AIPS HELP file for VPFLG in 31DEC20
As of Tue Jul 7 4:34:07 2020
VPFLG: Task to insure full flagging whenever 1 cor is flagged
INNAME Input UV file name (name)
INCLASS Input UV file name (class)
INSEQ 0.0 9999.0 Input UV file name (seq. #)
INDISK 0.0 9.0 Input UV file disk unit #
OUTNAME Output UV file name (name)
OUTCLASS Output UV file name (class)
OUTSEQ -1.0 9999.0 Output UV file name (seq. #)
OUTDISK 0.0 9.0 Output UV file disk unit #.
BCHAN 0.0 8192.0 Lower channel to check
ECHAN 0.0 8192.0 Uppermost channel to check
DOIFS -1.0 1.0 > 0 => flag full IF if >=1
channel is flagged
> 1 => flag all IFs if 1 bad
OPCODE 'CROS' to flag cross-hands
on a parallel flagged, else
flag all on any one flagged
FQCENTER >= 0 -> center frequency axis
Task: On-line systems flag data on the assumption that the user
wishes to retain as much data as possible. Later AIPS tasks
tend to make this assumption as well. In the on-line case,
only 1 antenna-polarization is flagged, i.e. 2 of the 4
full-polarization correlators. Off-line, when, for example, RR
is found bad, RR, RL, and LR are flagged but not LL. Observers
of circularly polarized sources may find this undesirable.
VPFLG copies the data, flagging all correlators in a time
sample, IF, antenna pair if any one of them is flagged.
Spectral channels BCHAN-ECHAN only are checked since the
outermost may be flagged due to bandpass calibration.
If you are not interested in circular polarization you may
still wish to insure thatthe cross-hand polarizations are both
flagged when one of the parallel-hand polarizations is flagged.
OPCODE='CROS' requests this less-draconian mode.
INNAME.....Input UV file name (name). Standard defaults.
INCLASS....Input UV file name (class). Standard defaults.
INSEQ......Input UV file name (seq. #). 0 => highest.
INDISK.....Disk drive # of input UV file. 0 => any.
OUTNAME....Output UV file name (name). Standard defaults.
May be the same file as the input.
OUTCLASS...Output UV file name (class). Standard defaults.
OUTSEQ.....Output UV file name (seq. #). 0 => highest unique
OUTDISK....Disk drive # of output UV file. 0 => highest with
space for the file.
BCHAN......Lowest channel to check. 0 -> 1
ECHAN......Highest channel to check. <BCHAN -> max.
DOIFS......> 0 => flag full IF if >= 1 channel is bad
> 1 => flag all IFs if one is bad
<= 0 => handle channels, IFs separately - RECOMMENDED
OPCODE.....'CROS' => flag RL and LR when RR or LL is flagged, flag
XY and YX when XX or YY is flagged.
else => flag all polarizations whenever any one or
more is flagged.
FQCENTER...>= 0 => Change frequency axis reference pixel to
Nchan / 2 + 1
else => do not change reference pixel