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| − | <pre>
| + | {{uvcontsub}} |
| − | Help on uvcontsub task:
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| − | Continuum fitting and subtraction in the uv plane
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| − | | |
| − |
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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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| − |
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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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| − | </pre>
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