绘图

Question

有人能告诉我如何制作下图吗beamer：

Answer 1

绘图

使用 TikZ graphdrawing（需要 LuaLaTeX）。

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{graphs,graphdrawing}
\usegdlibrary{trees}
\begin{document}
\begin{tikzpicture}
  \graph[
    tree layout,grow=right,fresh nodes,
    nodes={draw,fill=lightgray,rounded corners}
  ] {
    Patients -> {
      Treatment $A_1$ -> {
        Treatment $B_1$,
        Treatment $B_2$
      },
      Treatment $A_2$ -> {
        Treatment $B_1$,
        Treatment $B_2$
      }
    }
  };
\end{tikzpicture}
\end{document}

森林

或者你也可以使用forest。（感谢@cfr 提供的有关 的提示parent anchor=children,child anchor=parent）

\documentclass{article}
\usepackage{forest}
\begin{document}
\begin{forest}
  for tree={grow=east,parent anchor=children,child anchor=parent,
    draw,fill=lightgray,rounded corners}
  [Patients
    [Treatment $A_1$
      [Treatment $B_1$]
      [Treatment $B_2$]
    ]
    [Treatment $A_2$
      [Treatment $B_1$]
      [Treatment $B_2$] 
    ]
  ]
\end{forest}
\end{document}

tikz-qtree

你也可以滥用tikz-qtree（这实际上是针对语言树的）

\documentclass{article}
\usepackage{tikz-qtree}
\begin{document}
\begin{tikzpicture}[
  grow'=right,level distance=3cm,
  every node/.style={draw,fill=lightgray,rounded corners}
  ]
  \Tree [.Patients
    [.{Treatment $A_1$}
      [.{Treatment $B_1$} ]
      [.{Treatment $B_2$} ]
    ]
    [.{Treatment $A_2$}
      [.{Treatment $B_1$} ]
      [.{Treatment $B_2$} ]
    ]
  ]
\end{tikzpicture}
\end{document}

康特克斯 MkIV

如果您不知道 ConTeXt 是什么，您可以停止阅读。

我用的是charts。

\无页眉和页脚行

\usemodule[chart]

\setupFLOWcharts
  [
    width=9\bodyfontsize,
    height=2\bodyfontsize,
    dx=1\bodyfontsize,
    dy=0pt,
  ]

\starttext

\startFLOWchart[treatment]
  \startFLOWcell
    \shape    {action}
    \name     {pat}
    \location {1,4}
    \text     {Patient}
    \connect  [rl]{tA1}
    \connect  [rl]{tA2}
  \stopFLOWcell

  \startFLOWcell
    \shape    {action}
    \name     {tA1}
    \location {2,2}
    \text     {Treatment $A_1$}
    \connect  [rl]{tA1B1}
    \connect  [rl]{tA1B2}
  \stopFLOWcell

  \startFLOWcell
    \shape    {action}
    \name     {tA1B1}
    \location {3,1}
    \text     {Treatment $B_1$}
  \stopFLOWcell

  \startFLOWcell
    \shape    {action}
    \name     {tA1B2}
    \location {3,3}
    \text     {Treatment $B_2$}
  \stopFLOWcell

  \startFLOWcell
    \shape    {action}
    \name     {tA2}
    \location {2,6}
    \text     {Treatment $A_2$}
    \connect  [rl]{tA2B1}
    \connect  [rl]{tA2B2}
  \stopFLOWcell

  \startFLOWcell
    \shape    {action}
    \name     {tA2B1}
    \location {3,5}
    \text     {Treatment $B_1$}
  \stopFLOWcell

  \startFLOWcell
    \shape    {action}
    \name     {tA2B2}
    \location {3,7}
    \text     {Treatment $B_2$}
  \stopFLOWcell
\stopFLOWchart

\FLOWchart[treatment]

\stoptext

Answer 2

还有一种替代方法，就是用普通的树:-)：

\documentclass{article}
\usepackage{tikz}

\begin{document}
    \begin{tikzpicture}[
      every node/.style = {draw=gray, rounded corners, fill=gray!10, inner sep=2mm},
         level 1/.style = {sibling distance = 22mm},
         level 2/.style = {sibling distance = 11mm},
         level distance = 33mm,
                   grow = right,
edge from parent/.style = {draw, thick, ->},
  edge from parent path = {(\tikzparentnode.east) -- (\tikzchildnode.west)},
                        ]
  \node  {Patients}
    child { node {Treatment $A_1$}
        child { node {Treatment $B_1$}}
        child { node {Treatment $B_2$}}
          }
    child { node {Treatment $A_2$}
        child { node {Treatment $B_1$}}
        child { node {Treatment $B_2$}}
          };
    \end{tikzpicture}
\end{document}

Answer 3

更接近OP图：

来源：

\documentclass{article}
\usepackage{tikz}
\usepackage{tikz-qtree}

\begin{document}
  \begin{tikzpicture}[grow' = right,
                 line width = 1.5pt,
             level distance = 44mm,
          every node/.style = {shape = rectangle,
                               minimum size = 13mm,
                               text width = 24mm,
                               rounded corners = 2mm,
                               draw,
                               fill=black!10,
                               align=center,
                              },
             level 1/.style = {sibling distance = 36mm},
             level 2/.style = {sibling distance = 17mm},
                              ]
      \node {Patients}
      child {node {Treatment $ A_1 $}
        child {node {Treatment $ B_2 $}}
        child {node {Treatment $ B_1 $}}}
      child {node {Treatment $ A_2 $}
        child {node {Treatment $ B_1 $}}
        child {node {Treatment $ B_2 $}}};
  \end{tikzpicture}
\end{document}