[daip] AIPS query

[Eric Greisen]

Catherine Brocksopp writes:

 > Is it possible to plot polarisation vectors, the length of which indicate 
 > the fractional polarisation instead of the linear polarisation? I've used 
 > COMB to create both LP and FP images but am finding PCNTR will only use 
 > the LP image for the vector lengths. If I try using the FP image the 
 > output is:
 > 
 > msslth> PCNTR1: Task PCNTR  (release of 31DEC04) begins
 > msslth> PCNTR1: Do grey scale:
 > msslth> PCNTR1: End labeling:
 > msslth> PCNTR1: Start contouring
 > msslth> PCNTR1: Start polarization lines
 > msslth> PCNTR1: POLDRW: PLOT ROUTINE ERROR  3 QUITTING
 > msslth> PCNTR1: GFINIS: number records used      74
 > msslth> PCNTR1: Successful plot file version    8  created.
 > msslth> PCNTR1: Appears to have ended successfully
 > 

Something besides the fact that it is a fractional polarization image
in the 2nd input name is the source of this mysterious error.  Are you
plotting to the TV or to a plot file?  Try the other.  Try different
values of the PCUT and FACTOR adverb.

I cannot even find where a 3 would come from unless XAS itself returns
that value.  PCNTR does try to defend itself from excessively long
lines etc but such defenses are not perfect.  You do not show what
version of aips you are using - that might affect things since those
defenses have gotten better with time.

Eric Greisen