绘制一个特定的层次树形图，其中有从前到后一级的连接器

Question

我使用在这里找到的代码绘制层次树图

\documentclass[tikz,border=10pt]{standalone}
\usepackage[edges]{forest}
\usetikzlibrary{arrows.meta}
\begin{document}
\begin{forest}
  for tree={
    align=center,
    font=\sffamily,
    edge+={thick, -{Stealth[]}},
    l sep'+=10pt,
    fork sep'=10pt,
  },
  forked edges,
  if level=0{
    inner xsep=0pt,
    tikz={\draw [thick] (.children first) -- (.children last);}
  }{},
  [Angiography Based On Medical Imaging Modalities
    [Biplane\\X-Ray/DSA]
    [Magnetic\\Resonance
      [Contrast Enhanced]
      [Non-Contrast Enhanced
        [Time of Flight]
        [Black-Blood]
        [Phase Contrast]
        [T2]
        [T2\textsuperscript{*}]
      ]
    ]
    [Computed-\\Tomography, calign with current]
    [Ultrasound]
    [Fusion of\\Modalities]
  ]
\end{forest}
\end{document}

产生

我应该如何修改代码才能得到如下结果

非常感谢！

编辑

MWE 创建前三个级别：

\documentclass[tikz,french]{beamer}

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[french]{babel}

\usepackage[edges]{forest}
\usetikzlibrary{arrows.meta}
\begin{document}
\begin{forest}
    for tree={
        align=center,
        font=\sffamily,
        edge+={thick, -{Stealth[]}},
        l sep'+=10pt,
        fork sep'=10pt,
    },
    forked edges,
    if level=0{
        inner xsep=0pt,
        tikz={\draw [thick] (.children first) -- (.children last);}
    }{},
    [{\bf Question:} Quels sont les facteurs contribuant à des taux d'échec\\élevés en cours de mécanique de première année?
    [Qu'est-ce\\qui a déjà\\été fait?
    [Revue de\\littérature]
    ]
    [Cours typique\\en mécanique\\de 1e année?
    [``Benchmarking''\\de cours]
    ]
    [Sujets\\probléma-\\tiques?
    [Analyser\\ le travail\\
    des étudiants]
    ]
    [Où le problème\\pourrait-il\\commencer?
    [Analyser\\le dossier\\
    universitaire]
    ]
    ]
\end{forest}
\end{document}

我不知道如何包含从第三级（从上面开始枚举）发出的第四级。

Answer 1

图表的结构非常不同，但如果您想要绘制边界并使所有节点具有相同的高度（在第 1 级），您可能只需添加 draw，其中 level=1{minimum height=8ex,anchor=north}{}，

梅威瑟：

\documentclass[tikz,border=10pt]{standalone}
\usepackage[edges]{forest}
\usetikzlibrary{arrows.meta}
\begin{document}
\begin{forest}
  for tree={draw,
  where level=1{minimum height=8ex,anchor=north}{},
    align=center,
    font=\sffamily,
    edge+={thick, -{Stealth[]}},
    l sep'+=10pt,
    fork sep'=10pt,
  },
  forked edges,
  if level=0{
    inner xsep=0pt,
    tikz={\draw [thick] (.children first) -- (.children last);}
  }{},
  [Angiography Based On Medical Imaging Modalities
    [Biplane\\X-Ray/DSA]
    [Magnetic\\Resonance
      [Contrast Enhanced]
      [Non-Contrast Enhanced
        [Time of Flight]
        [Black-Blood]
        [Phase Contrast]
        [T2]
        [T2\textsuperscript{*}]
      ]
    ]
    [Computed-\\Tomography, calign with current]
    [Ultrasound]
    [Fusion of\\Modalities]
  ]
\end{forest}
\end{document}

Ultrasound或者在节点中添加一个空行

\documentclass[tikz,border=10pt]{standalone}
\usepackage[edges]{forest}
\usetikzlibrary{arrows.meta}
\begin{document}
\begin{forest}
  for tree={draw,
    align=center,
    font=\sffamily,
    edge+={thick, -{Stealth[]}},
    l sep'+=10pt,
    fork sep'=10pt,
  },
  forked edges,
  if level=0{
    inner xsep=0pt,
    tikz={\draw [thick] (.children first) -- (.children last);}
  }{},
  [Angiography Based On Medical Imaging Modalities
    [Biplane\\X-Ray/DSA]
    [Magnetic\\Resonance
      [Contrast Enhanced]
      [Non-Contrast Enhanced
        [Time of Flight]
        [Black-Blood]
        [Phase Contrast]
        [T2]
        [T2\textsuperscript{*}]
      ]
    ]
    [Computed-\\Tomography, calign with current]
    [Ultrasound\\~]
    [Fusion of\\Modalities]
  ]
\end{forest}
\end{document}

至于你对这个问题的补充：

 \documentclass[tikz,french]{beamer}

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[french]{babel}

\usepackage[edges]{forest}
\usetikzlibrary{arrows.meta,positioning}
\begin{document}
\begin{forest}
    for tree={
        align=center,
        font=\sffamily,
        edge+={thick, -{Stealth[]}},
        l sep'+=10pt,
        fork sep'=10pt,
    },
    forked edges,
    if level=0{
        inner xsep=0pt,
        tikz={\draw [thick] (.children first) -- (.children last);}
    }{},
    [{\bf Question:} Quels sont les facteurs contribuant à des taux d'échec\\élevés en cours de mécanique de première année?
    [Qu'est-ce\\qui a déjà\\été fait?
    [Revue de\\littérature,alias=A1]
    ]
    [Cours typique\\en mécanique\\de 1e année?
    [``Benchmarking''\\de cours,alias=A2]
    ]
    [Sujets\\probléma-\\tiques?
    [Analyser\\ le travail\\
    des étudiants,alias=A3]
    ]
    [Où le problème\\pourrait-il\\commencer?
    [Analyser\\le dossier\\
    universitaire,alias=A4]
    ]
    ]
\path (A3.south) -- (A2|-A3.south) coordinate[midway,below=10pt] (aux);
\node[anchor=north,below=15pt of aux] (D) {Dimitris};   
\foreach \X in {1,...,4}
{\draw[thick, -{Stealth[]}] (A\X) |- (aux) -- (D);}
\end{forest}
\end{document}