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<body id="top" lang="en">
<a name="Counters" class="anchor"></a>
<a name="Counters-1" class="anchor"></a>
<h2 class="chapter">Counters</h2>

<a name="index-counters_002c-a-list-of" class="anchor"></a>
<a name="index-variables_002c-a-list-of" class="anchor"></a>

<p>Everything LaTeX numbers for you has a counter associated with
it. The name of the counter is often the same as the name of the
environment or command associated with the number, except that the
counter&rsquo;s name has no backslash&nbsp;<code>\</code>.  Thus, associated with
the <code>\chapter</code> command is the <code>chapter</code> counter that keeps
track of the chapter number.  
</p>
<p>Below is a list of the counters used in LaTeX&rsquo;s standard document
classes to control numbering.
</p>
<div class="example">
<pre class="example">part            paragraph       figure          enumi
chapter         subparagraph    table           enumii
section         page            footnote        enumiii
subsection      equation        mpfootnote      enumiv
subsubsection
</pre></div>

<p>The <code>mpfootnote</code> counter is used by the <code>\footnote</code> command
inside of a minipage (see <a href="latex2e_8.html#minipage">minipage</a>).  The counters <code>enumi</code>
through <code>enumiv</code> are used in the <code>enumerate</code> environment, for
up to four levels of nesting (see <a href="latex2e_8.html#enumerate">enumerate</a>).
</p>
<p>Counters can have any integer value but they are typically positive.
</p>
<p>New counters are created with <code>\newcounter</code>.  See <a href="latex2e_12.html#g_t_005cnewcounter">\newcounter</a>.
</p>



<hr>
<a name="g_t_005calph-_005cAlph-_005carabic-_005croman-_005cRoman-_005cfnsymbol" class="anchor"></a>
<a name="g_t_005calph-_005cAlph-_005carabic-_005croman-_005cRoman-_005cfnsymbol_003a-Printing-counters" class="anchor"></a>
<h3 class="section"><code>\alph \Alph \arabic \roman \Roman \fnsymbol</code>: Printing counters</h3>

<a name="index-counters_002c-printing" class="anchor"></a>

<p>Print the value of a counter, in a specified style.  For instance, if
the counter <var>counter</var> has the value 1 then a
<code>\alph{<var>counter</var>}</code> in your source will result in a lowercase
letter&nbsp;a appearing in the output.
</p>
<p>All of these commands take a single counter as an argument, for
instance, <code>\alph{enumi}</code>.  Note that the counter name does not
start with a backslash.
</p>
<dl compact="compact">
<dt><code>\alph{<var>counter</var>}</code>
<a name="index-_005calph_007bcounter_007d" class="anchor"></a>
</dt>
<dd><p>Print the value of <var>counter</var> in lowercase letters: &lsquo;a&rsquo;, &lsquo;b&rsquo;,
<small class="enddots">...</small> If the counter&rsquo;s value is less than 1 or more than 26 then
you get &lsquo;<samp>LaTeX Error: Counter too large.</samp>&rsquo;
</p>
</dd>
<dt><code>\Alph{<var>counter</var>}</code>
<a name="index-_005cAlph_007bcounter_007d" class="anchor"></a>
</dt>
<dd><p>Print in uppercase letters: &lsquo;A&rsquo;, &lsquo;B&rsquo;, <small class="enddots">...</small> If the counter&rsquo;s value
is less than 1 or more than 26 then you get &lsquo;<samp>LaTeX Error: Counter
too large.</samp>&rsquo;
</p>
</dd>
<dt><code>\arabic{<var>counter</var>}</code>
<a name="index-_005carabic_007bcounter_007d" class="anchor"></a>
</dt>
<dd><p>Print in Arabic numbers such as &lsquo;<samp>5</samp>&rsquo; or &lsquo;<samp>-2</samp>&rsquo;.
</p>
</dd>
<dt><code>\roman{<var>counter</var>}</code>
<a name="index-_005croman_007bcounter_007d" class="anchor"></a>
</dt>
<dd><p>Print in lowercase roman numerals: &lsquo;i&rsquo;, &lsquo;ii&rsquo;, <small class="enddots">...</small> If the
counter&rsquo;s value is less than 1 then you get no warning or error but
LaTeX does not print anything in the output.
</p>
</dd>
<dt><code>\Roman{<var>counter</var>}</code>
<a name="index-_005cRoman_007bcounter_007d" class="anchor"></a>
</dt>
<dd><p>Print in uppercase roman numerals: &lsquo;I&rsquo;, &lsquo;II&rsquo;, <small class="enddots">...</small> If the
counter&rsquo;s value is less than 1 then you get no warning or error but
LaTeX does not print anything in the output.
</p>
</dd>
<dt><code>\fnsymbol{<var>counter</var>}</code>
<a name="index-_005cfnsymbol_007bcounter_007d" class="anchor"></a>
</dt>
<dd><p>Prints the value of <var>counter</var> using a sequence of nine symbols that
are traditionally used for labeling footnotes.  The value of
<var>counter</var> should be between&nbsp;1 and&nbsp;9, inclusive.  If the
counter&rsquo;s value is less than 0 or more than 9 then you get &lsquo;<samp>LaTeX
Error: Counter too large</samp>&rsquo;, while if it is 0 then you get no error or
warning but LaTeX does not output anything.
</p>
<p>Here are the symbols:
</p>
<table>
<thead><tr><th width="10%">Number</th><th width="30%">Name</th><th width="30%">Command</th><th width="30%">Symbol</th></tr></thead>
<tr><td width="10%">1</td><td width="30%">asterisk</td><td width="30%"><code>\ast</code></td><td width="30%">*</td></tr>
<tr><td width="10%">2</td><td width="30%">dagger</td><td width="30%"><code>\dagger</code></td><td width="30%">&#x2020;</td></tr>
<tr><td width="10%">3</td><td width="30%">ddagger</td><td width="30%"><code>\ddagger</code></td><td width="30%">&#x2021;</td></tr>
<tr><td width="10%">4</td><td width="30%">section-sign</td><td width="30%"><code>\S</code></td><td width="30%">&#x00A7;</td></tr>
<tr><td width="10%">5</td><td width="30%">paragraph-sign</td><td width="30%"><code>\P</code></td><td width="30%">&#x00B6;</td></tr>
<tr><td width="10%">6</td><td width="30%">double-vert</td><td width="30%"><code>\parallel</code></td><td width="30%">&#x2016;</td></tr>
<tr><td width="10%">7</td><td width="30%">double-asterisk</td><td width="30%"><code>\ast\ast</code></td><td width="30%">**</td></tr>
<tr><td width="10%">8</td><td width="30%">double-dagger</td><td width="30%"><code>\dagger\dagger</code></td><td width="30%">&#x2020;&#x2020;</td></tr>
<tr><td width="10%">9</td><td width="30%">double-ddagger</td><td width="30%"><code>\ddagger\ddagger</code></td><td width="30%">&#x2021;&#x2021;</td></tr>
</table>

</dd>
</dl>


<hr>
<a name="g_t_005cusecounter" class="anchor"></a>
<a name="g_t_005cusecounter-1" class="anchor"></a>
<h3 class="section"><code>\usecounter</code></h3>

<a name="index-_005cusecounter" class="anchor"></a>
<a name="index-list-items_002c-specifying-counter" class="anchor"></a>
<a name="index-numbered-items_002c-specifying-counter" class="anchor"></a>

<p>Synopsis:
</p>
<div class="example">
<pre class="example">\usecounter{<var>counter</var>}
</pre></div>

