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MX

        MX : Make and Clean maps from UV data

    This  task  combines UV_MAP and CLEAN in a single step.  The CLEAN algo-
    rithm is similar to the CLARK method, but with  major  cycles  operating
    directly  on  the ungridded UV table rather than in the image plane. Ac-
    cordingly, there is aliasing only of the residuals,  not  of  the  clean
    components.

    MX can process all planes of a data cube at the same time, but  a  sepa-
    rate list of component will be produced for each  plane.   The  cleaning
    cannot be restarted.

    The mapping process is identical to UV_MAP.  It makes a map from UV data
    by gridding the UV data using  a  convolving  function,  and  then  Fast
    Fourier  Transforming  the individual channels.  However, MX always pro-
    duces a single beam for all channels, thus neglecting  frequency  change
    between channels.

    MX  allows to shift the map center and rotate the image, by shifting the
    phase tracking center and rotating the UV coordinates of  the  input  UV
    table.

    MX  produces  several output maps, of name derived from MAP_NAME$, and a
    residual output UV table.


Gildas manager 2014-07-01