/* ** (C) Copyright 1999 Gary King ** All Rights Reserved. ** http://GKing.Harvard.Edu, King@Harvard.Edu ** ** add a set of lines to a graph ** ** call plines(x,y); ** ** for globals, see pline() */ proc 0=plines(x,y); if rows(x)<2 or rows(y)<2 or rows(x)/=rows(y); errorlog "plines: input error"; stop; endif; pline(trimr(lag(x),1,0),trimr(lag(y),1,0),trimr(x,1,0),trimr(y,1,0)); endp;