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We also 0016 gratefully acknowledge additional material appearing in 0017 latex2e-reference by Martin Herbert Dietze. (From these references no 0018 text was directly copied.) 0019 0020 Copyright 2007, 2008, 2009, 2010, 2011, 2012, 2013, 0021 2014, 2015, 2016, 2017, 2018 Karl Berry. 0022 0023 Copyright 1988, 1994, 2007 Stephen Gilmore. 0024 0025 Copyright 1994, 1995, 1996 Torsten Martinsen. 0026 0027 Permission is granted to make and distribute verbatim copies of 0028 this manual provided the copyright notice and this permission notice 0029 are preserved on all copies. 0030 0031 0032 Permission is granted to copy and distribute modified versions of this 0033 manual under the conditions for verbatim copying, provided that the entire 0034 resulting derived work is distributed under the terms of a permission 0035 notice identical to this one. 0036 0037 Permission is granted to copy and distribute translations of this manual 0038 into another language, under the above conditions for modified versions. --> 0039 <!-- Created by GNU Texinfo 6.5, http://www.gnu.org/software/texinfo/ --> 0040 <head> 0041 <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 0042 <title>\label (LaTeX2e unofficial reference manual (November 2018))</title> 0043 0044 <meta name="description" content="\label (LaTeX2e unofficial reference manual (November 2018))"> 0045 <meta name="keywords" content="\label (LaTeX2e unofficial reference manual (November 2018))"> 0046 <meta name="resource-type" content="document"> 0047 <meta name="distribution" content="global"> 0048 <meta name="Generator" content="makeinfo"> 0049 <link href="index.html#Top" rel="start" title="Top"> 0050 <link href="IndexDocument.html#Index" rel="index" title="Index"> 0051 <link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> 0052 <link href="Cross-references.html#Cross-references" rel="up" title="Cross references"> 0053 <link href="_005cpageref.html#g_t_005cpageref" rel="next" title="\pageref"> 0054 <link href="Cross-references.html#Cross-references" rel="prev" title="Cross references"> 0055 <style type="text/css"> 0056 <!-- 0057 /* $Id: latex2e.css 690 2018-09-15 15:20:19Z jimhefferon $ 0058 Minor css for latexrefman. 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In ordinary text 0131 <code>\label{<var>key</var>}</code> assigns to <var>key</var> the number of the 0132 current sectional unit. Inside an environment with numbering, such as a 0133 <code>table</code> or <code>theorem</code> environment, <code>\label{<var>key</var>}</code> 0134 assigns to <var>key</var> the number of that environment. Retrieve the 0135 assigned number with the <code>\ref{<var>key</var>}</code> command 0136 (see <a href="_005cref.html#g_t_005cref">\ref</a>). 0137 </p> 0138 <p>A key name can consist of any sequence of letters, digits, or common 0139 punctuation characters. Upper and lowercase letters are 0140 distinguished, as usual. 0141 </p> 0142 <p>A common convention is to use labels consisting of a prefix and a suffix 0143 separated by a colon or period. Thus, <code>\label{fig:Post}</code> is a 0144 label for a figure with a portrait of Emil Post. This helps to avoid 0145 accidentally creating two labels with the same name, and makes your 0146 source more readable. Some commonly-used prefixes: 0147 </p> 0148 <dl compact="compact"> 0149 <dt><code>ch</code></dt> 0150 <dd><p>for chapters 0151 </p> 0152 </dd> 0153 <dt><code>sec</code></dt> 0154 <dt><code>subsec</code></dt> 0155 <dd><p>for lower-level sectioning commands 0156 </p> 0157 </dd> 0158 <dt><code>fig</code></dt> 0159 <dd><p>for figures 0160 </p> 0161 </dd> 0162 <dt><code>tab</code></dt> 0163 <dd><p>for tables 0164 </p> 0165 </dd> 0166 <dt><code>eq</code></dt> 0167 <dd><p>for equations 0168 </p></dd> 0169 </dl> 0170 0171 <p>In the auxiliary file the reference information is kept as the text of 0172 a command of the form 0173 <code>\newlabel{<var>label</var>}{{<var>currentlabel</var>}{<var>pagenumber</var>}}</code>. 0174 Here <var>currentlabel</var> is the current value of the macro 0175 <code>\@currentlabel</code> that is usually updated whenever you call 0176 <code>\refstepcounter{<var>counter</var>}</code>. 0177 </p> 0178 <p>Below, the key <code>sec:test</code> will get the number of the current 0179 section and the key <code>fig:test</code> will get the number of the figure. 0180 (Incidentally, put labels after captions in figures and tables.) 0181 </p> 0182 <div class="example"> 0183 <pre class="example">\section{section name} 0184 \label{sec:test} 0185 This is Section~\ref{sec:test}. 0186 \begin{figure} 0187 ... 0188 \caption{caption text} 0189 \label{fig:test} 0190 \end{figure} 0191 See Figure~\ref{fig:test}. 0192 </pre></div> 0193 0194 0195 0196 0197 <hr/><div class='referenceinfo'> <a href='https://latexref.xyz/'> <i>Unofficial LaTeX2e reference manual</i></a></div> 0198 </body> 0199 </html>