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blcal Namespace Reference

Functions

def blcal

Function Documentation

def blcal.blcal (   vis = '',
  caltable = '',
  field = '',
  spw = '',
  intent = '',
  selectdata = True,
  timerange = '',
  uvrange = '',
  antenna = '',
  scan = '',
  observation = '',
  msselect = '',
  solint = 'inf',
  combine = 'scan',
  freqdep = False,
  calmode = 'ap',
  solnorm = False,
  gaintable = [''],
  gainfield = [''],
  interp = [''],
  spwmap = [],
  gaincurve = False,
  opacity = [],
  parang = False 
)
Calculate a baseline-based calibration solution (gain or bandpass)

This task determines a baseline by baseline gain (time) or bandpass (freq)
for all baseline pairs in the data set.   For the usual antenna-based calibration
of interferometric data, this task gaincal is recommended, even with only one
to three baselines.  For arrays with closure errors, use blcal

Keyword arguments:
vis -- Name of input visibility file
        default: none; example: vis='ngc5921.ms'
caltable -- Name of output Gain calibration table
        default: none; example: caltable='ngc5921.gcal'

       --- Data Selection (see help par.selectdata for more detailed information)

field -- Select field using field id(s) or field name(s).
          [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
       default: ''=all spectral windows and channels
       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
       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
       spw='0:0~10,1:20~30,2:1;2;3'; spw 0, channels 0-10,
                spw 1, channels 20-30, and spw 2, channels, 1,2 and 3
intent -- Select observing intent
          default: ''  (no selection by intent)
          intent='*BANDPASS*'  (selects data labelled with
                                BANDPASS intent)
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 kilo-lambda)
       default: '' (all); example:
       uvrange='0~1000kl'; uvrange from 0-1000 kilo-lamgda
       uvrange='>4kl';uvranges greater than 4 kilo lambda
       uvrange='0~1000km'; uvrange in kilometers
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 5
       antenna='5,6,10'; all baselines with antennas 5 and 6
scan -- Scan number range - New, under developement
observation -- Observation ID(s).
               default: '' = all
               example: '0~2,4'
msselect -- Optional complex data selection (ignore for now)

solint --  Solution interval (units optional) 
      default: 'inf' (~infinite, up to boundaries controlled by combine); 
      Options: 'inf' (~infinite), 'int' (per integration), any float
               or integer value with or without units
      examples: solint='1min'; solint='60s', solint=60 --> 1 minute
                solint='0s'; solint=0; solint='int' --> per integration
                solint-'-1s'; solint='inf' --> ~infinite, up to boundaries
                enforced by combine
combine -- Data axes to combine for solving
      default: 'scan' --> solutions will break at field and spw boundaries,
                but may extend over multiple scans (per field and spw) up
                to solint.
      Options: '','scan','spw',field', or any comma-separated combination
      example: combine='scan,spw'  --> extend solutions over scan boundaries
               (up to the solint), and combine spws for solving
freqdep -- Solve for frequency dependent solutions
       default: False (gain; True=bandpass); example: freqdep=True
calmode -- Type of solution
       default: 'ap' (amp and phase); example: calmode='p'
       Options: 'p','a','ap'
solnorm -- Normalize solutions.  For freqdep=F, this is a global (per-spw) 
           normalization of amplitudes (only).  For freqdep=T, each baseline 
           solution spectrum is separately normalized by its (complex) mean.
        default: False (no normalization)

gaintable -- Gain calibration table(s) to apply
       default: '' (none);
       examples: gaintable='ngc5921.gcal'
                 gaintable=['ngc5921.ampcal','ngc5921.phcal']
gainfield -- Select a subset of calibrators from gaintable(s)
       default:'' ==> all sources in table;
       'nearest' ==> nearest (on sky) available field in table
       otherwise, same syntax as field
       example: gainfield='0~3'
                gainfield=['0~3','4~6']
interp -- Interpolation type (in time[,freq]) to use for each gaintable.
         When frequency interpolation is relevant (B, Df, Xf),
         separate time-dependent and freq-dependent interp
         types with a comma (freq _after_ the comma).                
         Specifications for frequency are ignored when the
         calibration table has no channel-dependence.
         Time-dependent interp options ending in 'PD' enable a
         "phase delay" correction per spw for non-channel-dependent
         calibration types.
         default: '' --> 'linear,linear' for all gaintable(s)
         example: interp='nearest'   (in time, freq-dep will be
                                      linear, if relevant)
                  interp='linear,cubic'  (linear in time, cubic
                                          in freq)
                  interp=',spline'  (spline in freq; linear in
                                     time by default)
                  interp=['nearest,spline','linear']  (for multiple gaintables)
         Options: Time: 'nearest', 'linear'
                  Freq: 'nearest', 'linear', 'cubic', 'spline'
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]]
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), per spw
       default: [] (no opacity correction for any spw)
       examples:
           A global value for all spws:
             opacity=0.051
           Different values for spws 0,1,2:
             opacity=[0.051, 0.055, 0.057]
           (if more than 3 spws, spw 3 and higher will
            be assigned the last specified value, or 0.057)
       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 (required
       for polarization calibration)
       default: False

Definition at line 13 of file blcal.py.

References task_blcal.blcal(), and vla_uvfits_line_sf.verify.