[daip] Fwd: Re: Fwd: Re: Nasmyth mount not working in NEW/TST ?

[Eric Greisen]

Thomas Krichbaum wrote:
> Hi Eric,
> 
> I do not really understand what ANCHECK does.
> I run ANCHECK in version TST (31DEC10). 
> 
> After ANCHECK I was running PRTAN, but see no obvious changes. 
> I still get 
> XYZHAND = 'RIGHT   '    TFRAME = '?????   '
> 
> Is ANCHECK supposed to modify the AN#1 table ?
> 
> It looks as if AIPS TST, once touching the data reverses the BY sign. But I was
> unable to change it back to the old convention, once the file was touched. 
> What can I do to undo the BY changes ?
> 
> (Obviously, we need full forward and backward flexibility between old, new and tst. I 
> don't want to screw up existing old data sets (e.g from 2005-2007), which are partially 
> analyzed with the 'wrong' coordinate convention.)

I cannot help you.  each version of AIPS stands on its own although I 
work hard to get forward compatibility.  I cannot (nor does anyone in 
the industry) grant backward compatibility except by changing 31DEC08 
into 31DEC10.

If you reverse the By signs in data then 31DEC09 and 31DEC10 will do the 
wrong thing wherever it may matter (and there only a few places). 
ANCHECK is a procedure that makes sure that the By values are correct so 
far as can be known (i.e. stations recognized).  You should forever see 
the new keywords in AN files.

Eric Greisen