flux, vf, x, y, vxy, major, vm, ratio, vr, phi, vp, type
Add a model component by hand to the tentative model.
EXAMPLE
-------

 0>mapunits arcsec
 0>addcmp 0.1, false, 0, 0, true, 0.3, true, 0.5, true

The above adds a gaussian component of flux fixed at 0.1 Jy, positioned
at the center of the current map but allowed to move during model fitting,
having a major axis of 0.3 arcseconds FWHM and an axial ratio of 0.5
both of which are allowed to vary during model fitting, and an implicit
major axis position angle of 0 degrees.

PARAMETERS
----------
flux  -  The integrated flux of the component, measured in Jy.
vf    -  If TRUE allow the flux to vary during model fitting.

x     -  The relative X-axis position of the component centroid in the
         current map units. (See help mapunits).
y     -  The relative Y-axis position of the component centroid in the
         current map units. (See help mapunits).
vxy   -  If TRUE allow x and y to vary during model fitting.

major -  The FWHM major axis of the elliptical aspect of the component
         measured in map units (See help mapunits).
vm    -  If TRUE allow major to vary during model fitting.

ratio -  The ratio of the minor axis to the major axis (0 -> 1).
vr    -  If TRUE allow the axial ratio to vary during model fitting.

phi   -  The Position angle of the major axis (degrees North -> East).
vp    -  If TRUE allow phi to vary during model fitting.

type  -  The component type. The default if not given is to assume
         that the component is a delta function unless a non-zero
         major axis has been provided.
         Valid types include:

                0 - Delta function.
                1 - Gaussian.
                2 - Uniformly bright disk.
                3 - Optically thin sphere.
                4 - Ring.

CONTEXT
-------
This command is provided mainly for use in automatic mapping scripts
where the normal interactive methods of adding model components (see
help mapplot and help edmodel) are inappropriate. In such contexts
this command can be used by a script to enter guesses at model
component characteristics and then use the modelfit command to
fit it to the data in order to parameterize maps after hands-off
mapping. Note that there are some restrictions on which parameters can
actually be fixed during modelfitting. These restrictions are silently
enforced by the modelfit command and you should acquaint yourself with
the modelfit help information before using this command seriously.

RELATED COMMANDS
----------------
mapplot  - (In the sense that it can be used to interactively add components).
edmodel  - Edit the current models in your favorite editor.
modelfit - Fit a variable image plane model to UV data.