<div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On Mon, Jan 13, 2014 at 2:27 PM, Rémi Lacroix <span dir="ltr"><<a href="mailto:remi.lacroix@inria.fr" target="_blank">remi.lacroix@inria.fr</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div text="#000000" bgcolor="#FFFFFF">
<div>Le 13/01/2014 19:00, Matthew Knepley a
écrit :<br>
</div>
<blockquote type="cite">
<div dir="ltr">
<div class="gmail_extra">
<div class="gmail_quote">On Mon, Jan 13, 2014 at 9:47 AM, Rémi
Lacroix <span dir="ltr"><<a href="mailto:remi.lacroix@inria.fr" target="_blank">remi.lacroix@inria.fr</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hello,<br>
<br>
I would like to permute an index set with another index
set, just like you can do for vectors using VecScatter.<br>
<br>
I have two index sets IS1 and IS2 which share the same
size but have different parallel layouts. I often need to
permute vectors/matrices using those two index sets (as in
first permute with IS1 then permute the result with IS2).
Since I don't use the intermediate result, I would like to
permute IS1 with IS2 to get a new index set so that I can
permute directly my vectors/matrices with it. Is that
possible using Petsc?<br>
</blockquote>
<div><br>
</div>
<div>We do not have this particular composition in our
interface. However, you could accomplish this using
PetscSF.</div>
<div><br>
</div>
<div> Thanks,
<div><br>
</div>
<div> Matt</div>
</div>
</div>
</div>
</div>
</blockquote>
<br>
Thanks for the quick answer.<br>
<br>
So basically I need to have a look at the underlying mechanism of
VecScatter and implement something similar for IS. How complex would
it be in practice?</div></blockquote><div><br></div><div>Using the PetscSF interface instead of VecScatter should not be too hard.</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 text="#000000" bgcolor="#FFFFFF"><span class="HOEnZb"><font color="#888888"><br>
Rémi<br>
</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
</div></div>