答案1
例如,这里有一个获取上图的简短代码:
\documentclass[border=3pt, x11names]{standalone}
\usepackage{amsmath}
\DeclareMathOperator{\re}{Re}
\DeclareMathOperator{\im}{Im}
\usepackage{pst-plot, pst-arrow}
\begin{document}
\psset{dimen=middle, arrowinset=0.12, unit=3cm, linejoin=1, dash=3pt 2pt}
\begin{pspicture}(-1.4,-1.4)(1.6,1.4)
\psaxes[linecolor=LightSteelBlue3,xAxis=true,yAxis=true,labels=none,ticks=none]{->}(0,0)(-1.3,-1.32)(1.3,1.3)[$ \re z $,0][$\im z$,0]
\psset{linecolor =SteelBlue4, linewidth = 1.2pt, ArrowInsidePos=0.3}
\psline[ArrowInside=->](1;355)(0.2;334)\psline[ArrowInside=->](0.2;26)(1;5)
\pscustom{\psarc{->}{1}{5}{60}\psarc(0,0){1}{60}{355}\psline(1;355)(0.2;334)%
\psarcn{->}{0.2}{334}{135}\psarcn(0,0){0.2}{135}{26}\psline(0.2;26)(1;5)%
\closepath}
\psdot[dotstyle=x](-0.4,0)\uput[d](-0.4,0){$z = -1_{\varepsilon} $}
\psline[linewidth=0.4pt, linestyle=dashed]{<->}(1;110)(0,0)(0.2;-130)
\uput{2pt}[ur](1;55){$C_R$}\uput{1pt}[ul](0.2;135){$C_\varepsilon$}
\uput{2pt}[ur](0.7;110){$R$}\uput{2pt}[ul](0.5,0.1){$I^{+} $}\uput{2pt}[d](0.75,-0.1){$I^{-} $}
\end{pspicture}
\end{document}