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| Help on uvcontsub task:
| | {{uvcontsub}} |
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| Continuum fitting and subtraction in the uv plane
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| A polynomial of the desired order is fit to each baseline/time across the
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| specified channels that define the continuum emission. The data may
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| be averaged in time to increase the signal to noise. This fit
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| represents a uv-data model of the continuum across all channels.
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| For fitmode='subtract', the fitted continuum uv spectrum is
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| subtracted from all channels and the result (presumably only
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| line emission) is stored in the CORRECTED_DATA. The
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| continuum fit is stored in the MODEL_DATA.
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| For fitmode='model' the continuum model is stored in the
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| MODEL_DATA; but the CORRECTED_DATA is unaffected.
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| For fitmode='replace' the continuum model is stored in
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| the CORRECTED_DATA; this is useful to image the continuum model
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| result. You will have to rerun applycal to place the calibrated
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| data back in the CORRECTED_DATA
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| Keyword arguments:
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| vis -- Name of input visibility file
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| default: none; example: vis='ngc5921.ms'
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| field -- Field selection
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| default: field = '' means select all fields
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| field = 1 # will get field_id=1 (if you give it an
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| integer, it will retrieve the source with that index.
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| field = '1328+307' specifies source '1328+307'
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| field = '13*' will retrieve '1328+307' and any other fields
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| beginning with '13'
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| fitspw -- Selection of spectral windows and channels to use in the
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| fit for the continuum, using general spw syntax
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| default: ''=all; example: fitspw='0:5~30;40~55'
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| spw -- Optional per spectral window selection of channels from
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| which to subtract the continuum.
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| default: spw='', means subtract from all channels for
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| each spw that had a continuum estimated
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| Also, this specifies which spw/chan will be split
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| out if splitdata=True.
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| solint -- Timescale for per-baseline fit (units optional)
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| default: 'int' --> no averaging, fit every integration;
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| example: solint='10s' --> average to 10s before fitting
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| 10 or '10' --> '10s' (unitless: assumes seconds)
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| options: 'int' --> per integration
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| Keyword arguments:
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| vis -- Name of input visibility file
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| default: none; example: vis='ngc5921.ms'
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| field -- Field selection
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| default: field = '' means select all fields
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| field = 1 # will get field_id=1 (if you give it an
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| integer, it will retrieve the source with that index.
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| field = '1328+307' specifies source '1328+307'
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| field = '13*' will retrieve '1328+307' and any other fields
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| beginning with '13'
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| fitspw -- Selection of spectral windows and channels to use in the
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| fit for the continuum, using general spw syntax
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| default: ''=all; example: fitspw='0:5~30;40~55'
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| spw -- Optional per spectral window selection of channels from
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| which to subtract the continuum.
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| default: spw='', means subtract from all channels for
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| each spw that had a continuum estimated
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| Also, this specifies which spw/chan will be split
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| out if splitdata=True.
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| solint -- Timescale for per-baseline fit (units optional)
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| default: 'int' --> no averaging, fit every integration;
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| example: solint='10s' --> average to 10s before fitting
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| 10 or '10' --> '10s' (unitless: assumes seconds)
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| options: 'int' --> per integration
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| 'inf' --> per scan
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| fitorder -- Polynomial order for the fit of the continuum
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| default: 0 (constant); example: fitorder=1
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| fitmode -- Use of the continuum fit model
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| default: 'subtract'; example: fitmode='replace'
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| Options:
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| 'subtract'-store fitted continuum model in MODEL and
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| subtract this continuum from data in CORRECTED to
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| produce line-emission in CORRECTED.
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| 'model'-store fit continuum model in MODEL, but
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| do not change data in CORRECTED.
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| 'replace'-replace CORRECTED with continuum mode fit.
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| splitdata -- Split out continuum and continuum subtracted line data
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| default: 'False'; example: splitdata=True
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| The derived continuum data will be placed in: vis.cont
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| The continuum subtracted data will be placed in: vis.contsub
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| The spw/channels selected are given in spw
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| async -- Run task in a separate process (return CASA prompt)
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| default: False; example: async=True
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