Difference between revisions of "Applycal"

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== Help on applycal task: ==
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{{applycal}}
 
 
<pre>
 
Apply calibrations solutions(s) to data
 
 
 
 
 
      Applycal reads the specified gain calibration tables, applies
 
      them to the (raw) data column (with the specified selection),
 
      and writes the calibrated results into the corrected column.
 
      This is done in one step, so all available calibration tables must
 
      be specified.  Include parang, gaincurve, opacity is used in
 
      obtaining previous calibration tables.
 
 
 
      Applycal will overwrite existing corrected data.
 
 
 
      All calibration tables (both temporal, frequency, polarization
 
      calibrations) are specified in the gaintable parameter.  The
 
      calibration values associated with a restricted list of fields
 
      can also be selected for each table in gainfield
 
 
 
      See task accum for instructions on forming calibration
 
      incrementally.  See task split for copying out any portion of the data
 
      and selected columns to a new visibility file.
 
 
 
      Keyword arguments:
 
      vis -- Name of input visibility file
 
              default: < none>; example: vis='ngc5921.ms'
 
 
 
      --- Data Selection: the data to which the calibration will be applied
 
        (see help par.selectdata for more detailed information)
 
 
 
      field -- Select field id(s) or field name(s) to apply calibration.
 
                [run listobs to obtain the list id's or names]
 
              default: ''=all fields
 
              If field string is a non-negative integer, it is assumed a field index
 
                otherwise, it is assumed a field name
 
              field='0~2'; field ids 0,1,2
 
              field='0,4,5~7'; field ids 0,4,5,6,7
 
              field='3C286,3C295'; field named 3C286 adn 3C295
 
              field = '3,4C*'; field id 3, all names starting with 4C
 
    spw -- Select spectral window/channels
 
              type 'help par.selection' for more examples.
 
            spw='0~2,4'; spectral windows 0,1,2,4 (all channels)
 
            spw='<2';  spectral windows less than 2 (i.e. 0,1)
 
            spw='0:5~61'; spw 0, channels 5 to 61, INCLUSIVE
 
            spw='*:5~61'; all spw with channels 5 to 62
 
            spw='0,10,3:3~45'; spw 0,10 all channels, spw 3, channels 3 to 45.
 
            spw='0~2:2~6'; spw 0,1,2 with channels 2 through 6 in each.
 
            spw='0:0~10;15~60'; spectral window 0 with channels 0-10,15-60
 
                      NOTE ';' to separate channel selections
 
            spw='0:0~10^2,1:20~30^5'; spw 0, channels 0,2,4,6,8,10,
 
                  spw 1, channels 20,25,30
 
      selectdata -- Other data selection parameters
 
              default: True
 
      timerange  -- Select data based on time range:
 
              default = '' (all); examples,
 
              timerange = 'YYYY/MM/DD/hh:mm:ss~YYYY/MM/DD/hh:mm:ss'
 
              Note: if YYYY/MM/DD is missing dat defaults to first day in data set
 
              timerange='09:14:0~09:54:0' picks 40 min on first day
 
              timerange= '25:00:00~27:30:00' picks 1 hr to 3 hr 30min on next day
 
              timerange='09:44:00' data within one integration of time
 
              timerange='>10:24:00' data after this time
 
      uvrange -- Select data within uvrange (default units meters)
 
              default: '' (all); example:
 
              uvrange='0~1000kl'; uvrange from 0-1000 kilo-lamgda
 
              uvrange='>4kl';uvranges greater than 4 kilo lambda
 
      antenna -- Select data based on antenna/baseline
 
              default: '' (all)
 
              If antenna string is a non-negative integer, it is assumed an antenna index
 
                otherwise, it is assumed as an antenna name
 
              antenna='5&6'; baseline between antenna index 5 and index 6.
 
              antenna='VA05&VA06'; baseline between VLA antenna 5 and 6.
 
