%% 
%%  Ein Beispiel der DANTE-Edition
%%  
%%  1. Auflage
%% 
%%  Beispiel 15-02-43 auf Seite 755.
%% 
%%  Copyright (C) 2011 Herbert Voss
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%% 
%%  See http://www.latex-project.org/lppl.txt for details.
%% 
%% 
%% ==== 
verbatimtex
%% 
\documentclass[]{article}
\usepackage[T1]{fontenc}
\begin{document}
etex
% --- start of displayed preamble in the book ---
input graph; input sarith;
% --- end of displayed preamble in the book ---
beginfig(1)
draw
begingraph(8cm,6cm)
  gdata("data/mp/data2-mp.dat", v, path p;
    augment p(v1 Ssub "0.5",0); augment p(v1 Ssub "0.5",v2);
    augment p(v1 Sadd "0.5",v2);augment p(v1 Sadd "0.5",0);
    gfill p--cycle withcolor 0.8white; gdraw p--cycle; );
  gdraw "data/mp/data3-mp.dat" withcolor blue withpen pencircle scaled 2bp;
    gdraw "data/mp/data4-mp.dat" dashed evenly withpen pencircle scaled 2bp;
endgraph;
endfig;
end;
\end{document}