<div class="gmail_quote">On Sat, Aug 27, 2011 at 12:22, Milan Mitrovic <span dir="ltr"><<a href="mailto:milan.v.mitrovic@gmail.com">milan.v.mitrovic@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
[1]PETSC ERROR: Unknown Mat type given: same!</blockquote></div><br><div>What kind of Mat were you assembling? Are you passing any other flags? What does your code assemble for the Jacobian? I think the Jacobian you passed in does not implement MatDuplicate(). I just changed MatConvert() to be more robust in petsc-dev.</div>
<div><br></div><div>With 3.1, you can try -pc_type lu -snes_monitor -ksp_monitor_singular_value. Also compare output with -snes_mf_operator. I think your Jacobian may be singular and this should help figure that out.</div>