<div dir="ltr"><div dir="ltr">On Sat, Dec 11, 2021 at 1:58 PM Tang, Qi <<a href="mailto:tangqi@msu.edu">tangqi@msu.edu</a>> wrote:<br></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">



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<div>Hi,</div>
<div>Does anyone have comment on finite difference coloring with DMStag? We are using DMStag and TS to evolve some nonlinear equations implicitly. It would be helpful to have the coloring Jacobian option with that.</div></div></div></blockquote><div><br></div><div>Since DMStag produces the Jacobian connectivity, you can use -snes_fd_color_use_mat. It has many options. Here is an example of us using that:</div><div><br></div><div>  <a href="https://gitlab.com/petsc/petsc/-/blob/main/src/snes/tutorials/ex19.c#L898">https://gitlab.com/petsc/petsc/-/blob/main/src/snes/tutorials/ex19.c#L898</a></div><div><br></div><div>  Thanks,</div><div><br></div><div>     Matt</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div style="overflow-wrap: break-word;"><div>
<div>Thanks,</div>
<div>Qi</div>
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<div>On Oct 15, 2021, at 3:07 PM, Jorti, Zakariae via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov" target="_blank">petsc-users@mcs.anl.gov</a>> wrote:</div>
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<div style="margin-top:0px;margin-bottom:0px">Hello,</div>
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<div style="margin-top:0px;margin-bottom:0px">Does the Jacobian approximation <span style="font-size:12pt">using coloring and finite differencing of the function evaluation work in DMStag? </span><span style="font-size:12pt">  </span></div>
<div style="margin-top:0px;margin-bottom:0px">Thank you.</div>
<div style="margin-top:0px;margin-bottom:0px">Best regards,</div>
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<div style="margin-top:0px;margin-bottom:0px">Zakariae </div>
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</blockquote></div><br clear="all"><div><br></div>-- <br><div dir="ltr" class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div>What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.<br>-- Norbert Wiener</div><div><br></div><div><a href="http://www.cse.buffalo.edu/~knepley/" target="_blank">https://www.cse.buffalo.edu/~knepley/</a><br></div></div></div></div></div></div></div></div>