Habib Baluwala wrote:
> Hi everyone , 
>                  I am currently using a large sparse system of linear
> equation which is non-symmetric. I tried using VNL sparse system solvers but
> they are very slow , I can't still understand why they are slow because they
> are supposed to utilise the BLAS and Lapack libraries to speed up. Can
> anyone tell me how can I speed up the procedure???? I also tried the release
> instead of debug. It was able to reduce the time taken but not to a
> significant effect. Would including the Utilities folder in the
> CMakeFile.txt help ???
>
> I look forward to your reply and sorry for any inconvenience. 
>
>
>
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