<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body style="overflow-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;">  <div>   You absolutely should not need to do an assembly after a VecSet. Please post a full reproducer that demonstrates the problem.</div><div><br></div><div>  Barry</div><div><br id="lineBreakAtBeginningOfMessage"><div><br><blockquote type="cite"><div>On Apr 25, 2025, at 1:23 PM, Derek Teaney via petsc-users <petsc-users@mcs.anl.gov> wrote:</div><br class="Apple-interchange-newline"><div><div dir="ltr"><div>Hi, </div><div><br></div><div>I was under the (mistaken) impression that one does not need to due a VecAssemblyBegin etc following a VecSet, e.g. </div><div><br></div><div>      VecSet(dn_local, 0.);<br>      VecAssemblyBegin(dn_local) ;<br>      VecAssemblyEnd(dn_local) ;<br></div><div><br></div><div>Seems to give different results without the Assembly.  </div><div><br></div><div>Thanks for clarifying, </div><div><br></div><div>Derek</div><div><br></div><span class="gmail_signature_prefix">-- </span><br><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><span style="font-family: Helvetica; font-size: 12px;">------------------------------------------------------------------------</span><br style="font-family: Helvetica; font-size: 12px;"><span style="font-family:Helvetica;font-size:12px"><font>Derek Teaney</font></span><div><font>Professor and Graduate Program Director<br style="font-family:Helvetica;font-size:12px"><span style="font-family:Helvetica;font-size:12px">Dept. of Physics & Astronomy</span><br style="font-family:Helvetica;font-size:12px"><span style="font-family:Helvetica;font-size:12px">Stony Brook University</span><br style="font-family:Helvetica;font-size:12px"><span style="font-family:Helvetica;font-size:12px">Stony Brook, NY 11794-3800</span><br style="font-family:Helvetica;font-size:12px"><span style="font-family:Helvetica;font-size:12px">Tel: (631) 632-4489</span><br style="font-family:Helvetica;font-size:12px"><span style="font-family:Helvetica;font-size:12px">Fax: (631) 632-9718</span></font><br style="font-family: Helvetica; font-size: 12px;"><span style="font-family: Helvetica; font-size: 12px;">e-mail: <a href="mailto:Derek.Teaney@stonybrook.edu" target="_blank">Derek.Teaney@stonybrook.edu</a></span><br style="font-family: Helvetica; font-size: 12px;"><span style="font-family: Helvetica; font-size: 12px;">------------------------------------------------------------------------</span><br style="font-family: Helvetica; font-size: 12px;"><div><span style="font-family: Helvetica; font-size: 12px;"><br></span></div></div></div></div></div>
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