[daip] VLANT problem

[Eric Greisen]

Kim Herrmann wrote:
> Dear Eric,
> 
> I have recently started at Lowell Observatory as Deidre Hunter's postdoc 
> to work on her LITTLE (Local Irregulars That Trace Luminosity Extremes) 
> THINGS (The H I Nearby Galaxy Survey) project.  Since I'm new to radio 
> astronomy, Deidre has been teaching me about reducing VLA data with 
> AIPS.  However, we were following a LITTLE THINGS AIPS recipe with new 
> data (D array of DDO 52 with only one frequency) when we had the 
> following problem with VLANT:
> 
>  >default VLANT
>  >getn 3
> AIPS 1: Got(1)   disk= 1  user=   4   type=UV   DDO52-D.LINCOP.1
>  >go
> 
> This returned:
> 
> tortue> VLANT1: Task VLANT  (release of 31DEC08) begins
> tortue> VLANT1: /tmp/baselines.vlais08 copied from the VLA web site
> tortue> VLANT1: ZABORS: signal 11 received
> tortue> VLANT1: ABORT!

We have found the source of this problem finally - when we got our hands 
on a Mac laptop that showed the problem.  It turns out that, if the 
first line in the text file is a null (not even 1 blank) then the Z 
routine that reads the file aborts - but only on some Macs and not 
others and on no Linux machines although the Z routines are identical.
Unfortunately, an initial null line had crept in to the 2009 text file 
causing the problem.  We have repaired that file.  VLANT should now work 
as intended.

Eric Greisen