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</o:shapelayout></xml><![endif]--></head><body lang=DE link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Thanks a lot, without you I would sit for my code until midnight<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>Von:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> petsc-users-bounces@mcs.anl.gov [mailto:petsc-users-bounces@mcs.anl.gov] <b>Im Auftrag von </b>Jed Brown<br><b>Gesendet:</b> Freitag, 20. Mai 2011 13:33<br><b>An:</b> PETSc users list<br><b>Betreff:</b> Re: [petsc-users] creating csr matrix from 3 arrays<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>2011/5/20 Dürrwang, Jürgen <<a href="mailto:Juergen.Duerrwang@iosb.fraunhofer.de">Juergen.Duerrwang@iosb.fraunhofer.de</a>><o:p></o:p></p><p class=MsoNormal><span lang=EN-US>MatSetValues(A,n,prow,nz,pcol,pval,INSERT_VALUES);</span><o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>This function inserts logically dense blocks. You would loop over rows:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>for (row=0; row<n; row++) {<o:p></o:p></p></div><div><p class=MsoNormal> PetscInt ncol = prow[row+1] - prow[row];<o:p></o:p></p></div><div><p class=MsoNormal> PetscInt offset = prow[row];<o:p></o:p></p></div><div><p class=MsoNormal> MatSetValues(A,1,&row,ncol,&pcol[offset],&pval[offset],INSERT_VALUES);<o:p></o:p></p></div><div><p class=MsoNormal>}<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>You should preallocate if at all possible. If your format is exactly as described here and you want the matrix to use your memory, look at:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><a href="http://www.mcs.anl.gov/petsc/petsc-as/snapshots/petsc-dev/docs/manualpages/Mat/MatCreateSeqAIJWithArrays.html">http://www.mcs.anl.gov/petsc/petsc-as/snapshots/petsc-dev/docs/manualpages/Mat/MatCreateSeqAIJWithArrays.html</a><o:p></o:p></p></div></div></body></html>