%% 
%%  The LaTeX Graphics Companion, 2ed (first printing May 2007)
%% 
%%  Example 11-2-20 on page 735.
%% 
%%  Copyright (C) 2007 Michel Goossens, Frank Mittelbach, Denis Roegel, Sebastian Rahtz, Herbert Vo\ss 
%% 
%%  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.
%% 

\documentclass{ttctexa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{159.83385pt}

\StartShownPreambleCommands
\usepackage{xcolor,multido}
\definecolorseries{testA}
  {rgb}{last}{black}{white}
\resetcolorseries[200]{testA}% series of 200 col
\linethickness{0.005\linewidth}
\StopShownPreambleCommands
\begin{document}
\noindent
\multido{\nC=1+1}{200}{\color{testA!![\nC]}%
  \line(0,1){50}\hspace{0.005\linewidth}}
\end{document}
