Returns the restrictions which were used to generate the match.
optmatch_restrictions(obj)
Arguments
obj: An optmatch object
Returns
A list of min.controls, max.controls and either omit.fraction or mean.controls.
Details
If mean.controls was explicitly specified in the creation of the optmatch object, it is returned; otherwise omit.fraction is given.
Note that if the matching algorithm attempted to recover from initial infeasible restrictions, the output from this function may not be the same as the original function call.