<div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On Thu, Feb 2, 2017 at 1:25 PM, Austin Herrema <span dir="ltr"><<a href="mailto:aherrema@iastate.edu" target="_blank">aherrema@iastate.edu</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">Hello all,<div><br></div><div>I'm having a strange issue when using the MatSetVals function in Fortran. The code is quite large, but relevant snippets of what I'm trying to do are below.<br><br clear="all"><div><div><font color="#666666"> ! PETSc variable declaration</font></div><div><font color="#666666"> Mat LHS</font></div><div><font color="#666666"> PetscErrorCode ier</font></div><div><font color="#666666"> PetscInt idx1(nsd*nsd*nshl*nshl), idx2(nsd*nsd*nshl*nshl)</font></div><div><font color="#666666"> PetscScalar vals(nsd*nsd*nshl*nshl)</font></div></div></div></div></blockquote><div><br></div><div>vals should be of size nidx1 * nidx2.</div><div><br></div><div> Matt</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div><div><div><br> <font color="#666666">! Code for filling in index and value arrays... I've verified that there are 2304 elements in each array.</font><br><br><font color="#666666"> ! Fill in values<br> call MatSetValues(LHS, nvals, idx1, nvals, idx2, vals, ADD_VALUES, ier)</font><br></div><br>Upon executing this, I get a general segmentation violation error. Running in Valgrind I get:<br><br><div><font color="#666666">==87676== Invalid read of size 8</font></div><div><font color="#666666">==87676== at 0x1008D1F45: MatSetValues_SeqAIJ (aij.c:461)</font></div><div><font color="#666666">==87676== by 0x1004C523C: MatSetValues (matrix.c:1190)</font></div><div><font color="#666666">==87676== by 0x10053F1A5: matsetvalues_ (matrixf.c:696)</font></div><div><font color="#666666">==87676== by 0x10005F47D: petsc_fillmat_ (petsc_fillMat.F90:78)</font></div><div><font color="#666666">==87676== by 0x10005E5C9: intelmass_shell_ (shell_IntElmAss.F90:330)</font></div><div><font color="#666666">==87676== by 0x100057259: solflowgmres_ (solflow.F90:125)</font></div><div><font color="#666666">==87676== by 0x100051051: MAIN__ (driver.F90:140)</font></div><div><font color="#666666">==87676== by 0x1000545C4: main (driver.F90:7)</font></div><div><font color="#666666">==87676== Address 0x10a4dac60 is 0 bytes after a block of size 18,432 alloc'd</font></div><div><font color="#666666">==87676== at 0x100088681: malloc (in /usr/local/Cellar/valgrind/3.<wbr>12.0/lib/valgrind/vgpreload_<wbr>memcheck-amd64-darwin.so)</font></div><div><font color="#666666">==87676== by 0x10005EF47: petsc_fillmat_ (petsc_fillMat.F90:23)</font></div><div><font color="#666666">==87676== by 0x10005E5C9: intelmass_shell_ (shell_IntElmAss.F90:330)</font></div><div><font color="#666666">==87676== by 0x100057259: solflowgmres_ (solflow.F90:125)</font></div><div><font color="#666666">==87676== by 0x100051051: MAIN__ (driver.F90:140)</font></div><div><font color="#666666">==87676== by 0x1000545C4: main (driver.F90:7)</font></div><div><font color="#666666">==87676==</font></div><div><font color="#666666">==87676== Conditional jump or move depends on uninitialised value(s)</font></div><div><font color="#666666">==87676== at 0x1008D1F57: MatSetValues_SeqAIJ (aij.c:463)</font></div><div><font color="#666666">==87676== by 0x1004C523C: MatSetValues (matrix.c:1190)</font></div><div><font color="#666666">==87676== by 0x10053F1A5: matsetvalues_ (matrixf.c:696)</font></div><div><font color="#666666">==87676== by 0x10005F47D: petsc_fillmat_ (petsc_fillMat.F90:78)</font></div><div><font color="#666666">==87676== by 0x10005E5C9: intelmass_shell_ (shell_IntElmAss.F90:330)</font></div><div><font color="#666666">==87676== by 0x100057259: solflowgmres_ (solflow.F90:125)</font></div><div><font color="#666666">==87676== by 0x100051051: MAIN__ (driver.F90:140)</font></div><div><font color="#666666">==87676== by 0x1000545C4: main (driver.F90:7)</font></div><div><font color="#666666">==87676==</font></div><div><font color="#666666">==87676== Conditional jump or move depends on uninitialised value(s)</font></div><div><font color="#666666">==87676== at 0x1008D1F62: MatSetValues_SeqAIJ (aij.c:463)</font></div><div><font color="#666666">==87676== by 0x1004C523C: MatSetValues (matrix.c:1190)</font></div><div><font color="#666666">==87676== by 0x10053F1A5: matsetvalues_ (matrixf.c:696)</font></div><div><font color="#666666">==87676== by 0x10005F47D: petsc_fillmat_ (petsc_fillMat.F90:78)</font></div><div><font color="#666666">==87676== by 0x10005E5C9: intelmass_shell_ (shell_IntElmAss.F90:330)</font></div><div><font color="#666666">==87676== by 0x100057259: solflowgmres_ (solflow.F90:125)</font></div><div><font color="#666666">==87676== by 0x100051051: MAIN__ (driver.F90:140)</font></div><div><font color="#666666">==87676== by 0x1000545C4: main (driver.F90:7)</font></div><div><font color="#666666">==87676==</font></div><br><font color="#000000">I'm not terribly experienced with Valgrind but I can't find anything too helpful in that output. It shows the traceback but I still cannot understand <i>why </i>the error is being produced. Strangely, if I try to set the matrix values in a few smaller chunks, i.e.<br></font><br><div><font color="#666666"> call MatSetValues(LHS, 500, idx1(1:500), 500, idx2(1:500), vals(1:500), ADD_VALUES, ier)</font></div><div><font color="#666666"> call MatSetValues(LHS, 500, idx1(501:1000), 500, idx2(501:1000), vals(501:1000), ADD_VALUES, ier)</font></div><div><font color="#666666"> call MatSetValues(LHS, 500, idx1(1001:1500), 500, idx2(1001:1500), vals(1001:1500), ADD_VALUES, ier)</font></div><div><font color="#666666"> call MatSetValues(LHS, 500, idx1(1501:2000), 500, idx2(1501:2000), vals(1501:2000), ADD_VALUES, ier)</font></div><div><font color="#666666"> call MatSetValues(LHS, 304, idx1(2001:2304), 304, idx2(2001:2304), vals(2001:2304), ADD_VALUES, ier)</font></div><br></div><div><font color="#000000">Then everything works with no errors. Is there some kind of limitation to how many values you can insert into a matrix at once? Would strike me as strange. I can assign elements one at a time but reducing the number of calls to MatSetVals by a factor of 2000 would be fantastic. I would be happy to provide more details of the matrix setup if necessary.<br><br>Thank you for any help!<span class="HOEnZb"><font color="#888888"><br>Austin</font></span></font></div><span class="HOEnZb"><font color="#888888"><div><br></div><div><br></div>-- <br><div class="m_3032578857177953867gmail_signature"><div dir="ltr"><div dir="ltr" style="color:rgb(136,136,136);font-size:12.8px"><b style="font-size:12.8px"><font color="#666666">Austin Herrema</font></b><br></div><div dir="ltr" style="color:rgb(136,136,136);font-size:12.8px"><div><font color="#999999">PhD Student | Graduate Research Assistant | Iowa State University</font></div><div><font color="#999999">Wind Energy Science, Engineering, and Policy | Mechanical Engineering</font></div></div></div></div></font></span></div></div>
</blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature" data-smartmail="gmail_signature">What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.<br>-- Norbert Wiener</div>
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