[daip] Scaling problem for model in VPLOT

[Craig Walker]

We were running UVFIT which leaves a CC table attached to the UV data 
set.  We then tried to plot the data and model using VPLOT.  That works, 
but there is clearly a scaling problem of some sort with the model.  The 
model line shows phase winds at an extremely high rate (seconds) when it 
should have a turn or two across the day.  We then copied the CC table 
to an image that had been made from that data set and re-ran VPLOT, 
pointing to the CC table now attached to the image (exactly the same CC 
table that was attached to the UV data set).  Now the plot comes out fine.

A probably-related problem occurs with PRTCC.  When printing the CC 
table from UVFIT when it is attached to the image file (after TACOP), it 
shows normally.  When printing it while attached to the UV data, the 
positions are in units of kilo-arcsec and the position values all show 
as 0.00.

I suspect that both PRTCC and VPLOT get some sort of scaling information 
from the header that is not really available for a UV data set.  Somehow 
this doesn't cause a crash, but does cause massive confusion about the 
meaning of the position offsets.

We can provide data sets if needed.

Cheers,

Craig

-- 
---------------------------------------------------------------------
     R. Craig Walker            Array Operations Center
     cwalker at nrao.edu           National Radio Astronomy Observatory
     Phone  505 835 7247        P. O. Box O
     Fax    505 835 7027        Socorro NM 87801   USA
---------------------------------------------------------------------