<p>There is not a PETSc function to set Dirichlet conditions. There are many ways to do it, you should pick a way they works well for your problem.</p>
<p>I think you might misunderstand KSPSetNullSpace.</p>
<div class="gmail_quote">On Dec 5, 2011 6:59 PM, "Hailong Xiao" <<a href="mailto:xiaohl1986@gmail.com">xiaohl1986@gmail.com</a>> wrote:<br type="attribution"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div class="gmail_quote">Hi<div><br></div><div>I am solving an elliptic problem with Neumann boundary condition with dmda routines by snes solver.</div><div>I set up the residue by DMDASetLocalFunction.</div><div>Besides the way like fix the first value to be one by myself, is there way to do it by petsc routine? like the <span style="font-family:Simsun;background-color:rgb(213,234,255);font-size:medium">KSPSetNullSpace() rountine does?</span></div>
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<div><br clear="all"><div><span style="color:rgb(0,0,0)">-- </span></div></div></font></span></div>Hailong<br>
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