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<p class="MsoNormal">Dear Eric,</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">I am Jay. I am a postdoctoral research candidate at CSIRO, Australia. I am facing a specific issue with running AIPS task CVEL on my computer (MacBook Pro 2023, chip: Apple M2 Pro, MacOS: Sonoma 14.6.1). I am running AIPS DEC2023 version
(I have also tried latest DEC2024 version as well, but the same issue persisted).
</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Basically, the issue is that though CVEL runs successfully on my system as I can see in message log, but it does not execute any the velocity shift in the data. I have double checked this with POSSM task (by comparing the before CVEL data
(aka uvdata used in CVEL input) and uvdata created after running CVEL task). The output message log for CVEL run in the message window is also not the usual CVEL output messages that I used to see when I was using different machine (Apple MacBook Pro 2018,
and same AIPS version DEC2023).</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">My uvdata is the VLBA spectral line VLBI data from the BeSSeL project. I am trying to correct for the doppler shift in my spectral line data (22 GHz water maser emission spectra).
</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Since the same issue persisted with both AIPS versions (DEC2023 and DEC2024), fearing that it might an issue arising because of the “Apple M2 chip” computer, I tried running the CVEL task on that same data but in a different system (using
Ubuntu platform in Windows). The same AIPS versions was used (both DEC2023 and DEC2024). This time, CVEL performed correctly and as expected (please see attached files for message logs). So now I am more certain that the issue with CVEL not performing as expected
is: the Apple M2 Chip system. </p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am writing to you in hope that you might have encountered/heard about this issue from other AIPS users, and there is a solution for that. If indeed that’s the case, I kindly request you to please help me with this. Please guide me on
what do I need to do to make CVEL task work properly with my system (MacBook Pro 2023, chip: Apple M2 Pro, MacOS: Sonoma 14.6.1). I would highly appreciate your help in this!
</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">For more details about this, I’ve attached some files which show the CVEL run log when running on my system (MacBook Pro 2023, chip: Apple M2 Pro, MacOS: Sonoma 14.6.1) and through Ubuntu. You can see the difference in the message logs
for the CVEL task between two occasions. </p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Please let me know if you need any further information on this from me.
</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks again for your help in advance! I look forward hearing from you!</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Kind regards,</p>
<p class="MsoNormal">Jay</p>
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