code: public SDVariable unsortedSegmentSum(String name, @NonNull SDVariable data, @NonNull SDVariable segmentIds, int numSegments) {
          validateNumerical("unsortedSegmentSum", "data", data);
          validateInteger("unsortedSegmentSum", "segmentIds", segmentIds);
          SDVariable ret = f().unsortedSegmentSum(data, segmentIds, numSegments);
          return updateVariableNameAndReference(ret, name);
      }
docs: Unsorted segment sum operation. As per {@link #segmentSum(String, SDVariable, SDVariable)} but without
  the requirement for the indices to be sorted.<br>
  If data =     [1, 3, 2, 6, 4, 9, 8]<br>
  segmentIds =  [1, 0, 2, 0, 1, 1, 2]<br>
  then output = [9, 14, 10] = [sum(3,6), sum(1,4,9), sum(2,8)]<br>
  
  @param name        Name of the output variable
  @param data        Data (variable) to perform unsorted segment sum on
  @param segmentIds  Variable for the segment IDs
  @param numSegments Number of segments
  @return Unsorted segment sum output