code: public SwaptionDataLattice append(SwaptionDataLattice other, AnalyticModel model) {
  
  		SwaptionDataLattice combined = new SwaptionDataLattice(referenceDate, quotingConvention, displacement,
  				forwardCurveName, discountCurveName, floatMetaSchedule, fixMetaSchedule);
  		combined.entryMap.putAll(entryMap);
  
  		if(quotingConvention == other.quotingConvention && displacement == other.displacement) {
  			combined.entryMap.putAll(other.entryMap);
  		} else {
  			SwaptionDataLattice converted = other.convertLattice(quotingConvention, displacement, model);
  			combined.entryMap.putAll(converted.entryMap);
  		}
  
  		return combined;
  	}
docs: Append the data of another lattice to this lattice. If the other lattice follows a different quoting convention, it is automatically converted.
  However, this method does not check, whether the two lattices are aligned in terms of reference date, curve names and meta schedules.
  If the two lattices have shared data points, the data from this lattice will be overwritten.
  
  @param other The lattice containing the data to be appended.
  @param model The model to use for context, in case the other lattice follows a different convention.
  
  @return The lattice with the combined swaption entries.