\input{preamble-standalone.ltx} \begin{document} % Ex. No. 100 (Section 14.2.1 : Place an arrow on segment) \begin{tikzpicture} \tikzset{ arr/.style={postaction=decorate, decoration={markings, mark=at position .5 with {\arrow[thick]{#1}} }}} \tkzDefPoint(0,0){A} \tkzDefPoint(4,-4){B} \tkzDrawSegments[arr=stealth](A,B) \tkzDrawPoints(A,B) \end{tikzpicture} \end{document}