UV_FIT

        UV_FIT :  Fit point and centro-symmetric models to a UV table

    This task allows fitting of models directly from the  visibilities.  The
    models  are  either  simple or linear combinations of several functions.
    The results of the fitting process are the position offsets in R.A.  and
    Dec  (arc  seconds) of the model source from the phase reference center,
    and its flux (Janskys).  Depending on the fitting  functions  additional
    fit   results   are  possible.  Currently  supported  distributions  and
    additional fit parameters are:

    POINT     Point source              : None
    E_GAUSS   Elliptic Gaussian source  : FWHP Axis (Major and Minor), Pos Ang
    C_GAUSS   Circular Gaussian source  : FWHP Axis
    C_DISK    Circular Disk             : Diameter
    E_DISK    Elliptical (inclined) Disk: Axis (Major and Minor), Pos Ang
    RING      Annulus                   : Diameter (Inner and Outer)
    EXPO      Exponential brightness    : FWHP Axis
    POWER-2   B = 1/r^2                 : FWHP Axis
    POWER-3   B = 1/r^3                 : FWHP Axis