<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>On Feb 15, 2012, at 11:19 AM, Hui Zhang wrote:</div><div><br class="Apple-interchange-newline"><blockquote type="cite"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Hi Dmitry,<div><br></div><div>thanks a lot! Currently, I'm not using ISColoring. Just comes another question</div><div>on PCGASMSetModifySubMatrices(). The user provided function has the prototype</div><div><br></div><div><span class="Apple-style-span" style="font-family: monospace; white-space: pre; "> func (</span><span class="Apple-style-span" style="font-family: monospace; white-space: pre; "><a href="file:///Users/huizhang/Documents/petsc/docs/manualpages/PC/PC.html#PC">PC</a></span><span class="Apple-style-span" style="font-family: monospace; white-space: pre; "> pc,</span><span class="Apple-style-span" style="font-family: monospace; white-space: pre; "><a href="file:///Users/huizhang/Documents/petsc/docs/manualpages/Sys/PetscInt.html#PetscInt">PetscInt</a></span><span class="Apple-style-span" style="font-family: monospace; white-space: pre; "> nsub,</span><span class="Apple-style-span" style="font-family: monospace; white-space: pre; "><a href="file:///Users/huizhang/Documents/petsc/docs/manualpages/IS/IS.html#IS">IS</a></span><span class="Apple-style-span" style="font-family: monospace; white-space: pre; "> *row,</span><span class="Apple-style-span" style="font-family: monospace; white-space: pre; "><a href="file:///Users/huizhang/Documents/petsc/docs/manualpages/IS/IS.html#IS">IS</a></span><span class="Apple-style-span" style="font-family: monospace; white-space: pre; "> *col,</span><span class="Apple-style-span" style="font-family: monospace; white-space: pre; "><a href="file:///Users/huizhang/Documents/petsc/docs/manualpages/Mat/Mat.html#Mat">Mat</a></span><span class="Apple-style-span" style="font-family: monospace; white-space: pre; "> *submat,void *ctx);</span></div><div><span class="Apple-style-span" style="font-family: monospace; white-space: pre; "><br></span></div><div><span class="Apple-style-span" style="white-space: pre; ">I think the coloumns from the parameter 'col' are always the same <font class="Apple-style-span" face="monospace">as the rows </font></span></div><div><span class="Apple-style-span" style="white-space: pre; "><font class="Apple-style-span" face="monospace">from the parameter 'row'. Because PCGASMSetLocalSubdomains() only accepts </font></span></div><div><span class="Apple-style-span" style="white-space: pre; "><font class="Apple-style-span" face="monospace">index sets but not rows and columns. Has I misunderstood something?</font></span></div></div></blockquote><div><br></div><div>As I tested, the row and col are always the same. </div><div><br></div><div>I have a new question. Am I allowed to SetLocalToGlobalMapping() for the submat's</div><div>in the above func()?</div><div><br></div><div>thanks,</div><div>Hui</div><br><blockquote type="cite"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><span class="Apple-style-span" style="white-space: pre; "><font class="Apple-style-span" face="monospace"><br></font></span></div><div><span class="Apple-style-span" style="white-space: pre; "><font class="Apple-style-span" face="monospace">thanks,</font></span></div><div><span class="Apple-style-span" style="white-space: pre; "><font class="Apple-style-span" face="monospace">Hui</font></span></div><div><br></div><div><br><div><div>On Feb 11, 2012, at 3:36 PM, Dmitry Karpeev wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">Yes, that's right.<div>There is no good way to help the user assemble the subdomains at the moment beyond the 2D stuff.</div><div>It is expected that they are generated from mesh subdomains.</div><div>Each IS does carry the subdomains subcomm.</div>
<div><br></div><div>There is ISColoringToList() that is supposed to convert a "coloring" of indices to an array of ISs,</div><div>each having the indices with the same color and the subcomm that supports that color. It is</div>
<div>largely untested, though. You could try using it and give us feedback on any problems you encounter.</div><div><br></div><div>Dmitry.</div><div><br><br><div class="gmail_quote">On Sat, Feb 11, 2012 at 6:06 AM, Hui Zhang <span dir="ltr"><<a href="mailto:mike.hui.zhang@hotmail.com">mike.hui.zhang@hotmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">About PCGASMSetLocalSubdomains(), in the case of one subdomain supported by<br>
multiple processors, shall I always create the arguments 'is[s]' and 'is_local[s]'<br>
in a subcommunicator consisting of processors supporting the subdomain 's'?<br>
<br>
The source code of PCGASMCreateSubdomains2D() seemingly does so.<br>
<br>
Thanks,<br>
Hui<br>
<br>
</blockquote></div><br></div>
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