<p>Used in the second argument of the <code>list</code> environment
(see <a href="latex2e_8.html#list">list</a>), this declares that list items will be numbered by
<var>counter</var>.  It initializes <var>counter</var> to zero, and arranges that
when <code>\item</code> is called without its optional argument then
<var>counter</var> is incremented by <code>\refstepcounter</code>, making its value
be the current <code>ref</code> value (see <a href="latex2e_7.html#g_t_005cref">\ref</a>).  This command is fragile
(see <a href="latex2e_12.html#g_t_005cprotect">\protect</a>).
</p>
<p>Put in the document preamble, this example makes a new list environment
enumerated with <var>testcounter</var>:
</p>
<div class="example">
<pre class="example">\newcounter{testcounter}
\newenvironment{test}{%
  \begin{list}{}{%
    \usecounter{testcounter}
  }
}{%
  \end{list}
}
</pre></div>


<hr>
<a name="g_t_005cvalue" class="anchor"></a>
<a name="g_t_005cvalue-1" class="anchor"></a>
<h3 class="section"><code>\value</code></h3>

<a name="index-_005cvalue" class="anchor"></a>
<a name="index-counters_002c-getting-value-of" class="anchor"></a>

<p>Synopsis:
</p>
<div class="example">
<pre class="example">\value{<var>counter</var>}
</pre></div>

<p>Expands to the value of the counter <var>counter</var>. (Note that the name
of a counter does not begin with a backslash.)
</p>
<p>This example outputs &lsquo;<samp>Test counter is&nbsp;6. Other counter
is&nbsp;5.</samp>&rsquo;.
</p>
<div class="example">
<pre class="example">\newcounter{test} \setcounter{test}{5}
\newcounter{other} \setcounter{other}{\value{test}}
\addtocounter{test}{1}

Test counter is \arabic{test}.
Other counter is \arabic{other}.
</pre></div>

<p>The <code>\value</code> command is not used for typesetting the value of the
counter.  For that, see <a href="#g_t_005calph-_005cAlph-_005carabic-_005croman-_005cRoman-_005cfnsymbol">\alph \Alph \arabic \roman \Roman \fnsymbol</a>.
</p>
<p>It is often used in <code>\setcounter</code> or <code>\addtocounter</code> but
<code>\value</code> can be used anywhere that LaTeX expects a number, such
as in <code>\hspace{\value{foo}\parindent}</code>.  It must not be
preceded by <code>\protect</code> (see <a href="latex2e_12.html#g_t_005cprotect">\protect</a>).
</p>
<p>This example inserts <code>\hspace{4\parindent}</code>.
</p>
<div class="example">
<pre class="example">\setcounter{myctr}{3} \addtocounter{myctr}{1}
\hspace{\value{myctr}\parindent}
</pre></div>


<hr>
<a name="g_t_005csetcounter" class="anchor"></a>
<a name="g_t_005csetcounter-1" class="anchor"></a>
<h3 class="section"><code>\setcounter</code></h3>

<a name="index-_005csetcounter" class="anchor"></a>
<a name="index-counters_002c-setting" class="anchor"></a>
<a name="index-setting-counters" class="anchor"></a>

<p>Synopsis:
</p>
<div class="example">
<pre class="example">\setcounter{<var>counter</var>}{<var>value</var>}
</pre></div>

<p>Globally set the counter <var>counter</var> to have the value of the
<var>value</var> argument, which must be an integer.  Thus, you can set a
counter&rsquo;s value as <code>\setcounter{section}{5}</code>.  Note that the
counter name does not start with a backslash.
</p>
<p>In this example if the counter <code>theorem</code> has value 12 then the
second line will print &lsquo;<samp>XII</samp>&rsquo;.
</p>
<div class="example">
<pre class="example">\setcounter{exercise}{\value{theorem}}
Here it is in Roman: \Roman{exercise}.
</pre></div>


<hr>
<a name="g_t_005caddtocounter" class="anchor"></a>
<a name="g_t_005caddtocounter-1" class="anchor"></a>
<h3 class="section"><code>\addtocounter</code></h3>

