Imcontsub

Help on imcontsub task:

Subtracts specified continuum channels from a spectral line data set

        For a spectral line image, the regions to determine the continuum
        regions are first defined.  A graphical interface 'regions' is
        the most versatile method of selecting the line-free regions.  For
        a multi-spw image, the chanellization must be the same for all.

        The continuum channels are specified and two output images are made: a
        continuum image and a continuum-subtracted spectral line image.

        The continuum subtraction can be applied to either the whole image
        (default) or a selected regions.  Regions are specified via
        the box,chans, and stokes parameters or with a region file
        given by the region parameter.

        Keyword arguments:
        imagename -- Input spectral line image
                Default: none; Example: imagename='ngc5921_task.im'
        linefile -- Name of output line image
                Default: none; Example: outline='ngc5921_line.im'
        contfile -- Name of output continuum image
                Default: none; Example: contfile='ngc5921_cont.im'
        fitorder -- Polynomial order for the continuum estimation.
                Default: 0; Example fitorder=2
        region -- ImageRegion file to define continuum
                Default: ''; none
                Example: region='myimage.im.rgn'
                         region='region1'
                Use the viewer on the image cube to define the continuum,
                   regions.  More general than box/chans.  Still experimental
                to retrieve the list of names.
        box --  A box region on the directional plane
                ONLY pixel values acceptable at this time.
                Default: none (whole 2-D plane); Example: box='10,10,50,50'
        chans -- channel numbers go select for the continuum,
                ONLY channel numbers accepted at this time.
                Default: none (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', ...