BAIJ and AIJ formats

Manav Bhatia bhatiamanav at
Sun Sep 28 14:50:41 CDT 2008

One more question:
When is it advantageous to use BAIJ format instead of AIJ?


On Sep 28, 2008, at 3:48 PM, Manav Bhatia wrote:

> Hi,
>    I have a few questions about the block format matrix.
>     In the function: MatCreateSeqBAIJ, the arguments are
> bs	- size of block
> m	- number of rows
> n	- number of columns
> nz	- number of nonzero blocks per block row (same for all rows)
> nnz	- array containing the number of nonzero blocks in the various  
> block rows (possibly different for each block row) or PETSC_NULL
> If I specify the nnz vector, then what is the dimension of this  
> vector? Is that equal to the block size? If so, then is it assumed  
> that all blocks have the same number of non-zeros per row?
> If my blocks have different non-zero patterns, then should I use an  
> AIJ format instead of a BAIJ format?
> Thanks,
> Manav

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the petsc-users mailing list