<a name="index-_005caddtocounter" class="anchor"></a>

<p>Synopsis:
</p>
<div class="example">
<pre class="example">\addtocounter{<var>counter</var>}{<var>value</var>&nbsp;</pre></div>

<p>Globally increment <var>counter</var> by the amount specified by the
<var>value</var> argument, which may be negative.
</p>
<p>In this example the section value appears as &lsquo;<samp>VII</samp>&rsquo;.
</p>
<div class="example">
<pre class="example">\setcounter{section}{5}
\addtocounter{section}{2}
Here it is in Roman: \Roman{section}.
</pre></div>


<hr>
<a name="g_t_005crefstepcounter" class="anchor"></a>
<a name="g_t_005crefstepcounter-1" class="anchor"></a>
<h3 class="section"><code>\refstepcounter</code></h3>

<a name="index-_005crefstepcounter" class="anchor"></a>

<p>Synopsis:
</p>
<div class="example">
<pre class="example">\refstepcounter{<var>counter</var>}
</pre></div>

<p>Globally increments the value of <var>counter</var> by one, as does
<code>\stepcounter</code> (see <a href="#g_t_005cstepcounter">\stepcounter</a>).  The difference is that this
command resets the value of any counter numbered within it.  (For the
definition of &ldquo;counters numbered within&rdquo;, see <a href="latex2e_12.html#g_t_005cnewcounter">\newcounter</a>.)
</p>
<p>In addition, this command also defines the current <code>\ref</code> value
to be the result of <code>\thecounter</code>.
</p>
<p>While the counter value is set globally, the <code>\ref</code> value is set
locally, i.e., inside the current group.
</p>

<hr>
<a name="g_t_005cstepcounter" class="anchor"></a>
<a name="g_t_005cstepcounter-1" class="anchor"></a>
<h3 class="section"><code>\stepcounter</code></h3>

<a name="index-_005cstepcounter" class="anchor"></a>

<p>Synopsis:
</p>
<div class="example">
<pre class="example">\stepcounter{<var>counter</var>}
</pre></div>

<p>Globally adds one to <var>counter</var> and resets all counters numbered
within it.  (For the definition of &ldquo;counters numbered within&rdquo;,
see <a href="latex2e_12.html#g_t_005cnewcounter">\newcounter</a>.)
</p>
<p>This command differs from <code>\refstepcounter</code> in that this one does
not influence references&nbsp;&mdash; it does not define the current
<code>\ref</code> value to be the result of <code>\thecounter</code>
(see <a href="#g_t_005crefstepcounter">\refstepcounter</a>).
</p>

<hr>
<a name="g_t_005cday-_0026-_005cmonth-_0026-_005cyear" class="anchor"></a>
<a name="g_t_005cday-_0026-_005cmonth-_0026-_005cyear-1" class="anchor"></a>
<h3 class="section"><code>\day</code> &amp; <code>\month</code> &amp; <code>\year</code></h3>

<a name="index-_005cday" class="anchor"></a>
<a name="index-_005cmonth" class="anchor"></a>
<a name="index-_005cyear" class="anchor"></a>

<p>LaTeX defines the counter <code>\day</code> for the day of the month
(nominally with value between 1 and 31), <code>\month</code> for the month of
the year (nominally with value between 1 and 12), and year <code>\year</code>.
When TeX starts up, they are set from the current values on the
system.  The related command <code>\today</code> produces a string
representing the current day (see <a href="latex2e_23.html#g_t_005ctoday">\today</a>).
</p>
<p>They counters are not updated as the job progresses so in principle they
could be incorrect by the end.  In addition, TeX does no sanity
check:
</p>
<div class="example">
<pre class="example">\day=-2 \month=13 \year=-4 \today
</pre></div>

<p>gives no error or warning and results in the output &lsquo;<samp>-2, -4</samp>&rsquo; (the
bogus month value produces no output).
</p>




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