带有虚线的正方形，箭头方向相反或相同

Question

我想要绘制下图中的一个正方形：

我想知道如何反转这个粗体箭头。

提前致谢！

Answer 1

这不是最优雅的中途箭头方法，但你可以用普通的 来实现tikz。（更好的箭头方法在TikZ：如何在线中间画箭头？以了解更复杂的数据。）

\documentclass{article}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
\draw [thick] (3,0) -- (0,0) -- (0,3);
\draw [thick,  latex reversed-] (0,3)--(0,5)--(3,5);
\draw [thick, latex reversed-latex reversed] (3,5) -- (6,5) -- (6,3);
\draw [thick, -latex reversed] (6,3) -- (6,0) -- (3,0);
\draw [dashed] (0,2.5) -- (6,2.5) node [above, pos=.5] {c};
\node [draw=none, anchor=east] at (0,2.5) {3};
\node [draw=none, anchor=west] at (6,2.5) {4};
\node [draw=none, anchor=east] at (0,3) {a};
\node [draw=none, anchor=west] at (6,3) {a};
\node [draw=none, anchor=east] at (0,0) {5};
\node [draw=none, anchor=east] at (0,5) {1};
\node [draw=none, anchor=west] at (6,0) {6};
\node [draw=none, anchor=west] at (6,5) {2};
\node [draw=none, anchor=south] at (3,5) {b};
\node [draw=none, anchor=north] at (3,0) {b};
\end{tikzpicture}

\begin{tikzpicture}
\draw [thick] (3,0) -- (0,0) -- (0,3);
\draw [thick,  latex reversed-] (0,3)--(0,5)--(3,5);
\draw [thick, latex reversed-] (3,5) -- (6,5) -- (6,3);
\draw [thick, latex reversed-latex reversed] (6,3) -- (6,0) -- (3,0);
\draw [dashed] (0,2.5) -- (6,2.5) node [above, pos=.5] {c};
\node [draw=none, anchor=east] at (0,2.5) {$3'$};
\node [draw=none, anchor=west] at (6,2.5) {$4'$};
\node [draw=none, anchor=east] at (0,3) {a};
\node [draw=none, anchor=west] at (6,3) {a};
\node [draw=none, anchor=east] at (0,0) {$5'$};
\node [draw=none, anchor=east] at (0,5) {$1'$};
\node [draw=none, anchor=west] at (6,0) {$6'$};
\node [draw=none, anchor=west] at (6,5) {$2'$};
\node [draw=none, anchor=south] at (3,5) {b};
\node [draw=none, anchor=north] at (3,0) {b};
\end{tikzpicture}
\end{document}