<div class="gmail_quote">On Mon, Aug 8, 2011 at 17:16, 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="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div id=":10o">Add a KSP/SNES./TSSetDirichlet(ksp,snes,ts,IS listofnodes,Vec valuesfornodes)?</div></blockquote></div><br><div>This might be worthwhile. It needs a new Mat primitive which zeros the rows and columns while also "remembering" the column values that it zeroed (as another assembled matrix). I think it's best to apply the transformation immediately after residuals are calculated so that norms are correct (not in KSP at all). Matrix values are not available at this time so the Dirichlet equations may not be scaled correctly for GMG. We have to be careful that the residual evaluation passed to MatMFFD has the Dirichlet projection inside it.</div>