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Hi all,
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<div>I am solving PDEs on a 1-D domain with a physical length that varies with time as a part of the solution. By change of variables, the discretised space coordinate is in [0,1]. This introduces a coupling between the time-dependent physical domain size
and the PDEs. </div>
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<div>I would like to include the domain-size variable as a DOF in my SNES solve, and this can be accommodated as one of the DM-defined DOFs. However, doing so couples this particular DOF beyond the stencil, to DOFs throughout the domain. So I would like to
modify the auto-generated Jacobian to include non-zeros that capture this coupling (via finite differences).</div>
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<div>For the moment, I am not concerned about breaking the parallelism of the code.</div>
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<div>Any advice on the approach and PETSc functions that would be best suited would be appreciated.</div>
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<div>Thanks,</div>
<div>Richard</div>
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<div>___________________________</div>
<div>Richard Foa Katz<br>
Professor of Geodynamics<br>
Dept Earth Sciences, Univ Oxford<br>
<a href="https://urldefense.us/v3/__http://foalab.earth.ox.ac.uk__;!!G_uCfscf7eWS!b_oizbw-XnXax6rasRGtsC_i3pUtzbYYkWhRQifVKLUsOk-SsyuNX4kFQfNq7mrf4hiQxhTOt7sa1y3C7LIW-yAqSN0y-aIoV9k$">http://foalab.earth.ox.ac.uk</a></div>
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