# tikz arrow heads in both ends [duplicate]

\documentclass[tikz]{standalone}

\begin{document}

\begin{tikzpicture}
\draw [-] (0, 0) edge node[above] {$\epsilon_f$} (5, 0);
\draw [<->] (1, -1) edge node[below] {$\epsilon_f$} (4, -1);
\end{tikzpicture}

\end{document}


The result is :

Why does the left-end has strange arrowhead? How can I make it a normal <- arrowhead?

## marked as duplicate by marmot, CarLaTeX, Mensch, Stefan Pinnow, Phelype OleinikJan 21 at 19:50

• Those are actually two arrowheads pointing to the same spot, though I wouldn't know why the other one is drawn. Note that this also won't happen if you use to or -- instead of edge. – Circumscribe Jan 21 at 16:34

\documentclass[tikz]{standalone}
\draw [-] (0, 0) edge node[above] {$\epsilon_f$} (5, 0);
\draw  (1, -1) edge[<->] node[below] {$\epsilon_f$} (4, -1);