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uvcontsub_pg.uvcontsub_pg_ Class Reference

List of all members.

Public Member Functions

def __init__
def __call__

Private Attributes

 __bases__
 __doc__

Static Private Attributes

string __name__

Detailed Description

Definition at line 18 of file uvcontsub_pg.py.


Constructor & Destructor Documentation

Definition at line 21 of file uvcontsub_pg.py.


Member Function Documentation

def uvcontsub_pg.uvcontsub_pg_.__call__ (   self,
  vis = None,
  field = None,
  fitspw = None,
  combine = None,
  solint = None,
  fitorder = None,
  spw = None,
  want_cont = None,
  async = None 
)
Continuum fitting and subtraction in the uv plane

Continuum fitting and subtraction in the uv plane:

This task estimates the continuum emission by fitting polynomials to
the real and imaginary parts of the spectral windows and channels
selected by fitspw.  This fit represents a model of the continuum in 
all channels.

The fitted continuum spectrum is subtracted from all channels 
selected in spw, and the result (presumably only line emission)
is stored in a new MS (vis + ".contsub").
It will read from the CORRECTED_DATA column of vis if it is present,
or DATA if it is not.  Whichever column is read is presumed to have
already been calibrated.

If want_cont is True, the continuum fit is placed in a second new MS
(vis + '.cont').  N.B. because the continuum model is necessarily a
smoothed fit, images made with it are liable to have their field of
view reduced in some strange way.  Images of the continuum should be
made by simply excluding the line channels (and probably averaging the
remaining ones) in clean.

Keyword arguments:
vis -- Name of input visibility file
default: none; example: vis='ngc5921.ms'
field -- Field selection for continuum estimation and subtraction.
 The estimation and subtraction is done for each selected field
 in turn.  (Run listobs to get lists of the ID and names.)
default: field = '' means select all fields
field = 1 # will get field_id=1 (if you give it an 
        integer, it will retrieve the source with that index.
field = '1328+307'  specifies source '1328+307'
field = '13*' will retrieve '1328+307' and any other fields
   beginning with '13'
fitspw -- Selection of spectral windows and channels to use in the
  fit for the continuum, using general spw:chan syntax.
  See the note under combine.
default: '' (all)
example: fitspw='0:5~30;40~55'
combine -- Data axes to combine for the continuum estimate.
It must include 'spw' if spw contains spws that are not in
fitspw!
default: '' --> solutions will break at scan, field, and spw
      boundaries according to solint
      Options: '', 'spw'', 'scan', or 'spw, scan'
      example: combine='spw' --> form spw-merged continuum estimate
solint -- Timescale for per-baseline fit (units optional)
default (recommended): 'int' --> no time averaging, do a
                       fit for each integration and let the
                       noisy fits average out in the image.

example: solint='10s'  --> average to 10s before fitting
         10 or '10' --> '10s' (unitless: assumes seconds)
options: 'int' --> per integration
         'inf' --> per scan

If solint is longer than 'int', the continuum estimate can be
corrupted by time smearing!

fitorder -- Polynomial order for the fits of the continuum w.r.t.
    frequency.  fitorders > 1 are strongly discouraged
    because high order polynomials have more flexibility, may
    absorb line emission, and tend go wild at the edges of
    fitspw, which is not what you want.

default: 0 (constant); example: fitorder=1

spw -- Optional per spectral window selection of channels to include
       in the output.  See the note under combine.

       The spectral windows will be renumbered to start from 0, as in
       split.
want_cont -- Create vis + '.cont' to hold the continuum estimate.
default: 'False'; example: want_cont=True
The continuum estimate will be placed in vis + '.cont'
async -- Run task in a separate process (return CASA prompt)
default: False; example: async=True

Definition at line 26 of file uvcontsub_pg.py.

References vla_uvfits_line_sf.verify.


Member Data Documentation

Definition at line 22 of file uvcontsub_pg.py.

Definition at line 23 of file uvcontsub_pg.py.

string uvcontsub_pg.uvcontsub_pg_.__name__ [static, private]

Definition at line 19 of file uvcontsub_pg.py.


The documentation for this class was generated from the following file: