TikZ：如何绘制一个以中心点为圆的节点？

Question

对于我试图构建树的图表，节点是圆圈。我需要一些节点用中心点标记（类似于textbullet节点中心）。我想复制的图像是：

到目前为止我的树是：

\documentclass{article}

\usepackage{tikz}

\begin{document}
\begin{figure}
  \centering
  \begin{tikzpicture}[sibling distance = 2cm,
                  level 2/.style = {sibling distance = 1cm}]
    \node[circle,draw]{}
      child{ node[circle, draw]{}
        child{ node[circle, draw]{}
        child{ node[circle, draw]{}}
        child{ node[circle, draw]{}}
      }
      child{ node[circle, draw]{}}
      child{ node[circle, draw]{}}
    }
    child{ node[circle, draw]{}
      child{ node[circle, draw]{}
        child{ node[circle, draw]{}}
        child{ node[circle, draw]{}}
      }
    };
 \end{tikzpicture}
 \caption{A tree}
 \label{fig:tree}
 \end{figure}
\end{document}

Answer 1

众多选项中，有三个。

\documentclass[tikz,border=3mm]{standalone}
\begin{document}
\begin{tikzpicture}[cc1/.style={circle,draw,node contents={\textbullet}},
cc2/.style={circle,draw,inner sep=0pt,minimum size=1cm,path picture={
\fill (0,0) circle[radius=2mm];},node contents={}}]
\path (0,0) node[circle,draw]{\textbullet} 
 (1,0) node[cc1] (2,0) node[cc2];
\end{tikzpicture}
\end{document}

Answer 2

新答案

child您可以通过简单地编写而不是child{ node[circle, draw]{}}创建适用于所有子项的样式来简化代码 ：

every child node/.style={circle,draw,node contents=\textbullet}

\documentclass{article}

\usepackage{tikz}

\begin{document}
\begin{figure}
  \centering
  \begin{tikzpicture}[sibling distance = 2cm,
                  level 2/.style = {sibling distance = 1cm},
                  every child node/.style={circle,draw,anchor=center,node contents=\textbullet}]
    \node[circle,draw]{\textbullet}
      child{ 
        child{ 
        child
        child
      }
      child
      child
    }
    child{ 
      child{ 
        child
        child
      }
    };
 \end{tikzpicture}
 \caption{A tree}
 \label{fig:tree}
 \end{figure}
\end{document}

旧答案

像这样 ？

\documentclass[border=5mm,tikz]{standalone}
\begin{document}

\begin{tikzpicture}
\node[anchor=center,draw,circle] at (0,0) {\textbullet};
\end{tikzpicture}
\end{document}