void createVarTypes(int ins, int outs)
   {
      assert ins > 0 && outs > 0;
      inVarTypes = new Class[ins];
      outVarTypes = new Class[outs];

      for (int i = 0; i < ins; i++)
      {
         inVarTypes[i] = parameterTypes[INPUT_FIX_PARAMETERS + i];
      }
      int offset = INPUT_FIX_PARAMETERS + ins + optionTypes.length
            + OUTPUT_FIX_PARAMETERS;
      for (int i = 0; i < outs; i++)
      {
         outVarTypes[i] = parameterTypes[offset + i];
      }
   }