[petsc-dev] Dense matrices

Jed Brown jed at 59A2.org
Sun Jan 17 10:42:24 CST 2010

On Fri, 15 Jan 2010 09:58:46 -0600, Matthew Knepley <knepley at gmail.com> wrote:
> SeqDense MatMult was inexplicably giving me the wrong answers. I
> checked the BLAS call (and the underlying defines) and they also
> looked right to me. I temporarily checked in the simple-minded loops
> which do give me the correct answer.

The matrices are column-aligned.  The "simple-minded loops" you checked
in (cc0b86d7fd3f) assume row-aligned matrices, and are thus delivering
the wrong results for everyone that assembled their matrix correctly, so
I'm reverting that change.

How were you assembling this matrix?


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