The class group is computed if it has not been already. The class group is computed if it has not been already. The class group is computed if it has not been already. The class group and a set of generators are computed if they have not been already. At present, this function is only implemented for imaginary orders.
Input consists of reading a bigint value for the discriminant.
The discriminant is always displayed, while the other invariants are displayed only if they have been computed.