[daip] ISPEC bug when using outprint and ZINC=-1

[Eric Greisen]

Lincoln Greenhill writes:

 > When I dump ISPEC data to a text file and also reverse the axis with
 > zinc=-1, the first column in the text file is not calculated correctly.  
 > I think the problem is with the sign of the channel increment not taking
 > into account the value of zinc. In effect, the column's values are flipped
 > around the reference pixel.

     It was corrected twice in fact - reduced this to once.

 > 
 > This used to be a problem as well for POSSM (c. 2000) when spectra were
 > dumped to text files. I believe one of our students reported the POSSM bug
 > to NRAO.  However, to be safe, I mention it here, in the event it fell
 > between the cracks.

POSSM's text file seems okay now and I can find no reference to fixing
it in the past although POSSM is in nearly constant repair.  I did
find the velocity plot labeling wrong in the case of panels (e.g.
polarization or IFs) bewing attached with axis reversal.

Eric Greisen