imcontsub.py

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#
# This file was generated using xslt from its XML file
#
# Copyright 2009, Associated Universities Inc., Washington DC
#
import sys
import os
from  casac import *
import string
from taskinit import casalog
#from taskmanager import tm
import task_imcontsub
def imcontsub(imagename='', linefile='', contfile='', fitorder=0, region='', box='', chans='', stokes=''):

        """Estimates and subtracts continuum emission from an image cube

  For each (x, y) column in imagename (or a subset selected by region and/or
  box), this estimates the continuum by fitting a polynomial to one or more
  subsets of the channels.  The continuum estimate is saved in contfile, and
  subtracted from imagename (or its subset) to make a spectral line estimate,
  which is saved in linefile.

  
  

  Keyword arguments:
  imagename -- Input image cube
    Default: none; Example: imagename='ngc5921_task.im'
  linefile -- Name of output spectral line cube
    Default: none; Example: outline='ngc5921_line.im'
  contfile -- Name of output continuum cube
    Default: none; Example: contfile='ngc5921_cont.im'
  fitorder -- Polynomial order for the continuum estimation.
    Default: 0; Example fitorder=2
  region -- ImageRegion file to select a portion of the cube for output.
    Default: '' (= everything)
    Example: region='myimage.im.rgn'
             region='region1'
    Use the viewer on the image cube to define the continuum
    regions.  This is more general than box but still experimental.
    N.B. This is NOT for selecting a subset of the input for
         fitting the continuum!  Only pixels that are in region
         will be considered, however.

  box --  A [blcx, blcy, trcx, trcy] region on the directional plane for
          selecting a subset for output.
          ONLY pixel values are acceptable at this time.
          Default: none (whole 2-D plane); Example: box='10,10,50,50'
          N.B. This is NOT for selecting a subset of the input for
               fitting the continuum!  Only pixels that are in region
               will be considered, however.
  chans -- line-free channel numbers to fit the continuum to.
           N.B.: This is currently the _only_ way to specify what is
                 continuum vs. line emission.
           ONLY channel numbers accepted at this time, i.e. there is no
           'spw:' as in the spw parameter of other tasks.  For
           a multi-spw image, the channelization must be the same for all.
           Default: '' (all)
           Example: chans='3~6;>40'
  stokes -- Stokes parameters to image, may or may not be separated
            by commas but best if you use commas.
            Default: none (all); Example: stokes='IQUV';
            Options: 'I','Q','U','V','RR','RL','LR','LL','XX','YX','XY','YY', ... 



        """

#
#    The following is work around to avoid a bug with current python translation
#
        mytmp = {}

        mytmp['imagename'] = imagename
        mytmp['linefile'] = linefile
        mytmp['contfile'] = contfile
        mytmp['fitorder'] = fitorder
        mytmp['region'] = region
        mytmp['box'] = box
        mytmp['chans'] = chans
        mytmp['stokes'] = stokes
        pathname='file:///'+os.environ.get('CASAPATH').split()[0]+'/share/xml/'
        trec = casac.utils().torecord(pathname+'imcontsub.xml')

        casalog.origin('imcontsub')
        if trec.has_key('imcontsub') and casac.utils().verify(mytmp, trec['imcontsub']) :
            result = task_imcontsub.imcontsub(imagename, linefile, contfile, fitorder, region, box, chans, stokes)

        else :
          result = False
        return result