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<div class="">I think it depends on the functional for which the sensitivities are calculated. For most cases, the objective functional should not be sensitive to the step sizes when a converged solution is achieved. What the adapter does is just to choose
a step size so that the solution is accurate within certain tolerances. Of course, if the adapter is not doing a good job (e.g. choosing a step size that leads to instability), not only the sensitivities are influenced but also the solution is inaccurate.</div>
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<div class="">Hong (Mr.)</div>
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<div class="">On Oct 28, 2020, at 4:54 PM, Salazar De Troya, Miguel via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov" class="">petsc-users@mcs.anl.gov</a>> wrote:</div>
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<span style="font-size: 11pt;" class="">Hello,</span><span style="" class=""><o:p class=""></o:p></span></div>
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<span style="font-size: 11pt;" class=""> </span><span style="" class=""><o:p class=""></o:p></span></div>
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<span style="font-size: 11pt;" class="">I saw in the TSAdjoint paper that adjoints for adaptive time stepping schemes are supported. Given that these schemes usually involve nondifferentiable functions to pick the time step, are the sensitivities also nondifferentiable
at certain points? Does one need to be careful when using adjoints with adaptive time steps?</span><span style="" class=""><o:p class=""></o:p></span></div>
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<span style="font-size: 11pt;" class=""> </span><span style="" class=""><o:p class=""></o:p></span></div>
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<span lang="ES" style="font-size: 11pt;" class="">Thanks</span><span lang="ES" style="" class=""><o:p class=""></o:p></span></div>
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<span lang="ES" style="font-size: 11pt;" class="">Miguel</span><span lang="ES" style="" class=""><o:p class=""></o:p></span></div>
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<span lang="ES" style="font-size: 11pt;" class=""><o:p class=""> </o:p></span></div>
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<span lang="ES" style="font-size: 11pt;" class=""><o:p class=""> </o:p></span></div>
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<span lang="ES" style="font-size: 9pt; font-family: Consolas;" class="">Miguel A. Salazar de Troya</span><span lang="ES" style="font-size: 10.5pt;" class=""><o:p class=""></o:p></span></div>
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<span style="font-size: 9pt; font-family: Consolas;" class="">Postdoctoral Researcher, Lawrence Livermore National Laboratory</span><span style="font-size: 10.5pt;" class=""><o:p class=""></o:p></span></div>
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<span style="font-size: 9pt; font-family: Consolas;" class="">B141</span><span style="font-size: 10.5pt;" class=""><o:p class=""></o:p></span></div>
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<span style="font-size: 9pt; font-family: Consolas;" class="">Rm: 1085-5</span><span style="font-size: 10.5pt;" class=""><o:p class=""></o:p></span></div>
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<span style="font-size: 9pt; font-family: Consolas;" class="">Ph: 1(925) 422-6411</span></div>
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