Add a component to the current model.
XSPEC> addcomp <comp #> <comp>
where <comp #> is the position in the model specification for the component and <comp> is its name. The user is prompted for parameter values for the component. Whenever it makes sense, XSPEC attempts to associate the component with the additive group of the component after it (see the model command for a description of additive groups). If you specify the component to be the last component in the model, then XSPEC will attempt to associate it with the overall multiplicative group. If it does not make sense to associated the component with an additive group, a new additive group is created.