<div class="gmail_quote">On Wed, Apr 25, 2012 at 06:25, Jed Brown <span dir="ltr"><<a href="mailto:jedbrown@mcs.anl.gov">jedbrown@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>Run with -ksp_monitor_true_residual -ksp_converged_reason -snes_monitor -snes_converged_reason -snes_ls_monitor -snes_view and send the output.</div><div><br></div><div>Your SNES callback gets two Mat arguments, into which are you assembling your approximate Jacobian? Are you still calling MatAssemblyBegin/End on the first argument, as in the examples?</div>
</blockquote></div><br><div>There are plenty of additional suggestions here</div><div><br></div><div><a href="http://scicomp.stackexchange.com/questions/30/why-is-newtons-method-not-converging">http://scicomp.stackexchange.com/questions/30/why-is-newtons-method-not-converging</a></div>