code: @Override
      public Object getMember(String name) {
          switch (name) {
              case "size":
                  return F_size;
              case "toArray":
                  return F_toArray;
              case "equals":
                  return F_equals;
              case "hashCode":
                  return F_hashCode;
              case "apply":
                  return F_apply;
              case "copy":
                  return F_copy;
  //            case "foreachActive":
  //                return F_foreachActive;
              case "numActives":
                  return F_numActives;
              case "numNonzeros":
                  return F_numNonzeros;
              case "toSparse":
                  return F_toSparse;
              case "toDense":
                  return F_toDense;
              case "compressed":
                  return F_compressed;
              case "argmax":
                  return F_argmax;
  
          }
          return super.getMember(name);
      }
docs: get the value of that named property