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<div class=""><span class="">Tyler,</span></div>
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The quickest solution is to use TSTrajectory as Matt mentioned. You can add the following command line options to save the solution into a binary file under a folder at each time step.<br class="">
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</span><span class="">-ts_save_trajectory -ts_trajectory_type visualization </span><span class=""><br class="">
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The folder name and the file name can be customized with </span><span class="">-ts_trajectory_dirname and -ts_trajectory_file_template.<br class="">
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</span><span class="">If you want to load these files into Matlab, you can use some scripts in share/petsc/matlab/ such as PetscReadBinaryTrajectory.m and PetscBinaryRead.m.<br class="">
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</span><span class="">The python versions of these scripts are available in lib/petsc/bin/.<br class="">
</span><span class=""><br class="">
</span><span class="">Hong(Mr.)<br class="">
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<div class="">On Dec 13, 2022, at 12:14 AM, Guglielmo, Tyler Hardy via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov" class="">petsc-users@mcs.anl.gov</a>> wrote:</div>
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Hi all,<o:p class=""></o:p></div>
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I am a new PETSc user (and new to MPI in general), and was wondering if someone could help me out with what I am sure is a basic question (if this is not the appropriate email list or there is a better place please let me know!).<o:p class=""></o:p></div>
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Basically, I am writing a code that requires a solution to an ODE that will be used later on during runtime. I have written the basic ODE solver using TSRK, however I haven’t thought of a good way to store the actual solution at all time steps throughout the
time evolution. I would like to avoid writing each time step to a file through the monitor function, and instead just plug each time step into an array.<o:p class=""></o:p></div>
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How is this usually done? I suppose the user defined struct that gets passed into the monitor function could contain a pointer to an array in main? This is how I would do this if the program wasn’t of the MPI variety, but I am not sure how to properly declare
a pointer to an array declared as Vec and built through the usual PETSc process. Any tips are greatly appreciated!<o:p class=""></o:p></div>
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Thanks for your time,<o:p class=""></o:p></div>
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Tyler<o:p class=""></o:p></div>
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+++++++++++++++++++++++++++++<o:p class=""></o:p></div>
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Tyler Guglielmo<o:p class=""></o:p></div>
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Postdoctoral Researcher<o:p class=""></o:p></div>
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Lawrence Livermore National Lab<o:p class=""></o:p></div>
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Office: 925-423-6186<o:p class=""></o:p></div>
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Cell: 210-480-8000<o:p class=""></o:p></div>
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+++++++++++++++++++++++++++++</div>
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