name of stan sub object from stanfit to use for calculations.
calc
string containing R calculation to evaluate, with the string 'object' in place of the actual object name.
objectindices
matrix of indices, with the number of columns matching
the number of dimensions of the object. 'all' computes which( array(1,objdims)==1,arr.ind=TRUE),
where objdims is what would be returned by dim(object) if the object existed in the R environment.
summary
if FALSE, a iterations * parameters matrix is returned, if TRUE,
rstan::monitor is first run on the output.
Value
matrix of values of the specified interactions at each iteration.