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<p class="MsoNormal"><span style="font-size:11.0pt">You should be able to use put_var_all, with everyone calling the call, and just have some processes indicate they have nothing to write? -- Rob<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><b><span style="font-size:12.0pt;color:black">From:
</span></b><span style="font-size:12.0pt;color:black">parallel-netcdf <parallel-netcdf-bounces@lists.mcs.anl.gov> on behalf of Pascale Garaud <pgaraud@soe.ucsc.edu><br>
<b>Date: </b>Tuesday, May 10, 2022 at 10:48 AM<br>
<b>To: </b>parallel-netcdf@lists.mcs.anl.gov <parallel-netcdf@lists.mcs.anl.gov><br>
<b>Subject: </b>Using parallel write with subset of processors<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">Hello<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">I am trying to understand what would be the best way to <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">use the library to write data that is contained in only a subset of the <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">processors in my communicator. (Specifically, my problem is that I have a 3D dataset, and would like to save only a slice of that dataset to file, and the slice is contained in only a subset of the processors). <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"><br>
Is there a best way to do that efficiently? The code currently uses a collective PUT_VAR_ALL to write the 3D dataset to file, but that would not work for the slice (and hangs when I try). <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"><br>
I could just copy the whole data for the slice into a single processor, and then do an "independent" write for that processor, but that doesn't seem to be very efficient. <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">I tried to understand how to use IPUT instead, but I am very confused about the syntax / procedure, especially given that all of the examples I have seen end up using all processors for the write. <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">I am very much a beginner in this process so any help would be greatly appreciated, thank you! <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">Pascale Garaud. <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">-- <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">--------------------------------------------------------------------------------------------------------------<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">Pascale Garaud<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">Professor in Applied Mathematics<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">UC Santa Cruz, California<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">(831)-459-1055<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">--------------------------------------------------------------------------------------------------------------<o:p></o:p></span></p>
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