simplify.formula rewrites a formula using shorthand notation.
Currently only the factor crossing operator * is applied, so that
expanded expression such as a+b+a:b becomes a*b.
expand.formula does the opposite, additionally expanding other
expressions, i.e. all nesting (/), grouping and ^.
Usage
simplify.formula(x)
expand.formula(x)
Arguments
x
a formula or an object from which it can be extracted (such as
a fitted model object).