# Beamer and pseudocode

I am preparing a presentation with beamer from a previous paper written in latex. I want to insert in a slide the pseudocode

    \begin{algorithm}
\begin{algorithmic}[1]
\FOR{$i=1$ to $N$}
\FOR{$j=1$ to $JJJJ} \STATE$energy[i*JJJ+j] =$\\$ interpolate(AAA[i*JJJ+j], ZZZ)$\ENDFOR \ENDFOR \end{algorithmic} \caption{pseudocode for the calculation of } \label{alg:seq} \end{algorithm}  but I get problems since the beamer document does not compile. I tried to use the same packages that in the latex document. I also tried to find examples through google but nothing. Could you tell me what is wron here or how could I add pseudocode in beamer )examples on the net, etc)? • Could you include your preamble? Also, when you say it "does not compile", what error do you get? – Loop Space Aug 25 '11 at 18:28 • There's a missing closing $ in your code in the line \FOR{$j=1$ to $JJJJ}; it should be \FOR{$j=1$to$JJJJ$}. – Gonzalo Medina Aug 25 '11 at 18:55 ## 3 Answers The floating object algorithm doesn't behave well with beamer (which onviously disables floating objects). To prevent problems you can 1) use the H placement specifier for algorithm, or 2) drop the algorithm environment and use the \captionof command from the caption package if a caption is needed. The following example shows the first approach: \documentclass[12pt]{beamer} \usepackage{algorithm,algorithmic} \begin{document} \begin{frame} \begin{algorithm}[H] \begin{algorithmic}[1] \FOR{$i=1$to$N$} \FOR{$j=1$to$JJJJ$} \STATE$energy[i*JJJ+j] = interpolate(AAA[i*JJJ+j], ZZZ)$\ENDFOR \ENDFOR \end{algorithmic} \caption{pseudocode for the calculation of } \label{alg:seq} \end{algorithm} \end{frame} \end{document}  • ok, it did the trick! gracias gonzalo – Open the way Aug 26 '11 at 8:48 • how can one regulate algorithm's font size? – Open the way Aug 26 '11 at 8:49 • @flow: your last request does not directly depend on the original question, so it would be better to open a fresh new question. – Gonzalo Medina Aug 26 '11 at 17:17 • The preamble \usepackage{algorithm,algorithmic} does not work for me. I changed it to usepackage{algpseudocode} and this works. Don't know why. – hengxin Nov 26 '13 at 7:55 • Load the required packages (for example algorithmic and algorithm2e or algorithm) • Use the float package with H option for the floating algorithm environment option to get a fixed position • Use the fragile option for the frame if you get strange errors, it can fix problems with verbatim text and listings Compilable example: \documentclass{beamer} \usetheme{Singapore} \usepackage{algorithm2e} \usepackage{algorithmic} \usepackage{float} \begin{document} \section{Test} \begin{frame}[fragile] \begin{algorithm}[H] \begin{algorithmic}[1] \FOR{$i=1$to$N$} \FOR{$j=1$to$JJJJ$} \STATE$energy[i*JJJ+j] =$\\$ interpolate(AAA[i*JJJ+j], ZZZ)\$
\ENDFOR
\ENDFOR
\end{algorithmic}
\caption{pseudocode for the calculation of }
\label{alg:seq}
\end{algorithm}
\end{frame}
\end{document}


• You can use the H specifier in beamer without explicitly loading the float package (see my answer). – Gonzalo Medina Aug 25 '11 at 19:21

We add a new slide to Beamer documentation, using this \begin{frame}...\end{frame} and algorithm using \begin{algorithm}...\end{algorithm} If you try to directly embed algorithm in the frame it would not work.

Therefore use \scalebox{}{...}

Syntax:

\begin{frame}
\scalebox{1}{\begin{algorithm}...\end{algorithm}}
\end{frame}


https://beerensahu.wordpress.com/2014/11/17/documentation-how-to-write-algorithms-in-latex-beamer-slids/