如何使用 tikz 标记树形图上的节点

Question

我有一棵分支树，目前只显示节点。我想给它添加更多标签，但我不知道该怎么做。我附上了目前的代码，以及一张我想要的图片。我该怎么做？

\begin{figure}[h]
\begin{center}
\begin{tikzpicture}
    \tikzstyle{every node}=[circle,inner sep=1.5pt,draw,fill]
\draw node {} child {node {}
    child {
        node {}
        child { node {} child { node {} }child {node {}} child {node {}  }}
    }
    child { node {} }}

;
\end{tikzpicture}
\caption{ Branched tree}
\end{center}
\end{figure}

Answer 1

\documentclass[border=2mm]{standalone}
\usepackage{tikz}
\usetikzlibrary{positioning}
\begin{document}
\begin{tikzpicture}%
   [tn/.style={circle,inner sep=1.5pt,draw,fill}% tree node
   ]
   \draw 
     node[tn] (1) {}
       child { node[tn] (11) {}
         child { node[tn] (111) {}
           child { node[tn] (1111) {}
             child { node[tn] (11111) {} }
             child { node[tn] (11112) {} }
             child { node[tn] (11113) {} }
           }
         }
         child { node[tn] (112) {}}
       };
    \node[left =of 11111] (t4) {$t=4$};
    \node      at (1    -| t4) {$t=0$};
    \node      at (11   -| t4) {$t=1$};
    \node      at (111  -| t4) {$t=2$};
    \node      at (1111 -| t4) {$t=3$};
    \node[right=of 11113] (R4) {$R_4=3$};
    \node      at (1    -| R4) {$R_0=1$};
    \node      at (11   -| R4) {$R_1=1$};
    \node      at (111  -| R4) {$R_2=2$};
    \node      at (1111 -| R4) {$R_3=1$};
\end{tikzpicture}
\end{document}

Answer 2

如果有人必须绘制许多这样的树，这里有一个森林风格，nodes alone，它会自动格式化和标记树。显然，标签中的内容细节可以根据需要进行定制。我假设 MWE 中的数字代表级别数（t=0, t=1, ...和R_0=??, R_1=??, ...）以及该级别的节点数（1, 1, 2, 1, 3）。根据需要进行修改。

我添加了第二个更大的例子只是为了说明其潜力：一旦定义了样式，树木本身就可以非常简洁地指定。

例如，原始树可以用

\begin{forest}
  nodes alone
  [, baseline
    [
      [
        [
          [][][]
        ]
      ]
      []
    ]
  ]
\end{forest}

以及更大的演示树

\begin{forest}
  nodes alone
  [, baseline
    [
      [
        [
          [][][]
        ]
      ]
      [[[[[[[[][[[[[]]][]]][[][]]][][][[]]]]][[[][]]]][[]]][[][[][]]]]
    ]
    [
      [[[]][][[[]]]]
    ]
  ]
\end{forest}

完整代码：

\documentclass[border=10pt]{standalone}
\usepackage{forest}
\forestset{
  nodes alone/.style={
    for tree={
      parent anchor=center,
      child anchor=center,
      anchor=center,
      inner sep=1.5pt,
      circle,
      fill,
      s sep'+=10pt,
    },
    before typesetting nodes={
      tempcounta/.max={>O{level}}{r,tree},
      for nodewalk={
        root,
        tikz+={
          \coordinate (w) at (current bounding box.west);
          \coordinate (e) at (current bounding box.east);
        },
        until={>OR={level}{tempcounta}}{next node},
        Nodewalk={}{current and ancestors}{
          tempcountc/.option=level,
          tempcountd'=0,
          Nodewalk={}{filter={fake=root,tree}{>OR={level}{tempcountc}}}{tempcountd'+=1},
          tikz+/.process={
            ORw2{level}{tempcountd}{
              \node [anchor=east, xshift=-10mm] at (w |- .center) {$t=##1$};
              \node [anchor=west, xshift=10mm] at (e |- .center) {$R_{##1}=##2$};
            }
          },
        }
      }{},
    },
  },
}
\begin{document}
\begin{forest}
  nodes alone
  [, baseline
    [
      [
        [
          [][][]
        ]
      ]
      []
    ]
  ]
\end{forest}
\begin{forest}
  nodes alone
  [, baseline
    [
      [
        [
          [][][]
        ]
      ]
      [[[[[[[[][[[[[]]][]]][[][]]][][][[]]]]][[[][]]]][[]]][[][[][]]]]
    ]
    [
      [[[]][][[[]]]]
    ]
  ]
\end{forest}
\end{document}