我不知道为什么，但是最后四个命令（\draw[ultra thick...）在以下代码中不起作用（它们将图形移动到页面的左侧）。
\begin{figure}[H]
\begin{center}
\begin{tikzpicture}[scale=1.25]
\draw[thick,->] (0,-2.5) -- (0,2.5);
\draw[thick,->] (-2.5,0) -- (2.5,0);
\draw[ultra thick] ([shift=(-157:0.75)] 2, 1.5) arc (-157:150.5:0.75cm);
\draw[ultra thick] ([shift=(65:0.75)] -1, 0.5) arc (65:405:0.75cm);
\draw[ultra thick] ([shift=(-150:1.25)] 2, 1.5) arc (-150:180:1.25cm);
\draw[ultra thick] ([shift=(13:1.25)] -1, 0.5) arc (13:365:1.25cm);
\draw[ultra thick] (1.36,1.88) -- (-0.7,1.18);
\draw[ultra thick] (-0.47,1.03) -- (0.77,1.47);
\draw[ultra thick] (0.20,0.80) -- (1.33,1.22);
\draw[ultra thick] (0.24,0.60) -- (0.94,0.87);
\draw[ultra thick, postaction={decorate},decoration={
markings,
mark=at position 0.5 with {\arrow{latex[length=0.3cm]}}}] (1.36,1.88) --
(-0.7,1.18);
\draw[ultra thick, postaction={decorate},decoration={
markings,
mark=at position 0.75 with {\arrow{latex[length=0.3cm]}}}] (-0.47,1.03)
-- (0.77,1.47);
\draw[ultra thick, postaction={decorate},decoration={
markings,
mark=at position 0.75 with {\arrow{latex[length=0.3cm]}}}] (0.20,0.80)
-- (1.33,1.22);
\draw[ultra thick, postaction={decorate},decoration={
markings,
mark=at position 0.25 with {\arrowreversed{latex[length=0.3cm]}}}]
(0.24,0.60) -- (0.94,0.87);
\draw[fill] (-0.47,1.03) circle (0.04);
\draw[fill] (0.24,0.60) circle (0.04);
\draw[fill] (1.36,1.89) circle (0.04);
\draw[fill] (-0.7,1.19) circle (0.04);
\draw[fill] (0.21,0.81) circle (0.04);
\draw[fill] (1.30,1.21) circle (0.04);
\draw[fill] (0.92,0.86) circle (0.04);
\draw[fill] (0.75,1.47) circle (0.04);
\node at (-1,0.5) {$\times$};
\node at (-1,0.3) {$r_{2}$};
\node at (2,1.5) {$\times$};
\node at (2,1.3) {$r_{1}$};
\draw[ultra thick,{latex[length=0.3cm, bend]}-]($(135,0.75)+(2,1.5)$)
arc (135:90:0.75);
\draw[ultra thick,{latex[length=0.3cm, bend]}-]($(135,1.25)+(2,1.5)$)
arc (135:90:1.25);
\draw[ultra thick,-{latex[length=0.3cm, bend]}]($(270,0.75)+(-1,0.5)$)
arc (270:315:0.75);
\draw[ultra thick,-{latex[length=0.3cm, bend]}]($(270,1.25)+(-1,0.5)$)
arc (270:315:1.25);
\end{tikzpicture}
\end{center}
\caption{Pochhammer contour, another path used for the integral
representation of confluent hypergeometric functions}
\end{figure}
答案1
好吧，下面的坐标写成笛卡尔坐标，但可能应该是极坐标。我还强调这不是 Pochhammer 轮廓。单值化不会取消，但它们会相加。
\documentclass[tikz, border=3.14pt]{standalone}
\usetikzlibrary{decorations.markings,arrows.meta,bending,calc}
\begin{document}
\begin{tikzpicture}[scale=1.25]
\draw[thick,->] (0,-2.5) -- (0,2.5);
\draw[thick,->] (-2.5,0) -- (2.5,0);
\draw[ultra thick] ([shift=(-157:0.75)] 2, 1.5) arc (-157:150.5:0.75cm);
\draw[ultra thick] ([shift=(65:0.75)] -1, 0.5) arc (65:405:0.75cm);
\draw[ultra thick] ([shift=(-150:1.25)] 2, 1.5) arc (-150:180:1.25cm);
\draw[ultra thick] ([shift=(13:1.25)] -1, 0.5) arc (13:365:1.25cm);
\draw[ultra thick] (1.36,1.88) -- (-0.7,1.18);
\draw[ultra thick] (-0.47,1.03) -- (0.77,1.47);
\draw[ultra thick] (0.20,0.80) -- (1.33,1.22);
\draw[ultra thick] (0.24,0.60) -- (0.94,0.87);
\draw[ultra thick, postaction={decorate},decoration={
markings,
mark=at position 0.5 with {\arrow{latex[length=0.3cm]}}}] (1.36,1.88) --
(-0.7,1.18);
\draw[ultra thick, postaction={decorate},decoration={
markings,
mark=at position 0.75 with {\arrow{latex[length=0.3cm]}}}] (-0.47,1.03)
-- (0.77,1.47);
\draw[ultra thick, postaction={decorate},decoration={
markings,
mark=at position 0.75 with {\arrow{latex[length=0.3cm]}}}] (0.20,0.80)
-- (1.33,1.22);
\draw[ultra thick, postaction={decorate},decoration={
markings,
mark=at position 0.25 with {\arrowreversed{latex[length=0.3cm]}}}]
(0.24,0.60) -- (0.94,0.87);
\draw[fill] (-0.47,1.03) circle (0.04);
\draw[fill] (0.24,0.60) circle (0.04);
\draw[fill] (1.36,1.89) circle (0.04);
\draw[fill] (-0.7,1.19) circle (0.04);
\draw[fill] (0.21,0.81) circle (0.04);
\draw[fill] (1.30,1.21) circle (0.04);
\draw[fill] (0.92,0.86) circle (0.04);
\draw[fill] (0.75,1.47) circle (0.04);
\node at (-1,0.5) {$\times$};
\node at (-1,0.3) {$r_{2}$};
\node at (2,1.5) {$\times$};
\node at (2,1.3) {$r_{1}$};
\draw[ultra thick,{latex[length=0.3cm, bend]}-]($(135:0.75)+(2,1.5)$)
arc (135:90:0.75);
\draw[ultra thick,{latex[length=0.3cm, bend]}-]($(135:1.25)+(2,1.5)$)
arc (135:90:1.25);
\draw[ultra thick,-{latex[length=0.3cm, bend]}]($(270:0.75)+(-1,0.5)$)
arc (270:315:0.75);
\draw[ultra thick,-{latex[length=0.3cm, bend]}]($(270:1.25)+(-1,0.5)$)
arc (270:315:1.25);
\end{tikzpicture}
\end{document}
