# Ratio of the expression and the corresponding description fix in Beamer

I want to modify the display of my equation little bit. Below is the code which I used to show the ratio of two expressions and use a pointer for the descrption of the items.

I was able to show the expressions but I was wondering if it is possible to use them as a real fraction just like the expression we get while using \frac function.

\tikzstyle{na} = [baseline=-.5ex]

\begin{equation*}
a_i(t,x) =
\tikz[baseline]{
\node[fill=blue!20,anchor=base] (t1)
{$\tau C_i(t,x,\tau )\partial \tau$};
} /
\tikz[baseline]{
\node[fill=red!20, ellipse,anchor=base] (t2)
{$C_i(t,x,\tau) \partial \tau$};
}
\end{equation*}

\item Coriolis acceleration
\tikz[na] \node[coordinate] (n1) {};
\item Transversal acceleration
\tikz[na]\node [coordinate] (n2) {};
\end{itemize}

% Now it's time to draw some edges between the global nodes. Note that we
% have to apply the 'overlay' style.
\begin{tikzpicture}[overlay]
\path[->]<1-> (n1) edge [bend right] (t1);
\path[->]<2-> (n2) edge [bend right] (t2);

\end{tikzpicture}


The output of the above code is as follows:

• Please add a minimal working example (MWE), complete with \documentclass{...}, the required \usepackage{...}'s, \begin{document}, \end{document}. The code should be compilable without requiring modification. – jub0bs Mar 20 '13 at 8:19
• This is possible (I just did it.) but I had to add some TikZ library and a package that wasn't mentioned in your "MWE". The result looked dreadful because the shapes overlapped. I think you should stick to a presentation with a reduced wow-this-is-amazing factor. – user10274 Mar 20 '13 at 8:38

Here's a working example:

\documentclass{beamer}
\usepackage{tikz}
\usetikzlibrary{shapes}
\tikzstyle{na} = [baseline=-.5ex]
\tikzstyle{every picture}=[remember picture]

\begin{document}
\begin{frame}
\begin{equation*}
a_i(t,x) =
\frac{
\tikz[baseline]{
\node[fill=blue!20,anchor=base] (t1)
{$\tau C_i(t,x,\tau )\partial \tau$};
}}{
\tikz[baseline]{
\node[fill=red!20, ellipse,anchor=base] (t2)
{$C_i(t,x,\tau) \partial \tau$};
}}
\end{equation*}

\item Coriolis acceleration
\tikz[na] \node[coordinate] (n1) {};
\item Transversal acceleration
\tikz[na]\node [coordinate] (n2) {};
\end{itemize}

% Now it's time to draw some edges between the global nodes. Note that we
% have to apply the 'overlay' style.
\begin{tikzpicture}[overlay]
\path[->]<1-> (n1) edge [bend left] (t1);
\path[->]<2-> (n2) edge [bend right] (t2);

\end{tikzpicture}
\end{frame}
\end{document}


• @ Matthew: Thank you so much for your answer. Actually I had tried using this way, may be the syntax was wrong. Thanks. – Jdbaba Mar 20 '13 at 17:59
• Your upvote and check are thanks enough. :-) – Matthew Leingang Mar 20 '13 at 20:07