[daip] CLIP, and Stokes Visibilities

[Eric Greisen]

On 12/02/2014 12:57 AM, rperley at nrao.edu wrote:
> Eric:
>
> As you know, I'm a great believer in CLIP for ridding ourselves of RFI.
>
> My L-band beam holography data is now well calibrated for polarization and
> gain, so I thought I'd use 'CLIP' to flag on the basis of Stokes 'V'.  So
> I told it to clip on Stokes 'IQUV', and used APARM(2) to set a low (5%)
> maximum fractional cross-polarization level.  And I used BPARM(2)=1 to
> have all correlations flagged if any one of them went over the limit.
>
> But the results of this were not what I expected.  The Stokes 'V' data,
> after removing the flagged data, has fractional values remaining as high
> as 1.0!  I listed the FG file, and it has '1111' in all the right places,
> seemingly indicating that the clipping was for all correlations.
>
> Is there any reason what I did was not correct?
>
> Rick
>

There was a type in CLIP so the V clipping was not supported properly.
Fixed tomorrow.

Eric