thank you very much, Barry<br><br><div class="gmail_quote">On Thu, Jan 1, 2009 at 4:59 PM, Barry Smith <span dir="ltr"><<a href="mailto:bsmith@mcs.anl.gov">bsmith@mcs.anl.gov</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
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For all Mats that PETSc provides including MatMFFD and MatShell() the assumption is satisfied.<br><font color="#888888">
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Barry</font><div><div></div><div class="Wj3C7c"><br>
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On Jan 1, 2009, at 6:45 PM, Yujie wrote:<br>
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<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
I got a submatrix B from A in parallel mode. Because the rows numbers of B in some processors of the cluster become 0, I want to use MatGetOwnershipRange() to get the range in each processor. I have checked this function, the description is as folllows:<br>
"<br>
MatGetOwnershipRange<br>
Returns the range of matrix rows owned by this processor, assuming that the matrix is laid out with the first n1 rows on the first processor, the next n2 rows on the second, etc. For certain parallel layouts this range may not be well defined.<br>
"<br>
There is an assumption in this function, I am wondering whether I can use this function here. if not, how to do it? thanks a lot.<br>
<br>
Yujie<br>
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