AIPS NRAO AIPS HELP file for CLOSE in 31DEC22



As of Wed Nov 30 6:49:30 2022


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 #
SOURCES                            Source list
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.
  SOURCES....Source list.  If the data is a multi-source file CLOSE will
             plot the visibility for the first source specified. If the
             data is 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           12: Five pointed star
             2: Cross (X)           13: Star of David
             3: Circle              14: Seven-pointed star
             4: Box                 15: Eight-pointed star
             5: Triangle            16: Nine-pointed star
             6: Diamond             17: Ten-pointed star
             7: Pentagon            18: 11-pointed star
             8: Hexagon             19: 12-pointed star
             9: Septagon            20: 13-pointed star
             10: Octagon            21: 14-pointed star
             11: Nine-gon           22: Plus with gap
                                    23: Vertical line
                                    24: Cross with gap
             0 => 23 =  '|' (i.e. vertical lines).
  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


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