Basic Information on pcsub

Task: pcsub
Purpose: Subtract a plane (optional by polynomial fit) from a cube
Categories: map combination

        PCSUB (Polynomial Continuum Subtraction) is a MIRIAD task that
        does a polynomial least squares fit to selected planes of a cube
        to make a continuum map that can be subtracted from the input
        cube.  Alternatively, if a continuum map is already known, this
        can be subtracted.
 
        Limitations:
         1) only designed for 3-D images
         2) the region input parameter should be specified only
            with the IMAGE command, e.g.,
 
            region=image(1,5),image(125,128)
 
            would average and subtract planes 1:5 and 125:128
            any specified x-y sub-regions will be ignored
         3) Blanked pixels in the image are only partially handled.
            If a plane is completely blank then it is ignored, however,
            a plane that is partially blanked is not dealt with.
         4) No fit to a polynomial greater than 10 is permitted.
 

Key: in
        The input image dataset. No default.

Key: out
        The output image.  For default see cont= keyword.

Key: order
        The order of the highest term of the polynomial fit.
        Default is 0, i.e. a constant.

Key: region
        Specify the channels to fit with a command of the region of
        interest format, e.g.
          region=image(1,5),image(120,128)
        This would fit and subtract channels 1:5 and 120:128 from the
        cube.  Note that blanked planes are correctly ignored, but
        isolated blanked pixels in a plane are not.

Key: cont
        If out is provided, the continuum is generated from the region
        (channels) selected.  This continuum (cont=) is subtracted from
        each of the channels of the cube (in=) to yield an output cube
        (out=).
        If out alone is provided, this is all that occurs.
        If "cont" is also provided, the continuum map is also written to
        the file specified, if that file did not exist yet.
        If "cont" did already exist, it is assumed to be the continuum
        map, and subtracted from the input cube.
        If "cont" alone is provided, ONLY the continuum map is written,
        no output cube is written.
 
Revision: 1.5, 2013/08/30 01:49:21 UTC