AIPS HELP file for DEFLG in 31DEC24
As of Thu Apr 18 16:26:59 2024
DEFLG: Flags data based on decorrelation over time, channels
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 #
SOURCES Source list
QUAL -10.0 Source qualifier -1=>all
CALCODE Calibrator code ' '=>all
TIMERANG Time range to purge
SELBAND Bandwidth to select (kHz)
SELFREQ Frequency to select (MHz)
FREQID Freq. ID to select.
BIF 0.0 100.0 Lowest IF number 0=>all
EIF 0.0 100.0 Highest IF number 0=>all
SUBARRAY 0.0 1000.0 Subarray, 0=>all
DOCALIB -1.0 101.0 > 0 calibrate data & weights
> 99 do NOT calibrate weights
GAINUSE CL (or SN) table to apply
DOPOL -1.0 10.0 If >0 correct polarization.
PDVER PD table to apply (DOPOL>0)
BLVER BL table to apply.
FLAGVER -1.0 Flag table version: in
OUTFGVER 0.0 Output FG table version
DOBAND -1.0 10.0 If >0 apply bandpass cal.
Method used depends on value
of DOBAND (see HELP file).
BPVER Bandpass table version
SMOOTH Smoothing function. See
HELP SMOOTH for details.
ANTENNAS Antennas to consider 0=>all
BASELINE Baselines with ANTENNAS
UVRANGE Range spacings in klambda
ICHANSEL Select channels to fit: NOTE
this is start,end,increment
and IF for each region
DOSTOKES -1.0 1.0 > 0 => flag all correlators
if any one found bad
DOALL -1.0 1.0 > 0 => flag all sources when
one is flagged
ICUT 0.0 1.0 Level vector/scalar average
amplitude below which flagged
SOLINT 0.0 Averaging time in sec
DETIME 0.0 Time interval over which
averaging is not done (sec)
BADDISK 0.0 9999.0 Disks to avoid for scratch
HELP SECTION
DEFLG
Task: This task applies the calibration (optionally) to UV data,
sorts them to BT order and then examines the ratio of the
vector-averaged amplitude to the scalar-averaged amplitude.
It writes entries in the flag table when this ratio becomes too
low.
Be aware that a very large number of flag table lines may be
written. Task UVCOP may be used to apply the flags and is the
only task that can handle more than 5000 flags applying to a
single time.
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.
SOURCES....Source list. The task loops over all sources specified.
'*' = all; a "-" before a source name means all except ANY
source named.
QUAL.......Only sources with a source qualifier number in the SU table
matching QUAL will be used if QUAL is not -1.
CALCODE....Sources may be selected on the basis of the calibrator code
given in the SU table.
' ' => any calibrator code selected
'* ' => any non blank code (cal. only)
'-CAL' => blank codes only (no calibrators)
anything else = calibrator code to select.
NB: The CALCODE test is applied in addition to the other
tests, i.e. SOURCES and QUAL, in the selection of sources
to process.
TIMERANG...Time range of the data to be copied. In order: Start day,
hour, min. sec, day, hour, min. sec. Days relative to
reference date.
SELBAND....Bandwidth of data to be selected. If more than one IF is
present SELBAND is the width of the first IF required.
Units = kHz. For data which contain multiple
bandwidths/frequencies the task will insist that some form
of selection be made by frequency or bandwidth.
SELFREQ....Frequency of data to be selected. If more than one IF is
present SELFREQ is the frequency of the first IF required.
Units = MHz.
FREQID.....Frequency identifier to select (you may determine which is
applicable from the OPTYPE='SCAN' listing produced by
LISTR). If either SELBAND or SELFREQ are set, their values
override that of FREQID. However, setting SELBAND and
SELFREQ may result in an ambiguity. In that case, the task
will request that you use FREQID.
BIF........First IF to check. 0=>all.
EIF........Highest IF to check. 0=>all higher than BIF
SUBARRAY...Subarray number to copy. 0=>all.
DOCALIB....If true (>0), calibrate the data using information in the
specified Cal (CL) table for multi-source or SN table for
single-source data. Also calibrate the weights unless
DOCALIB > 99 (use this for old non-physical weights).
GAINUSE....version number of the CL table to apply to multi-source
files or the SN table for single-source files.
0 => highest.
DOPOL......If > 0 then correct data for instrumental polarization as
represented in the AN or PD table. This correction is
only useful if PCAL has been run or feed polarization
parameters have been otherwise obtained. See HELP DOPOL
for available correction modes: 1 is normal, 2 and 3 are
for VLBI. 1-3 use a PD table if available; 6, 7, 8 are
the same but use the AN (continuum solution) even if a PD
table is present.
