使 TikZ 决策树的节点在垂直方向上彼此靠近

Question

我目前正在为期刊出版物创建决策树，需要节省空间。

截至目前，我的决策树如下所示

虽然这很好，但我想垂直“压缩”树（即垂直地使节点彼此更靠近）。

有人知道如何使用 TikZ 做到这一点吗？我修改了下面代码中的许多设置……但似乎无法使任何东西正常工作。

\documentclass[letterpaper]{article}
\usepackage{aaai}
\usepackage{tikz} 
\usepackage{pgfplots} 
\usetikzlibrary{shapes,arrows}

\frenchspacing
\setlength{\pdfpagewidth}{8.5in}
\setlength{\pdfpageheight}{11in}

\tikzstyle{block} = [rectangle, draw, fill=white!20, 
    text width=6em, text centered, rounded corners, minimum height=1em]
\tikzstyle{line} = [draw, -latex']
\tikzstyle{cloud} = [draw, text centered, ellipse,fill=gray!15, node distance=0cm, text width=3.3em,
    minimum height=0.0em]
    %begin tree
  \begin{center}
    \begin{tikzpicture}[node distance =0cm, auto]
    % Place nodes
    \small
    \centering
    \node [block] (init) {\scriptsize{history of petty theft?}};
    \node [cloud, left of=init, below of=init, node distance=1.5cm] (end1) {\scriptsize{no violent crime}};
    \node [block, right of=init, below of=init, node distance=1.5cm] (dec1) {\scriptsize{history of weapon use?}};
    \node [cloud, right of=dec1, below of=dec1, node distance=1.5cm] (end2) {\scriptsize{no violent crime}};
    \node [block, left of=dec1, below of=dec1, node distance=1.5cm] (dec2) {\scriptsize{history of employment?}};
    \node [cloud, left of=dec1, below of=dec2, node distance=1.5cm] (end3) {\scriptsize{no violent crime}};
    \node [cloud, right of=dec1, below of=dec2, node distance=1.5cm] (end4) {\scriptsize{violent crime}};
    % Draw edges
    \path [line] (init) -| node [near start, above] {\scriptsize{yes}} (end1);
    \path [line] (init) -| node [near start] {\scriptsize{no}} (dec1);
    \path [line] (dec1) -| node [near start, above] {\scriptsize{yes}} (dec2);
    \path [line] (dec1) -| node [near start] {\scriptsize{no}} (end2);
    \path [line] (dec2) -| node [near start, above] {\scriptsize{yes}} (end3);
    \path [line] (dec2) -| node [near start] {\scriptsize{no}} (end4);
\end{tikzpicture}
\end{center}

Answer 1

为什么不使用树？可以使用 键更改垂直距离level distance。请注意，我已将文本宽度更改为，cm因为字体现在使用 键设置（如果在本例中将或用作键中的单位，则对齐font似乎存在问题；不确定原因）。exemtext width

与往常一样，我在图片前的选项中做了一些额外的工作，因此绘图代码不那么混乱。

\documentclass{standalone}
\usepackage{tikz}
\usetikzlibrary{shapes.geometric}
\begin{document}


\tikzset{
    every node/.style={
        font=\scriptsize
    },
    decision/.style={
        shape=rectangle,
        minimum height=1cm,
        text width=2cm,
        text centered,
        rounded corners=1ex,
        draw,
        label={[yshift=0.125cm]left:yes},
        label={[yshift=0.125cm]right:no},
    },
    outcome/.style={
        shape=ellipse,
        fill=gray!15,
        draw,
        text width=1.5cm,
        text centered
    },
    decision tree/.style={
        edge from parent path={[-latex] (\tikzparentnode) -| (\tikzchildnode)},
        sibling distance=3cm,
        level distance=1.125cm
    }
}


\begin{tikzpicture}

\node [decision] { history of petty theft? }
    [decision tree]
    child { node [outcome] { no violent crime } }
    child { node [decision] { history of weapon use} 
        child { node [decision] { history of employment? } 
            child { node [outcome] { no violent crime } }
            child { node [outcome] { violent crime } }
        }
        child { node [outcome] { no violent crime } }
    };

\end{tikzpicture}

\end{document}