code: public void setup(PermutationGroup group, EquitablePartitionRefiner refiner) {
          this.bestExist = false;
          this.best = null;
          this.group = group;
          this.equitableRefiner = refiner;
      }
docs: Setup the group and refiner; it is important to call this method before
  calling {@link #refine} otherwise the refinement process will fail.
  
  @param group a group (possibly empty) of automorphisms
  @param refiner the equitable refiner