AIPS HELP file for PCRMS in 31DEC25
As of Wed Dec 11 5:22:02 2024
PCRMS: Finds statistics of a PC table, then flags output PC
INPUTS
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 #
INVERS 0.0 Input PC table version
APARM (1) Amp deviation multiplier
(2) RMS deviation multiplier
(3) antenna for OUTFILE
(4) > 0 -> do NOT write
flagged PC table
(5) > 0 - Report residual
phase statistics
(6) > 0 - ignore the edge
channels but do not flag
PRTLEV -1.0 Print level: -1 very little,
0 what is flagged, 1 various
statistics: rms, bad channels
OUTFILE
Output text file
BADDISK Disks to avoid for scratch
HELP SECTION
PCRMS
Task: This task sorts the input PC table into antenna-time order. In
the first pass through the input PC table, the task computes
the amplitude and phase statistics of the residual PC values
in each IF and polarization in each antenna, after the fit
delays and phases have been removed. It then looks for
channels that deviate from the mean and channels that stick up
compared to their immediate neighbors. In the second pass
through the data, the channel in each IF/polarization/antenna
that sticks out is flagged along with the edge channels. The
delays may be recomputed (APARM(5) > 0) which will allow phase
statistics to be reported along with amplitude ones. The phase
statistics are not currently used for flagging, so the expense
of a second round of delay fitting is only for information
purposes. In the third pass through the input PC table, if
APARM(4) <= 0, the average amplitude and amplitude rms after
flagging the edge channels and those that stuck out is compared
to the overall average and rms for that IF, polarization, and
antenna. Values that deviate too much (APARM(!), and APARM(2))
are flagged and a new, edited PC table is written. At the end
of the third pass, summaries of the number of samples flagged
for bad channels and the number of spectral windows flagged for
bad amplitude and rms are reported.
A file of all values for a particular antenna may be written in
the second pass if APARM(3) > 0 and OUTFILE is specified.
PCHIS is able to plot this file.
Adverbs:
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.
INVERS.....PC table version to be studied. 0 -> highest
APARM......(1) Amplitude averages over an IF that deviate from the
mean for that IF by more than APARM(1) * the rms of
that mean will be flagged. 0 -> 5
(2) Amplitude rmses over an IF that deviate from the
mean of the rmses for that IF by more than APARM(2) *
the rms of that rms will be flagged. 0 -> 5
(3) Antenna for text file
(4) > 0 -> do NOT write a new, flagged PC table
otherwise one is written
(5) > 0 -> Report residual phase statistics - this
requires the second pass through to solve for delays
which is slow.
(6) > 0 => ignore the edge channels in computing average
amplitude and rms in each spectral window but do NOT
flag them in the output pC table. This is useful for
input to PCASS. <= 0 ignore and flag.
PRTLEV.....<0 -> print only a brief summary of the flagging
0 -> print details of what got flagged
>0 -> print which channels stand out, print statistics by
antenna, and print details of what is flagged
OUTFILE....Write up to 8 amplitudes and rmses for every record if
not ' '. The IF average amplitude and its rms for the
first 4 IFs and 2 polarizations are printed. The output
text file may be read by PCHIS to plot histograms.
BADDISK....The disk numbers to avoid for scratch files (sorting
tables mostly).
EXPLAIN SECTION