当圆定义为 `\path node[shape=circle]at(x,y){}` 时，如何指示圆的半径（或大小）？

Question

我需要改变圆圈的大小，但radius这里不起作用。

\documentclass{standalone}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
\path node(ID1)[draw,shape=rectangle]{ID1};
\path node[draw=red,shape=circle]at(ID1.north){};
\end{tikzpicture}
\end{document}

Answer 1

有几个重要的 pgf 键，您可以通过适当设置来控制它们minimum size。inner sep近似inner sep地，if the radius is not "too small". If you want to control the radius very precisely, useinner sep=0pt andminimum size=`。

\documentclass[tikz]{standalone}
\begin{document}
\begin{tikzpicture}
 \path node(ID1)[draw,shape=rectangle]{ID1};
 \path node[draw=red,shape=circle,minimum size=4pt,inner sep=0pt,outer sep=0pt]at(ID1.north){};
 \draw[blue] (ID1.north east) circle[radius=2pt];
\end{tikzpicture}
\end{document}