AIPS HELP file for CLOSE in 31DEC24
As of Thu Apr 25 21:31:05 2024
CLOSE: Plots data from a u,v data base, model from a CC file
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 3.0 Input UV file disk unit #
SRCNAME Source name
QUAL -10.0 Source qualifier -1=>all
CALCODE Calibrator code ' '=>all
SELBAND Bandwidth to select (kHz)
SELFREQ Frequency to select (MHz)
FREQID Freq. ID to select.
BCHAN 0.0 4096.0 Low channel # averaged 0=>1
ECHAN 0.0 4096.0 High channel # averaged
BIF 0.0 100.0 Low IF # averaged 0=>1
EIF 0.0 100.0 High IF # averaged 0=>max
UVRANGE 0.0 Range of projected spacings
(thousands of wavelengths)
TIMERANG Time: start day,hr,min,sec
stop day,hr,min,sec.
ANTENNAS Antennas to include/exclude
STOKES Stokes' parameter - 1 or 2
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 Flag 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
SUBARRAY Subarray number 0=all.
SOLINT Time interval over which to
average data in order to
form closure phase (mins).
See HELP for hints on how
to use this.
OPTYPE 'PHAS' or 'AMP '
OPCODE If OPCODE = 'INDE' will use
all independent triangles or
quadrangles (recommended)
' ' => use all possible ones
See HELP for more info.
PIXRANGE Plot scale if PIXR(2)>PIXR(1)
SYMBOL 0.0 24.0 Symbol to use when plotting.
0 => 2 (an X)
1 - 24, standard types
FACTOR -10.0 10.0 Scale symbol plotted: < 0
-> connect points
LTYPE -410.0 410.0 Type of labeling: 1 border,
2 no ticks, 3 - 6 standard,
7 - 10 only tick labels
<0 -> no date/time
DOTV -1.0 1.0 > 0 Do plot on the TV, else
make a plot file
GRCHAN 0.0 8.0 Graphics channel 0 => 1.
XYRATIO 0.0 X/Y ratio 0 -> fit TV or 1 PL
DOPRINT 0 - no print, -3 brief
OUTTEXT Name of output log file,
No output to file if blank
BADDISK Disks to avoid for scratch
HELP SECTION
CLOSE
Type: Task
Use: Plots closure phase or amplitude from a u,v data base making a
plot file or using the TV. It averages over all triangles or
quadrangles allowed by OPCODE and ANTENNAS and over all
integration intervals allowed by TIMERANG and SOLINT.
For a triangle of antennas a, b, and c, the closure phase is
Ph_ab - Ph_ac + Ph_bc
which should be zero for a point source or a gain file
(data/model) no matter what the calibration. For a quadrangle of
antennas a, b, c, and d, the closure amplitude is defined to be
ln [ (A_ab * A_cd) / (A_ac * A_bd) ]
which should also be zero for a point source or a gain file no
matter what the calibration.
Closure information is produced by the following tasks:
CLPLT Plots closure phases for individual triangles as a
funtion of time.
CAPLT Plots closure amplitudes for individual quadrangles as
a funtion of time.
EVACL Computes the RMS of closure phase and amplitude as a
function of IF for an individual Stokes.
EVAUV Computes two data sets: data-model and data/model. The
closure RMSes of the latter may be computed as
functions of polarization and IF. Other statistics
are computed and plotted.
CLOSE Computes the RMS closure phase or amplitude as a
function of spectral and IF channel. A plot is
produced and a text file may be written.
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.
SRCNAME....Source name. If the data are in a multi-source file, plot
the visibility for the source specified. If the data are in
a single source file no source name need be specified.
QUAL.......Only sources with a source qualifier number in the SU table
matching QUAL will be used if QUAL is not -1.
CALCODE....Calibrators may be selected on the basis of the calibrator
code:
' ' => 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. CALSOUR and QUAL, in the selection of sources
for which to determine solutions.
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, 0=> all
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, 0=> all
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
overide that of FREQID, however setting SELBAND and SELFREQ
may occasionally result in an ambiguity, in which case the
task will request that you use FREQID.
BCHAN......Start channel. 0 => 1
ECHAN......End channel. 0 => max
BIF........Start IF number to plot. 0 => 1
EIF........End IF number to plot. 0 => max
UVRANGE....Range (min, max) of projected baselines to include
0,0 => all baselines
TIMERANG...The specified time range.
1 = Start IAT day (day 0 = first day in data base)
2 = Start IAT hour
3 = Start IAT minute
4 = Start IAT second
5 = Stop IAT day (day 0 = first day in data base)
6 = Stop IAT hour
7 = Stop IAT minute
8 = Stop IAT second
start IAT = 0 => beginning
stop IAT = 0 => end of time.
