@Override
 public void getInfo(Assignment<V, T> assignment, Model<V, T> model, Map<String, String> info) {
   if (model.variablesWithInitialValue().size() > 0)
     info.put(
         "Perturbations: Total penalty",
         sDoubleFormat.format(getPerturbationPenalty(assignment, model)));
 }
 @Override
 public double getPerturbationPenalty(Assignment<V, T> assignment, Model<V, T> model) {
   double penalty = 0.0;
   for (V variable : model.variablesWithInitialValue()) {
     T value = assignment.getValue(variable);
     if (value != null
         && variable.getInitialAssignment() != null
         && !value.equals(variable.getInitialAssignment()))
       penalty += getPenaltyD(assignment, value, variable.getInitialAssignment());
   }
   return penalty;
 }