[Tex/LaTex] Drawing a directory listing a la the tree command in TikZ

tikz-treestrees

Good day everyone –

Is there a fast and efficient way to draw directory tree structures (aka depth-indented listings) like the unix's tree command, that is, is there a way to draw the following using TikZ?

root
  |
  |--- dir1
  |     |
  |     |-- a1
  |     |-- a2
  |--- dir2
  |--- dir3

I've checked tikz-tree and tikz-qtree, but the packages always want to grow the tree balanced and not down then to the right.

Any advice is truly appreciated.

Thanks.

Best Answer

I just came across this thanks to the duplicate at Vertical trees with TikZ. The following code seems to work, though I will admit to not testing it fully and making up the numbers so that it just works.

Let's start with some output:

TikZ version of dirtree

Here's the code:

\documentclass[border=10]{standalone}
\usepackage{tikz}

\makeatletter
\newcount\dirtree@lvl
\newcount\dirtree@plvl
\newcount\dirtree@clvl
\def\dirtree@growth{%
  \ifnum\tikznumberofcurrentchild=1\relax
  \global\advance\dirtree@plvl by 1
  \expandafter\xdef\csname dirtree@p@\the\dirtree@plvl\endcsname{\the\dirtree@lvl}
  \fi
  \global\advance\dirtree@lvl by 1\relax
  \dirtree@clvl=\dirtree@lvl
  \advance\dirtree@clvl by -\csname dirtree@p@\the\dirtree@plvl\endcsname
  \pgf@xa=1cm\relax
  \pgf@ya=-1cm\relax
  \pgf@ya=\dirtree@clvl\pgf@ya
  \pgftransformshift{\pgfqpoint{\the\pgf@xa}{\the\pgf@ya}}%
  \ifnum\tikznumberofcurrentchild=\tikznumberofchildren
  \global\advance\dirtree@plvl by -1
  \fi
}

\tikzset{
  dirtree/.style={
    growth function=\dirtree@growth,
    every node/.style={anchor=north},
    every child node/.style={anchor=west},
    edge from parent path={(\tikzparentnode\tikzparentanchor) |- (\tikzchildnode\tikzchildanchor)}
  }
}
\makeatother
\begin{document}
\begin{tikzpicture}[dirtree]
\node {toplevel} 
    child { node {Foo}
            child { node {foo} }
            child { node {bar} }
            child { node {baz} }
    }
    child { node {Bar}
        child { node {foo} }
        child { node {foo} }
        child { node {foo} }
        child { node {foo} }
        child { node {bar} }
        child { node {baz} }
    }
    child { node {Baz}
        child { node {foo} }
        child { node {bar} }
        child { node {baz} }
    };
\end{tikzpicture}
\end{document}

We define a new growth function. The idea is that we have a global counter that keeps track of how many nodes we've processed so far and position the children according to this. The main problem is that the way trees are built: the origin for each branch is the parent node. So we want to apply an absolute transformation (the total height from the root) but have to take into account the relative transformation first. This takes a bit of bookkeeping, but once that's figured out then the rest is ... plain sailing.

The edges are the easy bit - we simply define them to be |-, ie vertical and then horizontal.

Related Solutions

[Tex/LaTex] drawing a syntax tree in tikz

Here you have a starting point:

\documentclass{article} 
\usepackage{tikz}
\usetikzlibrary{trees}

\begin{document}

\begin{tikzpicture}[
  tlabel/.style={pos=0.4,right=-1pt,font=\footnotesize\color{red!70!black}},
]
\node{S}
child {node {a}}
child {node {S} 
  child {node {a}}
  child {node {S}
    child {node {$\varepsilon$}
      edge from parent node[tlabel,pos=0.2] {2}
    }
    edge from parent node[tlabel] {1}
  }
  child {node {B}
    child {node {B}
      child {node {b}
        edge from parent node[tlabel,pos=0.2] {5}
     }
      edge from parent node[tlabel] {4}
    }
    child {node {b}}
  }
    edge from parent node[tlabel] {1}
  }
child {node {B}
  child[missing] {}
  child[missing] {}
  child {node {b}
    edge from parent node[tlabel,pos=0.15,right=2pt] {5}
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};
\end{tikzpicture}

\end{document}

enter image description here

[Tex/LaTex] Draw randomized tree in TikZ

This is an example modified based on page 1 of the forest package documentation.

Note the default anchors of the forest package is not the center of a node, and thus there appear to be white spaces between edges. To fix this, set both parent anchor and child anchor to center, so that they can "connect" with each other. The grow key specifies the direction to which the tree should grow. Since you want it to grow upwards, grow=north would do the trick.

\documentclass[border=2pt]{standalone}

\usepackage{forest}

\begin{document}
\pgfmathsetseed{14285}
\begin{forest}
random tree/.style n args={2}{% #1=max levels, #2=max children
if={#1>0}{repeat={random(0,#2)}{append={[,random tree={#1-1}{#2}]}}}{},
  parent anchor=center, child anchor=center, grow=north},
[,random tree={4}{3}]
\end{forest}
\end{document}

enter image description here

Update: Attaching tree to another node

This is probably not the best way to attach a forest tree to another tikz node, but it's the only thing I can come up with that works.

The idea is to put the forest tree inside a node, and use node positioning commands to "attach" it to another node. The main imperfection is that you have to manually adjust the yshift and \scalebox parameters. (I've tried using inner sep=0pt and outer sep=0pt. But those screwed up the forest picture.)

\documentclass{standalone}
\usepackage{forest}

\begin{document}

\pgfmathsetseed{12987}

\begin{tikzpicture}
  \node(s)[circle,fill=red]{some node};
  \node[yshift=-5.5pt,anchor=south]at(s.north){
    \scalebox{.5}{
      \begin{forest}
        random tree/.style n args={2}{% #1=max levels, #2=max children
        if={#1>0}{repeat={random(0,#2)}{append={[,random tree={#1-1}{#2}]}}}{},
        parent anchor=center, child anchor=center, grow=north},
        [,random tree={3}{3}]
      \end{forest}
    }
  };
\end{tikzpicture}

\end{document}

enter image description here

Best Answer

Related Solutions

[Tex/LaTex] drawing a syntax tree in tikz

[Tex/LaTex] Draw randomized tree in TikZ

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