[daip] [!JWO-767-10295]: aips - COHER

[Lynn D Matthews]

Lynn D Matthews updated #JWO-767-10295
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COHER
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           Ticket ID: JWO-767-10295
                 URL: https://help.nrao.edu/staff/index.php?/Tickets/Ticket/View/3741
           Full Name: Lynn D Matthews
               Email: lmatthew at haystack.mit.edu
             Creator: User
          Department: AIPS Data Processing
       Staff (Owner): -- Unassigned --
                Type: Issue
              Status: Open
            Priority: Default
      Template Group: Default
             Created: 22 August 2013 03:45 PM
             Updated: 22 August 2013 03:45 PM
                 Due: 23 August 2013 03:45 PM (1d 0h 0m)
      Resolution Due: 24 August 2013 03:45 PM (2d 0h 0m)



I apologize for my recent barrage of questions. The last for a while, I hope, concerns COHER.

This task looks like it should be very useful, but the results it reports do not seem to be sensible regardless of the inputs.

For example, running it on a single-source file with all defaults except APARM(3)=0.99, it reports identical (and clearly incorrect) coherence times for all baselines except the first:

 Time range    0  1 23 27.2 -  0  2 13 27.2
----------------------------------------------------------
I  BASELINE  I Number of averaging I Coherence time, min I
----------------------------------------------------------
I   1 -  2   I         14          I        3.544        I
I   1 -  3   I         10          I        4.963        I
I   1 -  4   I         10          I        4.963        I
I   1 -  5   I         10          I        4.963        I
I   1 -  6   I         10          I        4.963        I
etc.

Results  are identical in 31DEC12. A very ancient version (31DEC09) reports:

 Time range    0  1 23 27.2 -  0  2 13 27.2
----------------------------------------------------------
I  BASELINE  I Number of averaging I Coherence time, min I
----------------------------------------------------------
I   1 -  2   I         17          I        2.914        I
I   1 -  3   I         10          I        4.963        I
I   1 -  4   I         34          I        1.336        I
I   1 -  5   I        129          I        0.310        I
I   1 -  6   I        138          I        0.289        I
etc.

The latter, however, complains along the way about  "COHER1: LEASQR: Design matrix inconsistency in row   1".  

Lynn Matthews

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