%% 
%%  A DANTE-Edition example
%% 
%%  Example 36-00-48 on page 787.
%% 
%%  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.
%% 
%% 
%% ==== 
% Show page(s) 1
%% 
\documentclass[]{article}
\pagestyle{empty}
\setlength\textwidth{375.57637pt}
\setlength\parindent{0pt}

\usepackage{pstricks,multido}
\definecolorseries{testA}{rgb}{last}{blue}{yellow}
\resetcolorseries[300]{testA}%  defines the series with 200 colors


\begin{document}
\psset{unit=1bp,linewidth=1.2pt}
\begin{pspicture}(300,50)
  \multido{\nC=1+1}{300}{%
    \psline[linecolor={testA!![\nC]}](\nC,0)(\nC,50)}
\end{pspicture}
\end{document}