5

Here's a picture example of what I want:

enter image description here

I'm able to make the type of arc that I want with this command:

\draw (-2,-2) [black,thick,dashed,domain=45:180] plot ({cos(\x)}, {sin(\x)}) ;

But it always creates the arc at the very top of the tree, even when I put the command inside the tree in the node where I want the arc. Here's the code I'm using:

begin{forest}
[TP [T\textsuperscript{0}]
[vP [DP\textsubscript{???},circle,draw]
[v' [v\textsuperscript{0}]
[VP,tikz={\draw[black,thick,dashed,domain=45:180] (2,2) plot ({cos(\x)}, {sin(\x)}) ;}
[V\textsuperscript{0}] [DP\textsubscript{???},circle,draw]
]]]]
\end{forest}
user47581
  • 53
  • 1
    Can you please post a minimla document with the code you are currently using for the tree? – Gonzalo Medina Mar 08 '14 at 17:29
  • Welcome to TeX.SX. Questions about how to draw specific graphics that just post an image of the desired result are really not reasonable questions to ask on the site. Please post a minimal compilable document showing that you've tried to produce the image and then people will be happy to help you with any specific problems you may have. See minimal working example (MWE) for what needs to go into such a document. A suggestion: Do us a favour and change your username to something more telling than "user1234". – Martin Schröder Mar 08 '14 at 17:30
  • My mistake, this is my first time on this site and I didn't even think to read the posting guidelines. I've added my code to the original post. – user47581 Mar 08 '14 at 17:40

1 Answers1

5

You can use the name= key to name some reference node(s) and then use an arc path to draw the arc:

\documentclass{article}
\usepackage{forest}
\usepackage{fixltx2e}
\begin{document}

\begin{forest}
[TP 
  [T\textsuperscript{0}]
  [vP 
    [DP\textsubscript{???},circle,draw]
    [v' 
      [v\textsuperscript{0}]
      [VP
        [V\textsuperscript{0},name=left] 
        [DP\textsubscript{???},circle,draw]
      ]
    ]
  ]
]
\draw[double] 
  ([xshift=-12pt]left) arc[start angle=180,end angle=60,radius=2cm];
\end{forest}

\end{document}

enter image description here

Gonzalo Medina
  • 505,128
  • That's perfect, thank you! I apologize for not including the code that I was working with. I'll be sure to not forget that when I post any other questions in the future. – user47581 Mar 08 '14 at 17:50