% --- start of displayed preamble in the book --- input graph % --- end of displayed preamble in the book --- % graphic converted to gray in book using 'color2gray' defaultfont:="ptmr8r"; warningcheck:=0; beginfig(1) draw begingraph(2.5in,1.75in); gfill "yearw.dat" withcolor red; autogrid(grid.bot,itick.rt) withcolor .5white; frame.llft; endgraph; endfig; end;