              antenna='5&6;7&8'; baseline 5-6 and 7-8
 
              antenna='5'; all baselines with antenna index 5
 
              antenna='05'; all baselines with antenna name 05--vla antenna 5.
 
              antenna='5,6,10'; all baselines with antennas 5,6 and 10
 
      scan -- Scan number range
 
      msselect -- Optional complex data selection (ignore for now)
 
 
 
      --- Calibration files to apply
 
      gaintable -- Gain calibration table(s) to apply
 
              default: '' (none);
 
              examples: gaintable='ngc5921.gcal'
 
                  gaintable=['n5921.ampcal','n5921.phcal','n5921.bpass']
 
              All gain table types: 'G', GSPLINE, 'T', 'B', 'BPOLY', 'D's'
 
                  can be applied.
 
      gainfield -- Select a subset of calibrators from each gaintable
 
              default:'' ==> all sources in table;
 
              same syntax as field
 
              example: gainfield='0~3'
 
                        gainfield=['0~3','4~6']  (for multiple gaintables)
 
      interp -- Interpolation mode (in time) to use for each gaintable
 
                default: '' --> 'linear' for all gaintable(s)
 
                example: interp='nearest'
 
                        interp=['nearest','linear']  (for multiple gaintables)
 
                Options: 'nearest', 'linear', 'aipslin'
 
      spwmap -- Spectral windows combinations to form for gaintable(s)
 
                        gainfield=['0~3','4~6']  (for multiple gaintables)
 
      interp -- Interpolation mode (in time) to use for each gaintable
 
                default: '' --> 'linear' for all gaintable(s)
 
                example: interp='nearest'
 
                        interp=['nearest','linear']  (for multiple gaintables)
 
                Options: 'nearest', 'linear', 'aipslin'
 
      spwmap -- Spectral windows combinations to form for gaintable(s)
 
              default: [] (apply solutions from each spw to that spw only)
 
              Example:  spwmap=[0,0,1,1] means apply the caltable solutions
 
                        from spw = 0 to the spw 0,1 and spw 1 to spw 2,3.
 
                        spwmap=[[0,0,1,1],[0,1,0,1]]  (for multiple gaintables)
 
                       
 
          Complicated example:
 
 
 
            gaintable=['tab1','tab2','tab3']
 
            gainfield='3C286'
 
            interp=['linear','nearest']
 
            spwmap=[[],[0,0,2]]
 
           
 
            This means: apply 3 cal tables, selecting only solutions for 3C286
 
            from tab1 (but all fields from tab2 and tab3, indicated by
 
            no gainfield entry for these files).  Linear interpolation
 
            (in time) will be used for 'tab1' and 'tab3' (default); 'tab2' will
 
            use nearest.  For the 'tab2', the calibration spws map
 
            will be mapped to the data spws according to 0->0, 0->1, 2->2.
 
            (I.e., for data spw=0 and 2, the spw mapping is one to one,
 
            but data spw 1 will be calibrated by solutions from spw 0.) 
 
         
 
      gaincurve -- Apply internal VLA antenna gain curve correction (True/False)
 
              default: False;
 
              Use gaincurve=True ONLY for VLA data
 
      opacity -- Opacity correction to apply (nepers)
 
              default: 0.0 (no opacity correction)
 
              example: opacity=0.051
 
              Typical VLA values are: 5 GHz - 0.013, 8 GHz - 0.013
 
              15 GHz - 0.016, 23 GHz - 0.051, 43 GHz - 0.07
 
      parang -- If True, apply the parallactic angle correction.  FOR ANY
 
              POLARIZATION CALIBRATION AND IMAGING, parang = True
 
              default: False
 
      calwt -- Calibrate weights along with data for all
 
              relevant calibrations
 
              default: True; example: calwt=False
 
      async -- Run task in a separate process
 
                default: False; example: async=True
 
</pre>
 

Latest revision as of 19:24, 6 May 2015