[Tex/LaTex] way to reference the line number in algorithm 2e

algorithm2e

Say I have algorithm appear as followed

enter image description here

Is it possible to reference the line number using ~\ref or any other possiblities?

Best Answer

Yes, it's possible. :)Use the normal \label command in the line you want to refer (page 4 of the algorithm2e manual), then use \ref to display the line number.

\documentclass{article}

\usepackage[linesnumbered]{algorithm2e}

\begin{document}

Line \ref{alg:goto} is important.

\vspace{2em}

\begin{algorithm}[H]
\KwData{this text}
\KwResult{how to write algorithm with \LaTeX2e }
initialization\;
\While{not at end of this document}{
read current\;
\eIf{understand}{
go to next section\;\label{alg:goto}
current section becomes this one\;
}{
go back to the beginning of current section\;
}
}
\end{algorithm}

\end{document}

The output:

Line 5

Related Solutions

[Tex/LaTex] Restyling the caption in an algorithm created with algorithm2e

The algorithm2e package offers \SetAlgoCaptionSeparator to change the caption separator and \AlCapFnt to control the font for the label of the caption:

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

\SetAlgoCaptionSeparator{.}
\renewcommand\AlCapFnt{\normalfont\scshape}

\begin{document}

\begin{algorithm}[H]
\caption{Caption.}
pseudocode
\end{algorithm}

\end{document}

enter image description here

[Tex/LaTex] Algorithm with chapter number

Since you are using both the algorithm2e and algorithm packages, and both of them implement some same commands/environments, you had to use the algo2e option for algorithm2e to prevent a clash and this overrides the settings for the counter that you set as options for algorith2e, since the environment that will be used is the one from algorithm. You have three possible solutions:

If you don't need the algorithm package, load only algorithm2e and not algorithm and load the former without the algo2e option:

\documentclass[11pt]{book}
\usepackage[ruled,vlined,linesnumbered,resetcount,algochapter]{algorithm2e}

\begin{document}

\chapter{chapter1}
\begin{algorithm}[H]
\centering
test
\caption{algo}
\label{algo1}
\end{algorithm}

\end{document}

enter image description here

If you really need both algorithm2e and algorithm in your document, and you want to use the algorithm environment (from the algorithm package) add the following lines to your preamble, after loading the packages:

\makeatletter 
\renewcommand\thealgorithm{\thechapter.\arabic{algorithm}} 
\@addtoreset{algorithm}{chapter} 
\makeatother

A complete example:

\documentclass[11pt]{book}
\usepackage[ruled,vlined,linesnumbered,algo2e,resetcount,algochapter]{algorithm2e}
\usepackage{algorithm}

\makeatletter 
\renewcommand\thealgorithm{\thechapter.\arabic{algorithm}} 
\@addtoreset{algorithm}{chapter} 
\makeatother

\begin{document}

\chapter{chapter1}
\begin{algorithm}[H]
\centering
test
\caption{algo}
\label{algo1}
\end{algorithm}

\end{document}

enter image description here

If you really need both algorithm2e and algorithm in your document, and you want to use the algorithm environment (from the algorithm2e package), use the algorithm2e environment (the algo2e option renames algorithm to algorithm2e):

\documentclass[11pt]{book}
\usepackage[ruled,vlined,linesnumbered,algo2e,resetcount,algochapter]{algorithm2e}
\usepackage{algorithm}

\begin{document}

\chapter{chapter1}
\begin{algorithm2e}[H]
\centering
test
\caption{algo}
\label{algo1}
\end{algorithm2e}

\end{document}

enter image description here

By the way (not related to the question), you are loading packages more than once; this should be avoided.

Best Answer

Related Solutions

[Tex/LaTex] Restyling the caption in an algorithm created with algorithm2e

[Tex/LaTex] Algorithm with chapter number

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