Own equation environment for - R syntax formulas

Question

I'd like to be able to write down formulas in R syntax as equations, i.e. I'd like to do something like this:

\begin{requation}
time ~ (poly(I(1/nprocs), 2) + poly(ndoms, 2) + poly(nDOF, 2))^3
\end{requation} 

while the equation would be numbered together with ordinary equations and its content would be the simple text with \texttt{}. So, I need no math-mode inside the environment.

Do you know, how to do it?

---

EDIT

I've tried something like this

\newenvironment{requation}
{%
\VerbatimEnvironment
\begin{Verbatim}
}
{
\end{Verbatim}
\refstepcounter{equation}\hfill(\theequation)}

The only problem is, that in this case there is a newline after \end{Verbatim} which I don't want - is there any possibility to get rid of it?

Answer 1

Here's a simple way to get what you want without defining a new environment, or using any extra packages:

\documentclass{article}
\begin{document}
\begin{equation}
\verb"time ~ (poly(I(1/nprocs), 2) + poly(ndoms, 2) + poly(nDOF, 2))^3"
\end{equation} 
\end{document}

Notice that the equation number has been pushed to the line below; that's because the R code you gave as an example is rather long, and the default text width is not that wide.

You could avoid typing the \verb bit if you use the shortvrb package.

\documentclass{article}
\usepackage{shortvrb}\MakeShortVerb{"}
\begin{document}
\begin{equation}
"time ~ (poly(I(1/nprocs), 2) + poly(ndoms, 2) + poly(nDOF, 2))^3"
\end{equation} 
\end{document}

but that would have an effect on the rest of your document, and you might struggle to find a short verb character that is not part of R syntax. The advantage of the first solution is that you can change the character each time, as required:

\documentclass{article}
\begin{document}
\begin{equation}
\verb|time ~ (poly(I(1/nprocs), 2) + poly(ndoms, 2) + poly(nDOF, 2))^3|
\end{equation} 
\end{document}

In all cases, the verbatim bit must be all on one line.