<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; ">Hi, <DIV><BR class="khtml-block-placeholder"></DIV><DIV> I am performing a matrix multiplication of two dense matrices with both MatMatMult and MatMatMultTranspose. </DIV><DIV> What do I choose a fill factor as? According to the definition in the documentation: fiill = <FONT class="Apple-style-span" face="Times" size="4"><SPAN class="Apple-style-span" style="font-size: 13.3px;">expected fill as ratio of nnz(C)/(nnz(A) + nnz(B)). </SPAN></FONT></DIV><DIV> So, If I have two full matrices A and B, I will get a full matrix as my result. Hence, the fill factor will be 0.5. However, both these methods give an error with a fill factor less than 1.0. Also, if I use PETSC_DFAULT as the fill argument, it agains results in an error since its value is -2.</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Kindly help me with your advice here.</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Thanks</DIV><DIV>Manav</DIV></BODY></HTML>