STOKES.....Specifies the single Stokes type to be plotted:
Types with 2 polarization are 'HALF', 'RRLL', 'VVHH'.
Good types with 1 polarization are 'RR', 'LL', 'VV', 'HH'
Dubious ones that are recognized are 'I', 'Q', 'U', 'V',
'LR', 'RL', 'VH', 'HV'. ' ' => 'HALF'.
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
multisource 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. 0 => highest numbered table.
<0 => no flagging to be applied.
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 either
plotted (if APARM(8)=2) or applied (if DOBAND > 0
and APARM(8) .NE. 2). 0 => highest numbered table.
<0 => no bandpass correction to be applied.
plotted (if APARM(8)=2) or applied (if DOBAND > 0
and APARM(8) .NE. 2). 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).
SUBARRAY...The subarray number desired. 0=> all.
DOEBAR.....If = 0 => do not plot error bars on data
if = 1 => do plot error bars
This works only if the data weights are in fact 1/sigma^2
with the sigma on the same scale as the visibilities.
Data weights that are simply the count of integration
time (or some such) will not give valid error bars.
OPTYPE.....'AMP ' -> plot closure amplitude, else plot closure phase.
OPCODE.....If OPCODE = 'INDE' then all independent
triangles/quadrangles are included. Otherwise, all possible
triangles/quadrangles are included which is a great many.
PIXRANGE...Plot range to use when PIXRANGE(2) > PIXRANGE(1).
SOLINT.....The time interval (minutes) over which to average the data
in order to form the closure phase. It is possible,
especially on correlators which only correlate a subset of
the available stations simultaneously that the time tags
associated with visibility values on different baselines
differ. Therefore one has to specify a time interval over
which to average the data to form the closure phase. If
this is not necessary with your data, set
SOLINT <= 0.9 * data integration time.
You should experiment a little with this parameter. If the
fringe rate for the source is fairly rapid, then it is very
important to have the sampling be the same on all baselines
in each triangle. Otherwise, samples at slightly different
times will be combined but the phases will not cancel
properly. Use of a very small value of SOLINT (but > 0)
will cause inadequately aligned data to be discarded in
order to avoid misleadingly high closure phases.
If SOLINT < 0, the task will form a closure phase as soon
as it has accumulated at least one sample for each of the
three baselines in the triangle. The closure phases will
then be averaged over SOLINT minutes. This averaging is
a vector averaging to avoid difficulties with 2 pi
ambiguities.
SYMBOL.....Symbol to use when plotting.
1: Plus sign 13: Star of David
2: Cross (X) 14: Seven-pointed star
3: Circle 15: Eight-pointed star
4: Box 16: Nine-pointed star
5: Triangle 17: Ten-pointed star
6: Diamond 18: 11-pointed star
7: Pentagon 19: 12-pointed star
8: Hexagon 20: 13-pointed star
9: Septagon 21: 14-pointed star
10: Octagon 22: Plus (+) with gap
11: Nine-gon 23: Cross (X) with gap
12: Five pointed star 24: Vertical line
FACTOR.....Scale plot symbols by FACTOR 0 -> 1.
If FACTOR < 0, draw lines between the points and use
abs(FACTOR) to scale the points plotted. To have
no points plotted, set -0.2 <=FACTOR < 0.
LTYPE......Labelling type, see HELP LTYPE for details:
1 = border, 2 = no ticks, 3 or 7 = standard, 4 or 8 =
relative to ref. pixel, 5 or 9 = relative to subimage
(BLC, TRC) center, 6 or 10 = pixels. 7-10 all labels
other than tick numbers and axis type are omitted.
Less than 0 is the same except that the plot file
version number and create time are omitted.
Add n * 100 to alter the metric scaling.
DOTV.......> 0 => plot directly on the TV device, otherwise
make a plot file for later display on one or
more devices (including the TV if desired).
GRCHAN.....Graphics channel (1 - 7) to use for line drawing.
0 => 1.
XYRATIO....Scale the X axis longer than the Y by XYRATIO.
If DOTV > 0, 0 -> fit to the TV window
If DOTV <= 0, 0 -> 1.
DOPRINT....Print control:
= 0 => no printing, > 0 print to terminal,
< 0 -> print to OUTTEXT if not blank, else no print
= -2 => suppress page feed characters in page headings
= -3 => suppress most header information including all
page headings.
OUTTEXT....Output file to log closure phase/amplitude rms spectra.
File created if it does not exist and appended to if it
already exists. Nothing is written to a file if the name
is blank OR DOPRINT = 0. File name should contain
directory and file parts, i.e,
'LOCAL:CLOSE.OUT' or 'HOME:IMPORTANT.POINTS'.
BADDISK....The disk numbers to avoid for scratch files (sorting
tables mostly).
EXPLAIN SECTION