![如何使用 TikZ 绘制这些图表?](https://linux22.com/image/434385/%E5%A6%82%E4%BD%95%E4%BD%BF%E7%94%A8%20TikZ%20%E7%BB%98%E5%88%B6%E8%BF%99%E4%BA%9B%E5%9B%BE%E8%A1%A8%EF%BC%9F.png)
答案1
这是实现此目的的方法。请随意自定义。
\documentclass[tikz,border=3.14mm]{standalone}
\usetikzlibrary{arrows.meta,decorations.pathreplacing,decorations.markings}
\tikzset{
mid arrow/.style={postaction={decorate,decoration={
markings,
mark=at position #1 with {\arrow{Stealth[scale=1.5]}}
}}},
dot/.style={circle,fill=black,inner sep=1.5pt}
}
\begin{document}
\begin{tikzpicture}[line width=1pt]
\draw (-4,0) -- (4,0) (0,-4) -- (0,4);
\draw[mid arrow=0.6] (3,0) to[out=90,in=0] node[midway,right=10pt]{$\gamma^+_R$} (0,2) node[dot,label=above right:{$iR$}]{};
\draw (0,2) to[out=180,in=90] (-2,1) node[left=10pt]{$\gamma^-_R$} ;
\draw[mid arrow=0.5] (-2,1) -- (-2,0) node[dot,label=below left:{\strut $-\delta(R)$}]{};
\draw[mid arrow=0.9] (-2,0) -- (-2,-1);
\draw (-2,-1) to[out=-90,in=180] (0,-2) node[dot,label=below right:{$-iR$}]{};
\draw[mid arrow=0.5] (0,-2) to[out=0,in=-90] (3,0);
\node[dot,label=below:{\strut $-\delta_1$}] at (-1,0){};
\node at (3,-3) {$\gamma_R=\gamma^+_R+\gamma^-_R$};
\end{tikzpicture}
\end{document}