All Implemented Interfaces:
IPenDatasource, EventListener, ChangeListener

public class SumDiffPenDatasource extends AbstractFunctionPenDatasource
Filename - SumPensDatasource Author: Perry Arellano-Jones Year: 2014

This datasource adds or subtracts the value of two pens and returns a dataset of the result. It requires two pens to be specified, a 'driving' Pen and a 'secondary' pen. Results are derived by adding to or subtracting from to the driving Pen. Utilizes the PenAttribute#FUNCTION_PARAM to determine whether summation or negation is done on the driving pen.