<div class="gmail_quote">On Mon, Aug 8, 2011 at 14:44, 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 class="im">> How would you use this interface with SNES?<br>
<br>
</div> The user calls this as part the FormJacobian() (in the same way as if they explicitly remove those rows and columns (what Matt likes) in the matrix assembly.</blockquote></div><br><div>But they need access to the right hand side at the same time. It seems too fragile to reach into the SNES and modify the residual vector during Jacobian evaluation.</div>