I used the Tikz to draw a directed graph. But the problem is the orientations are the end of edges. I need something like the following picture:
But my graph is in the following picture.
There are lots of ways, for example:
\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{arrows.meta}
\begin{document}
\begin{tikzpicture}
\foreach \a/\pos [count=\i] in {%
0/20,
-45/-25,
-90/-70,
-135/-115,
135/115} {
\draw[thick, -{Circle[open]}] (0, 0) -- (\a:20mm);
\node at (\pos:10mm) {$I_{\i}$};
}
\foreach \a/\direction in {0/<, -45/>, -90/<, -135/>, 135/<} {
\draw[thick, >={Stealth},-\direction] (0, 0) -- (\a:11mm);
}
\node[at=(current bounding box.south), below=2ex, inner sep=0pt]
{$I_1 - I_2 + I_3 - I_4 + I_5 = 0$};
\end{tikzpicture}
\end{document}
There should be a direct way of drawning it, but you can draw 2 paths :
\begin{tikzpicture}[thick]
\draw (0,0) -- (1,0);
\draw[<-] (1,0) node[above]{$I_1$} -- (2,0);
\end{tikzpicture}
Otherelse, you can use the [midway] option who write the node in the middle of the path.