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<p class=MsoNormal>Hello,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I have a rather simple question. For a Matrix that was
preallocated with the correct diagonal and offdiagonal nonzero counts the
following operations cause a deallocation of all data except the diagonal which
casues later MatSetValues to have to reallocate.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>MatCreateSeqAIJ<o:p></o:p></p>
<p class=MsoNormal>MatZeroEntries<o:p></o:p></p>
<p class=MsoNormal>MatDiagaonalSet<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Using -info and the debugger I see that MatDiagonalSet ends
up calling MatDiagonalSet_Default which forces an assembly. Is there a way to
do the same thing and preserve the preallocated storage for future use by
MatSetValues? I tried MatSetOption with MAT_KEEP_ZEROED_ROWS and
MAT_IGNORE_ZERO_ENTRIED but it did not help.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thanks a lot,<o:p></o:p></p>
<p class=MsoNormal>Harun<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
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