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<p class="MsoNormal"><span style="font-size:18.0pt">Hi Hassan,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:18.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:18.0pt">Are there any routines that are more selective about the tiles included in the sum?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:18.0pt">I am not aware of any.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:18.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:18.0pt">Is there a routine that works like global_sum_tile.F but for element-wise vector addition instead of single values?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:18.0pt">The subroutine global_vec_sum.F might be what you are looking for.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:18.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:18.0pt">Best,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:18.0pt">Ou Wang<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></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">MITgcm-support <mitgcm-support-bounces@mitgcm.org> on behalf of Hassan Mason <hcm7920@nyu.edu><br>
<b>Date: </b>Thursday, June 22, 2023 at 9:53 AM<br>
<b>To: </b>mitgcm-support@mitgcm.org <mitgcm-support@mitgcm.org><br>
<b>Subject: </b>[EXTERNAL] [MITgcm-support] Question about MPI sums<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:18.0pt">Hi all,<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:18.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:18.0pt">I'm currently constructing an addition to MITgcm and I'm stuck implementing it with MPI.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:18.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:18.0pt">I have a value that's calculated for each tile and I need to sum over all tiles aligned in a horizontal direction. In other words, I want to sum over a specific column of tiles, and in the end each tile would
know the sum of the column to which it belongs.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:18.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:18.0pt">I see there are routines like global_sum_tile.F that perform a global sum, but are there any routines that are more selective about the tiles included in the sum? Alternatively, is there a routine that works
like global_sum_tile.F but for element-wise vector addition instead of single values?<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:18.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:18.0pt">Thanks!<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:18.0pt">Hassan Mason<o:p></o:p></span></p>
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