% --- start of displayed preamble in the book --- % --- end of displayed preamble in the book --- defaultfont:="ptmr8r"; warningcheck:=0; beginfig(1) input graph path m; numeric n,width; width:=20; defaultscale:=0.6; n:=0; def bar(expr name,value,r,g,b) = path q; q:=(n,0)--(n,value)-- (n+width,value)--(n+width,0)--cycle; gfill q withcolor (r,g,b); gdraw q; picture p; p = name infont defaultfont scaled defaultscale rotated 90; glabel.rt(image(unfill bbox p; draw p),(n,10)); n:=n+width; enddef; draw begingraph(2.4in,1.75in); setrange((0,0),(11*width,100)); drawoptions(withcolor red); autogrid(,otick.lft); drawoptions(); gdata ("chap.dat",c, bar(c1,(scantokens c2), (scantokens c3),(scantokens c4),(scantokens c5));); endgraph; endfig; end;