[petsc-users] inserting multiple rows together into a matrix

[Jacob Faibussowitsch]

Also if you know that the rows/cols are contiguous (next to each other) in your sparse matrix then it is recommended to use MatSetValuesBlocked as it is more efficient.

Best regards,

Jacob Faibussowitsch
(Jacob Fai - booss - oh - vitch)
Cell: (312) 694-3391

> On Apr 13, 2020, at 10:32 AM, Junchao Zhang <junchao.zhang at gmail.com> wrote:
> 
> Add two rows 2 ,4,  and each row has three nonzeros at column 3, 7, 9
> m=2;
> n=3;
> idxm[] = {2, 4};
> idxn[] = {3, 7, 9};
> v[6]   = {0.1, 0.2, ....};
> MatSetValues(mat, m, idxm, n, idxn,v, INSERT_VALUES);
> 
> --Junchao Zhang
> 
> 
> On Mon, Apr 13, 2020 at 9:59 AM Bin Liu <lbllm2018 at hotmail.com <mailto:lbllm2018 at hotmail.com>> wrote:
> Hi all,
> 
>  
> 
> I know how to insert values in one row into the matrix via routine “MatSetValues”. I understand I logically should be able to insert multiple rows into the matrix with one call of “MatSetValues”. However, I am not sure how to do it. I searched in the PETSc mail list and did not find a relevant question answered before. Could anyone help me and give me a simple example code?
> 
>  
> 
> Regards
> 
> B.
> 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20200413/0ec0e1f3/attachment.html>