How do I add a caption to a diagram generated with qtree?

Question

I have a diagram that I created with qtree, but would like to add a caption to it. How can this be done?

Answer 1

One option would be to use the newfloat package to define a new floating object, so then you can use the standard \caption command:

\documentclass{article}
\usepackage{qtree}
\usepackage{newfloat}

\DeclareFloatingEnvironment[fileext=lod]{diagram}

\begin{document}

\begin{diagram}
\centering
\Tree [.S This [.VP [.V is ] \qroof{a simple tree}.NP ] ]\par
\caption{the caption for this diagram}
\end{diagram}

\end{document}

The package offers some other customization possibilities and it cooperates with the caption package.