.literalGRAPH Design MethodologyBThe design of GRAPH follows the design of sample routine XGFUNC. ?GRAPH calls XGDATA which in turn calls GRUSER. GRUSER has fivemodes which are defined below. Mode definitions:- 1) No initialization done in the first step.1 2) Initialize scaling factors by calling XGVDEF.K 3) Print a sequence of returned data. Converting to print units as we go. 4) End of sequence.  requested. 5) End of task..EL