dot2tex and math mode

Question

I have successfully installed dot2texi but I'm facing an issue with the math mode. The sign (_) in math mode works fine however other symbols do not work. For example it ignores the bar over b in the following example.

\documentclass{article}

\usepackage{dot2texi}
\usepackage{tikz}
\usetikzlibrary{shapes,arrows}
\makeatletter
\@ifundefined{verbatim@out}{\newwrite\verbatim@out}{}
\makeatother
\begin{document}
\begin{dot2tex}[tikz,options=-t math]
digraph G {
a\bar{b} -> c;
}
\end{dot2tex}

\end{document}

is there anyway to fix this? Also, is it possible to write regular LaTeX and $$ in the dot2texi without worring about define it as math/verbatim/raw mode.

Answer 1

You are not using correct dot language.

Underscores in node names work fine indeed, as node names have to consist of digits, letters, and underscores, not starting with a digit. Your graph defines nodes a, bar, b, and c, where b is contained in a subgraph.

What you actually want to achieve is probably:

\documentclass{article}

\usepackage{dot2texi}
\usepackage{tikz}
\usetikzlibrary{shapes,arrows}
\makeatletter
\@ifundefined{verbatim@out}{\newwrite\verbatim@out}{}
\makeatother

\begin{document}
\begin{dot2tex}[tikz,options=-t math]
digraph G {
n0[label="a\bar{b}"];
n0 -> c;
}
\end{dot2tex}
\end{document}

which yields

Regarding your second question, you can put LaTeX commands, including math stuff ($...$) in any label if you add them as texlbl attributes, see the dot2tex manual for details. But remember that the graph must still be defined in valid dot language.