\input{preamble-standalone.ltx}
\begin{document}

% Ex. No. 98 (Section 14.1.1 : Example)

\begin{tikzpicture}
  \tkzInit[xmax=6]
  \tkzDrawX
  \tkzHTick[mark=ball,mark size=3pt]{pi/2}
  \tkzHTick[mark=*,
     mark options={color=purple}]{2*exp(1)}
\end{tikzpicture}

\end{document}