[petsc-users] question about MatMatMult

[Michael Povolotskyi]

On 07/02/2013 01:41 PM, Matthew Knepley wrote:
> On Tue, Jul 2, 2013 at 12:19 PM, Michael Povolotskyi 
> <mpovolot at purdue.edu <mailto:mpovolot at purdue.edu>> wrote:
>
>     On 07/02/2013 12:46 PM, Hong Zhang wrote:
>>     Michael :
>>
>>         Dear Petsc developers,
>>         I'm gradually moving from the version 3.2 to the version 3.4.
>>         I had to skip the version 3.3 because of the bug in
>>         MatMatMult that has been reported to you.
>>
>>         What I see is that the MatMatMult works well but there is a
>>         difference:
>>         in the version 3.2 if a sparse matrix was multiplied by a
>>         dense matrix the result was dense.
>>         In the version 3.4 the result is sparse.
>>
>>
>>      A sparse matrix multiplied by a dense matrix results in a dense
>>     matrix for all petsc versions.
>>     What makes you conclude "In the version 3.4 the result is sparse"?
>>
>>     Hong
>>
>>
>>
>>
>     I use MatMatMult with MAT_INITIAL_MATRIX
>     Then I call MatGetType(A, &type) for the product matrix
>     Then I have an if statement:
>     if (string(type) == "seqdense" || string(type) == "mpidense")
>
>
> What is the type? M->hdr.type_name
>
>    Matt
Looks like everything is fine, I could not reproduce the error any more.
Michael.
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20130703/7b760248/attachment-0001.html>