On Thu, Feb 23, 2012 at 12:05 PM, Bojan Niceno <span dir="ltr"><<a href="mailto:bojan.niceno@psi.ch">bojan.niceno@psi.ch</a>></span> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000">
Dear Matthew,<br>
<br>
<br>
thank you for your response. When I use VecCreateGhost, I get the
following:<br></div></blockquote><div><br></div><div>It appears that you passed a bad communicator. Did you not initialize a 'comm' variable?</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 bgcolor="#FFFFFF" text="#000000">
[0]PETSC ERROR:
------------------------------------------------------------------------<br>
[0]PETSC ERROR: Caught signal number 11 SEGV: Segmentation
Violation, probably memory access out of range<br>
[0]PETSC ERROR: Try option -start_in_debugger or
-on_error_attach_debugger<br>
[0]PETSC ERROR: or see
<a href="http://www.mcs.anl.gov/petsc/petsc-as/documentation/faq.html#valgrind" target="_blank">http://www.mcs.anl.gov/petsc/petsc-as/documentation/faq.html#valgrind</a>[0]PETSC
ERROR: or try <a href="http://valgrind.org" target="_blank">http://valgrind.org</a> on GNU/linux and Apple Mac OS X to
find memory corruption errors<br>
[0]PETSC ERROR: likely location of problem given in stack below<br>
[0]PETSC ERROR: --------------------- Stack Frames
------------------------------------<br>
[0]PETSC ERROR: Note: The EXACT line numbers in the stack are not
available,<br>
[0]PETSC ERROR: INSTEAD the line number of the start of the
function<br>
[0]PETSC ERROR: is given.<br>
[0]PETSC ERROR: [0] PetscCommDuplicate line 140
src/sys/objects/tagm.c<br>
[0]PETSC ERROR: [0] PetscHeaderCreate_Private line 30
src/sys/objects/inherit.c<br>
[0]PETSC ERROR: [0] VecCreate line 32
src/vec/vec/interface/veccreate.c<br>
[0]PETSC ERROR: [0] VecCreateGhostWithArray line 567
src/vec/vec/impls/mpi/pbvec.c<br>
[0]PETSC ERROR: [0] VecCreateGhost line 647
src/vec/vec/impls/mpi/pbvec.c<br>
[0]PETSC ERROR: --------------------- Error Message
------------------------------------<br>
[0]PETSC ERROR: Signal received!<br>
[0]PETSC ERROR:
------------------------------------------------------------------------<br>
[0]PETSC ERROR: Petsc Release Version 3.2.0, Patch 6, Wed Jan 11
09:28:45 CST 2012<br>
[0]PETSC ERROR: See docs/changes/index.html for recent updates.<br>
[0]PETSC ERROR: See docs/faq.html for hints about trouble shooting.<br>
[0]PETSC ERROR: See docs/index.html for manual pages.<br>
[0]PETSC ERROR:
------------------------------------------------------------------------<br>
[0]PETSC ERROR: ./PSI-Flow on a arch-linu named lccfd06 by niceno
Thu Feb 23 19:02:45 2012<br>
[0]PETSC ERROR: Libraries linked from
/homecfd/niceno/PETSc-3.2-p6/arch-linux2-c-debug/lib<br>
[0]PETSC ERROR: Configure run at Fri Feb 10 10:24:13 2012<br>
[0]PETSC ERROR: Configure options<br>
[0]PETSC ERROR:
------------------------------------------------------------------------<br>
[0]PETSC ERROR: User provided function() line 0 in unknown directory
unknown file<br>
<br>
I don't understand what could be causing it. I took very good care
to match the global numbers of ghost cells when calling
VecCreateGhost<br>
<br>
<br>
Kind regards,<br>
<br>
<br>
Bojan<br>
<br>
<br>
On 2/23/2012 5:53 PM, Matthew Knepley wrote:
<blockquote type="cite">On Thu, Feb 23, 2012 at 10:46 AM, Bojan Niceno <span dir="ltr"><<a href="mailto:bojan.niceno@psi.ch" target="_blank">bojan.niceno@psi.ch</a>></span>
wrote:<br>
<div class="gmail_quote">
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Hi all,<br>
<br>
I've never used a mailing list before, so I hope this message
will reach PETSc users and experts and someone might be
willing to help me. I am also novice in PETSc.<br>
<br>
I have developed an unstructured finite volume solver on top
of PETSc libraries. In sequential, it works like a charm.
For the parallel version, I do domain decomposition
externally with Metis, and work out local and global
numberings, as well as communication patterns between
processor. (The latter don't seem to be needed for PETSc,
though.) When I run my program in parallel, it also works,
but I miss values in vectors' ghost points.<br>
<br>
I create vectors with command: VecCreate(PETSC_COMM_WORLD,
&x);<br>
<br>
Is it possible to get the ghost values if a vector is created
like this?<br>
</blockquote>
<div><br>
</div>
<div>I do not understand this question. By definition, "ghost
values" are those not stored in the global vector.</div>
<div> </div>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
I have tried to use VecCreateGhost, but for some reason which
is beyond my comprehension, PETSc goes berserk when it reaches
the command: VecCreateGhost(PETSC_COMM_WORLD, n, PETSC_DECIDE,
nghost, ifrom, &x)<br>
</blockquote>
<div><br>
</div>
<div>I think you can understand that "berserk" tells me
absolutely nothing. Error message? Stack trace? Did you try to
run an</div>
<div>example which uses VecGhost?</div>
<div><br>
</div>
<div> Thanks,</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">
Can anyone help me? Either how to reach ghost values for
vector created by VecCreate, or how to use VecCreateGhost
properly?<br>
<br>
<br>
Kind regards,<br>
<br>
Bojan<br>
</blockquote>
</div>
<br>
<br clear="all"><span class="HOEnZb"><font color="#888888">
<div><br>
</div>
-- <br>
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<br>
</font></span></blockquote><span class="HOEnZb"><font color="#888888">
<br>
<br>
<div>-- <br>
<img src="cid:part1.08030904.09090507@psi.ch" border="0"></div>
</font></span></div>
</blockquote></div><br><br clear="all"><div><br></div>-- <br>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<br>