Preallocating Matrix

[Satish Balay]

Not sure what you mean by "numbers of zero per row"

Do you mean "number of zeros per row" or "column indices of zeros for
each row"?. Either way - you should be able to write a single loop
over this thingy - to compute the required nnz[]

Satish

On Thu, 23 Apr 2009, Andreas Grassl wrote:

> Hello,
> 
> I'm assembling large matrices giving just the numbers of zero per row and
> wondering if it is possible to extract the nonzero-structure in array-format it
> can be fed again into
> 
> MatSeqAIJSetPreallocation(Mat B,PetscInt nz,const PetscInt nnz[])
> 
> to detect the bottleneck?
> 
> cheers
> 
> ando
> 
>