PDVER......PD table to apply if PCAL was run with SPECTRAL true and
0 < DOPOL < 6. <= 0 => highest.
BLVER......Version number of the baseline based calibration
(BL) table to appply. <0 => apply no BL table,
0 => highest.
FLAGVER....specifies the version of the flagging table to be applied
to the data on input. 0 -> highest, -1 -> none.
OUTFGVER...Flag table version to be used on output for both single-
and multi-source data sets. If OUTFGVER is <= 0 or
greater than FGmax (the previously highest FG version
number), then a new FG table will be created for the new
flags with version FGmax+1. This new table will also
contain the flags applied on input (if any) from FG
version FLAGVER. If OUTFGVER specifies a pre-existing FG
version, then the input flags are not copied even if
OUTFGVER and FLAGVER are not equal.
DOBAND.....If true (>0) then correct the data for the shape of the
antenna bandpasses using the BP table specified by BPVER.
The correction has five modes:
(a) if DOBAND=1 all entries for an antenna in the table
are averaged together before correcting the data.
(b) if DOBAND=2 the entry nearest in time (including
solution weights) is used to correct the data.
(c) if DOBAND=3 the table entries are interpolated in
time (using solution weights) and the data are then
corrected.
(d) if DOBAND=4 the entry nearest in time (ignoring
solution weights) is used to correct the data.
(e) if DOBAND=5 the table entries are interpolated in
time (ignoring solution weights) and the data are then
corrected.
BPVER......Specifies the version of the BP table to be applied
0 => highest numbered table.
<0 => no bandpass correction to be applied.
SMOOTH.....Specifies the type of spectral smoothing to be applied to
a uv database . The default is not to apply any smoothing.
The elements of SMOOTH are as follows:
SMOOTH(1) = type of smoothing to apply: 0 => no smoothing
To smooth before applying bandpass calibration
1 => Hanning, 2 => Gaussian, 3 => Boxcar, 4 => Sinc
To smooth after applying bandpass calibration
5 => Hanning, 6 => Gaussian, 7 => Boxcar, 8 => Sinc
SMOOTH(2) = the "diameter" of the function, i.e. width
between first nulls of Hanning triangle and sinc
function, FWHM of Gaussian, width of Boxcar. Defaults
(if < 0.1) are 4, 2, 2 and 3 channels for SMOOTH(1) =
1 - 4 and 5 - 8, resp.
SMOOTH(3) = the diameter over which the convolving
function has value - in channels. Defaults: 1,3,1,4
times SMOOTH(2) used when input SMOOTH(3) < net
SMOOTH(2).
ANTENNAS...A list of the antennas to be examined. All 0 => all.
If any number is negative then all antennas listed are NOT
to be copied and all others are.
BASELINE...If any elements of BASELINE are non zero then all baselines
between antennas named in ANTENNAS and those named in
BASELINE are specified. If ANTENNAS contains a negative
value then all baselines NOT specified are selected.
UVRANGE....Range of baselines in kilolambda.
ICHANSEL...Select up to 20 groups of channels/IF(s) to fit as sets
of (Start,end,inc,IF), i.e., ICHANSEL = 6,37,1,0,
92,123,1,0 for two regions applyingto all IFs. The first
group for which ICHANSEL(2,i) <= 0 ends the list.
Defaults: Any IF having no group assigned to it, gets a
group including all channels.
ICHANSEL(1,j) defaults to 1,
0 < ICHANSEL(2,j) < ICHANSEL(1,j) defaults to Nchan.
ICHANSEL(3,j) < 1 or > ICHANSEL(2,j)-ICHANSEL(1,j)+1
defaults to 1.
ICHANSEL(4) <= 0 => this group applies to all IFs.
DOSTOKES...> 0 => flag all correlators if any one is found bad,
<= 0 => flag RR and LL separately (RL and LR get flagged
when either RR or LL are flagged).
DOALL......> 0 => flag all cources when one is flagged. Otherwise
the flags are restricted to the source from which they
are found. This may be useful when fast switching using
a SOLINT rather longer than the actual scann length so
that the weak source in between the strong cal is flagged
based on the decorrelation of the cal.
ICUT.......Flag all data < ICUT in vector average amplitude divided
by scalar average amplitude. 0 -> 0.5
SOLINT.....Averaging time in seconds for comparing the vector and
scalar amplitudes. 0 -> 60
DETIME.....A time interval between consecutive samples on a baseline
> DETIME seconds is regarded as a break over which
averaging will not be done. 0 -> 1000000
BADDISK....A list of disks on which scratch files are not to be
placed.
EXPLAIN SECTION