3

This is fine:

\documentclass{article}
\usepackage[boxed]{algorithm2e}

\begin{document}

\begin{algorithm}
    $x \gets x$\;
    \caption{Identity}
\end{algorithm}

\end{document}

But this, which uses the predefined environment "function" (p. 4 of the manual)

\documentclass{article}
\usepackage[boxed]{algorithm2e}

\begin{document}

\begin{function}
    $x \gets x$\;
    \caption{Identity}
\end{function}

\end{document}

produces this error

Runaway argument?
Identity@\endcsname ##1{\FuncSty {\algocf@captname Identity@(}\ArgSty \ETC.
./sandbox.tex:10: Paragraph ended before \algocf@captname was complete.
<to be read again> 
                   \par 
l.10 

? r
OK, entering \nonstopmode...
./sandbox.tex:10: Missing \endcsname inserted.
<to be read again> 
                   \par 
l.10 

)
! Emergency stop.

I use TexShop which (I believe) compiles with

simpdftex latex --maxpfb --extratexopts "-file-line-error -synctex=1"

Any help would be appreciate, I am out of ideas.

vrbatim
  • 731
  • 6
  • 13

1 Answers1

5

This is explained in page 17 of the documentation (talking about the procedure environment, but the same remark applies to function):

the syntax of the \caption command is restricted as follow: you MUST put a name followed by 2 braces like this Name(). You can put arguments inside the braces and text after. If no argument is given, the braces will be removed in the title.

A complete example:

\documentclass{article}
\usepackage[boxed]{algorithm2e}

\begin{document}

\begin{function}
    $x \gets x$\;
    \caption{Identity()}
\end{function}

\end{document}

enter image description here

Gonzalo Medina
  • 505,128
  • Thanks, I totally missed that in the manual.

    However, my precise problem is that my algorithm makes recursive calls and I need to make this clear in the algorithm environment. In the very least I want to move the caption to the top but

    \usepackage[boxed]{algorithm2e}

    produces (bizarrely)

    LaTeX Error: Unknown option `boxedruled' for package `algorithm2e'.

    despite it also being a valid option from the manual.

     – vrbatim Jul 27 '13 at 16:28