\listfiles\errorcontextlines=100
\documentclass{article}

%\usepackage{fp}
%\input{multido}
\usepackage{multido}[2004/05/15]
\usepackage{fp}

\begin{document}

\typeout{\meaning\FPadd}
\typeout{\meaning\FPsub}
\typeout{\meaning\fpAdd}
\typeout{\meaning\fpSub}

\setlength{\unitlength}{1cm}

\begin{picture}(8,1)(0,-.5)
  \small
  \put(0,0){\vector(1,0){8}}
  \multido{\i=0+1,\n=0+0.25}{8}{%
    \put(\i,-.1){\line(0,1){.2}}
    \put(\i,-.2){\makebox(0,0)[t]{\n}}}
\end{picture}

\end{document}