我该如何绘制这样的决策树？

Question

我尝试过普通的 TikZ 和 Forest，但无法接近。谢谢！

Answer 1

这应该可以帮助您开始使用forest。edges必须加载该库才能使用forked edge。

\documentclass{article}

\usepackage{forest}
\useforestlibrary{edges}

\begin{document}

\begin{forest}
for tree={forked edge,
l sep=.5cm,
s sep=.5cm,
if n children=0{tier=leaf}{}
}
[$X_2<1$
    [$X_1<1$
        [$-1.80$]
        [0.63]
    ]
    [$X_2<2$
        [$X_1<0$
            [$-1.06$]
            [0.21]
        ]
        [2.49]
    ]
]
\end{forest}

\end{document}

Answer 2

将 Mathcha 编辑器与 TikZ 结合使用。

\documentclass[a4paper,12pt]{article}
\usepackage{tikz}


\begin{document}
\tikzset{every picture/.style={line width=0.75pt}} %set default line width to 0.75pt        

\begin{tikzpicture}[x=0.75pt,y=0.75pt,yscale=-1,xscale=1]
%uncomment if require: \path (0,300); %set diagram left start at 0, and has height of 300

%Shape: Right Angle [id:dp48723979825727537] 
\draw   (271,108) -- (341,108) -- (341,178) ;
%Shape: Right Angle [id:dp539305270770597] 
\draw   (271,108) -- (201.8,108) -- (201.8,178) ;

%Shape: Right Angle [id:dp566680910502753] 
\draw   (198.11,178.27) -- (248,178.27) -- (248,220.46) ;
%Shape: Right Angle [id:dp7717469994484694] 
\draw   (198.11,178.27) -- (148.8,178.27) -- (148.8,220.46) ;

%Shape: Right Angle [id:dp8653500039706887] 
\draw   (339.56,177.27) -- (380.8,177.27) -- (380.8,197.8) ;
%Shape: Right Angle [id:dp8151753688592149] 
\draw   (339.56,177.27) -- (298.8,177.27) -- (298.8,197.8) ;

%Shape: Right Angle [id:dp13534020188934037] 
\draw   (302.75,198.27) -- (328.8,198.27) -- (328.8,219.8) ;
%Shape: Right Angle [id:dp4875428770343304] 
\draw   (302.75,198.27) -- (277,198.27) -- (277,219.8) ;

%Straight Lines [id:da01652899110190509] 
\draw    (271,99) -- (271,110) ;

% Text Node
\draw (246,78.86) node [anchor=north west][inner sep=0.75pt]    {$X2< 1$};
% Text Node
\draw (176,157.86) node [anchor=north west][inner sep=0.75pt]    {$X1< 1$};
% Text Node
\draw (316,158.86) node [anchor=north west][inner sep=0.75pt]    {$X2< 2$};
% Text Node
\draw (273,181.4) node [anchor=north west][inner sep=0.75pt]    {$X1< 0$};
% Text Node
\draw (124.8,221.4) node [anchor=north west][inner sep=0.75pt]  [font=\small]  {$-1.80$};
% Text Node
\draw (225.8,221.86) node [anchor=north west][inner sep=0.75pt]  [font=\small]  {$0.63$};
% Text Node
\draw (262.8,222.2) node [anchor=north west][inner sep=0.75pt]  [font=\small]  {$-1.06$};
% Text Node
\draw (312.8,223.2) node [anchor=north west][inner sep=0.75pt]  [font=\small]  {$0.21$};
% Text Node
\draw (364.8,201.2) node [anchor=north west][inner sep=0.75pt]  [font=\small]  {$2.49$};


\end{tikzpicture}

\end{document}