[daip] Re: IT's definitley STRANGE UVCOP

[Hans-Rainer Kloeckner]

On Sun, 11 Sep 2005, Eric Greisen wrote:

> Hans-Rainer Kloeckner writes:
>
> > Sorry I'm somehow confused! I run into the
> > following problem. Using UVCOP to delete some visibilities works ONLY
> > if the BCHAN and ECHAN in the flag table is set to 1 0 otherwise UVCOP
> > does not delete anything. I did the following experiment on several
> > datasets:
> >
> > I produce 2 flag tables with UVFLG one with
> > BCHAN 0, ECHAN 0 and one with BCHAN 40, ECHAN 41.
> >
> > UVCOP only dropped some vis. records in the first case and
> > does nothing in the secound.
> >
> > Is there some hidden knowledge why? If not and I hope it's not my AIPS
> > version, do you see an easy way to fix that problem ?
> >


Hi Eric,

Thank you for your reply. You won the bet !!! So I guess a beer 
or soft drink in October is on me !

cheers

hans


> In the 2nd case it will not drop a record, just flag channels 40 and
> 41 inside that record.  I bet if you run PRTUV on CHANNEL=40 you will
> see that the UVCOP output has negative or 0 weight where the channel
> is to be flagged.  Note that a UV data record contains all of the
> channels and will be dropped only if all of the channels (and all of
> the IFs and all of the polarizations) are flagged.
>
> Eric Greisen
>

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