Applycal
From CASA Guides
Help on applycal task:
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
