# Multicols not breaking procedures in algorithm2e

I'm having a problem with the package multicol. I'm trying to split an algorithm into two columns. In particular, this algorithm is made up by two procedures. Unfortunately, in this particular case, one procedure is definitely longer than the other.

I'd like to know if there is a way to force multicol to split this algorithm evenly, and better if I can chose whether to split evenly or split by function on a case-by-case basis.

I've tried using \columnbreak in the middle but it did not work.

\documentclass[10pt,twoside]{report}

\usepackage[utf8]{inputenc}

\usepackage[a4paper,width=150mm,top=25mm,bottom=25mm,bindingoffset=6mm]{geometry}

\usepackage{fancyhdr}
\pagestyle{fancy}

\usepackage[numbers]{natbib}
\usepackage{color}

\usepackage{amsmath}
\usepackage{amsfonts}

\usepackage[ruled]{algorithm2e}
\usepackage{multicol}

\begin{document}

\begin{algorithm}
\caption{My lovely procedure}
\begin{multicols}{2}
\SetKwFunction{funone}{MyFunction}
\SetKwFunction{funtwo}{OtherFun}

\SetKwProg{main}{Algorithm}{}{}
\main{\funone{b}}{
\KwData{MyData b}
\nl     \While{this is true}{
\nl         Do X\;
\nl         Do X\;
}
\nl     Do X\;
}

\setcounter{AlgoLine}{0}
\SetKwProg{foo}{Procedure}{}{}
\foo{\funtwo{h, s, d}}{
\KwData{MyData h, s, d}
\nl     Do X\;
\nl     Do X\;
\nl     \If{Is his true?}{
\nl         \eIf{Is this true?}{
\nl             Do X\;
}{
\nl             Do X\;
\nl             Do X\;
\nl             Do X\;
}
}
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
}
\end{multicols}
\end{algorithm}

\end{document}

• Algorithm is a float, isn't it? Try using minipages instead. – John Kormylo Oct 6 '14 at 2:55
• Never mind. That didn't work either. – John Kormylo Oct 6 '14 at 2:58
• After much experimentation, I have concluded that the output of algorithm must entirely fit in one column. It will not break, period. – John Kormylo Oct 6 '14 at 4:12
• – jub0bs Oct 6 '14 at 6:54

If you really want to break it evenly, you can put it into a single column and use \clipbox from the adjustbox package to literally cut it in half.

\documentclass[10pt,twoside]{report}

\usepackage[utf8]{inputenc}

\usepackage[a4paper,width=150mm,top=25mm,bottom=25mm,bindingoffset=6mm]{geometry}

\usepackage{fancyhdr}
\pagestyle{fancy}

\usepackage[numbers]{natbib}
\usepackage{color}

\usepackage{amsmath}
\usepackage{amsfonts}

\usepackage[ruled]{algorithm2e}

\newsavebox{\tempbox}

\begin{document}

\savebox{\tempbox}{% create image
\begin{minipage}[c]{0.45\textwidth}%
\begin{algorithm*}[H]
\SetKwFunction{funone}{MyFunction}
\SetKwFunction{funtwo}{OtherFun}

\SetKwProg{main}{Algorithm}{}{}
\main{\funone{b}}{
\KwData{MyData b}
\nl     \While{this is true}{
\nl         Do X\;
\nl         Do X\;
}
\nl     Do X\;
}
\setcounter{AlgoLine}{0}
\SetKwProg{foo}{Procedure}{}{}
\foo{\funtwo{h, s, d}}{
\KwData{MyData h, s, d}
\nl     Do X\;
\nl     Do X\;
\nl     \If{Is his true?}{
\nl         \eIf{Is this true?}{
\nl             Do X\;
}{
\nl             Do X\;
\nl             Do X\;
\nl             Do X\;
}
}
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
\nl     Do X\;
}
\end{algorithm*}%
\end{minipage}}

\begin{algorithm}
\caption{My lovely procedure}
\clipbox{0pt {\depth} 0pt {\baselineskip}}{\usebox{\tempbox}}\hfill
\raisebox{\depth}{\clipbox{0pt 1ex 0pt {\height}}{\usebox{\tempbox}}}
\end{algorithm}

\end{document}

• It does look somewhat weird though. Do you think otherwise I could do something like create a procedure with no title, split the code between the two and try to sneak it in like that? – Svalorzen Oct 6 '14 at 14:59
• Yes, it would probably be better to put the title and the caption outside the \savebox. I'm not sure if hyperref would even be able to locate it otherwise. This would mean two separate expansions of algorithm. – John Kormylo Oct 6 '14 at 19:22
• Okay, I modified the solution to separate the caption from the \savebox. – John Kormylo Oct 6 '14 at 19:41