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<p>Thank you for your quick reply.</p>
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<p>I've had to change away from HDF5 to Binary format at an earlier stage in my work due to the former not working well with what I needed, so I would prefer to stick with the binary format.</p>
<p><span style="font-size: 12pt;">I had a quick view at the code for some of the Viewer-routines, but </span><span style="font-size: 12pt;">I'm not well versed in
</span><span style="font-size: 12pt;">gleaning </span><span style="font-size: 12pt;">information about header sizes
</span><span style="font-size: 12pt;">from that. H</span><span style="font-size: 12pt;">ints about what I'm looking for there would be appreciated.</span><span style="font-size: 12pt;"> </span><br>
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<p>Best regards</p>
<p>Peder</p>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>Fra:</b> Matthew Knepley <knepley@gmail.com><br>
<b>Sendt:</b> 4. oktober 2021 15:37:08<br>
<b>Til:</b> Peder Jørgensgaard Olesen<br>
<b>Cc:</b> petsc-users@mcs.anl.gov<br>
<b>Emne:</b> Re: [petsc-users] Skipping data when reading from binary file</font>
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<div dir="ltr">On Mon, Oct 4, 2021 at 9:26 AM Peder Jørgensgaard Olesen via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov">petsc-users@mcs.anl.gov</a>> wrote:<br>
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<p>Hello</p>
<p>I have a binary file in which a mix of different objects is stored (Vecs, Mats, PetscInts). I can read each element just fine using VecLoad, MatLoad, and PetscIntView, provided they're read in the order in which they were put in the binary. What I would
like to do is to skip the reading of any unneeded element, instead proceeding directly to the next one. I tried using PetscBinarySeek() for this, as shown in the attached code. This produces segmentation faults, suggesting that the file pointer isn't going
where I want it to.</p>
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<div>There is header information you also have to skip for each object.</div>
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<div>We can go over the sizes for that (it is best just to look at the code), but that is fragile. A more robust way to achieve this random</div>
<div>access is to use HDF5 and name the objects.</div>
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<div> Thanks,</div>
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<div> Matt</div>
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<p>Any suggestions as to what I'm doing wrong here?</p>
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<p>Best regards,</p>
<p>Peder</p>
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