15.8.12  Example 

     TD:ADD 1 TO 2
          or...
     TD:ADD 2 1
          or...
     TD:ADD TO 2 1
Data set 1 is added to data set 2.  Data set 1 is unchanged.
     TD:ADD 1 TO 2 APPEND
Data  set 1 and 2 are added.  The result in put into a new data set.  Both
sets 1 and 2 are unchanged.
     TD:SUBTRACT 1 FROM 2
Data set 1 is subtracted from data set 2.  Data set 1 is unchanged.
See:Command DIVIDE,MULTIPLY