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<title>Class template quantity<BOOST_UNITS_DIMENSIONLESS_UNIT(System), Y></title>
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<h2><span class="refentrytitle">Class template quantity<BOOST_UNITS_DIMENSIONLESS_UNIT(System), Y></span></h2>
<p>boost::units::quantity<BOOST_UNITS_DIMENSIONLESS_UNIT(System), Y></p>
</div>
<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2>
<div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: <<a class="link" href="../../boost_units/Reference.html#header.boost.units.quantity_hpp" title="Header <boost/units/quantity.hpp>">boost/units/quantity.hpp</a>>
</span><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> System<span class="special">,</span> <span class="keyword">typename</span> Y<span class="special">></span>
<span class="keyword">class</span> <a class="link" href="quantity_idm45506851440432.html" title="Class template quantity<BOOST_UNITS_DIMENSIONLESS_UNIT(System), Y>">quantity</a><span class="special"><</span><span class="identifier">BOOST_UNITS_DIMENSIONLESS_UNIT</span><span class="special">(</span><span class="identifier">System</span><span class="special">)</span><span class="special">,</span> <span class="identifier">Y</span><span class="special">></span> <span class="special">{</span>
<span class="keyword">public</span><span class="special">:</span>
<span class="comment">// types</span>
<span class="keyword">typedef</span> <a class="link" href="quantity.html" title="Class template quantity">quantity</a><span class="special"><</span> <a class="link" href="unit.html" title="Class template unit">unit</a><span class="special"><</span> <a class="link" href="dimensionless_type.html" title="Struct dimensionless_type">dimensionless_type</a><span class="special">,</span> <span class="identifier">System</span> <span class="special">></span><span class="special">,</span> <span class="identifier">Y</span> <span class="special">></span> <a name="boost.units.quantity_idm45506851440432.this_type"></a><span class="identifier">this_type</span><span class="special">;</span>
<span class="keyword">typedef</span> <span class="identifier">Y</span> <a name="boost.units.quantity_idm45506851440432.value_type"></a><span class="identifier">value_type</span><span class="special">;</span>
<span class="keyword">typedef</span> <span class="identifier">System</span> <a name="boost.units.quantity_idm45506851440432.system_type"></a><span class="identifier">system_type</span><span class="special">;</span>
<span class="keyword">typedef</span> <a class="link" href="dimensionless_type.html" title="Struct dimensionless_type">dimensionless_type</a> <a name="boost.units.quantity_idm45506851440432.dimension_type"></a><span class="identifier">dimension_type</span><span class="special">;</span>
<span class="keyword">typedef</span> <a class="link" href="unit.html" title="Class template unit">unit</a><span class="special"><</span> <span class="identifier">dimension_type</span><span class="special">,</span> <span class="identifier">system_type</span> <span class="special">></span> <a name="boost.units.quantity_idm45506851440432.unit_type"></a><span class="identifier">unit_type</span><span class="special">;</span>
<span class="comment">// <a class="link" href="quantity_idm45506851440432.html#boost.units.quantity_idm45506851440432construct-copy-destruct">construct/copy/destruct</a></span>
<a class="link" href="quantity_idm45506851440432.html#idm45506851419136-bb"><span class="identifier">quantity</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span>
<a class="link" href="quantity_idm45506851440432.html#idm45506851418848-bb"><span class="identifier">quantity</span></a><span class="special">(</span><span class="identifier">value_type</span><span class="special">)</span><span class="special">;</span>
<a class="link" href="quantity_idm45506851440432.html#idm45506851417136-bb"><span class="identifier">quantity</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">this_type</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span>
<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> YY<span class="special">></span>
<a class="link" href="quantity_idm45506851440432.html#idm45506851414896-bb"><span class="identifier">quantity</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="quantity.html" title="Class template quantity">quantity</a><span class="special"><</span> <a class="link" href="unit.html" title="Class template unit">unit</a><span class="special"><</span> <span class="identifier">dimension_type</span><span class="special">,</span> <span class="identifier">system_type</span> <span class="special">></span><span class="special">,</span> <span class="identifier">YY</span> <span class="special">></span> <span class="special">&</span><span class="special">,</span>
<span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">)</span><span class="special">;</span>
<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> YY<span class="special">></span>
<span class="keyword">explicit</span> <a class="link" href="quantity_idm45506851440432.html#idm45506851410688-bb"><span class="identifier">quantity</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="quantity.html" title="Class template quantity">quantity</a><span class="special"><</span> <a class="link" href="unit.html" title="Class template unit">unit</a><span class="special"><</span> <span class="identifier">dimension_type</span><span class="special">,</span> <span class="identifier">system_type</span> <span class="special">></span><span class="special">,</span> <span class="identifier">YY</span> <span class="special">></span> <span class="special">&</span><span class="special">,</span>
<span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">)</span><span class="special">;</span>
<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> System2<span class="special">,</span> <span class="keyword">typename</span> Y2<span class="special">></span>
<a class="link" href="quantity_idm45506851440432.html#idm45506851402816-bb"><span class="identifier">quantity</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="quantity.html" title="Class template quantity">quantity</a><span class="special"><</span> <a class="link" href="unit.html" title="Class template unit">unit</a><span class="special"><</span> <a class="link" href="dimensionless_type.html" title="Struct dimensionless_type">dimensionless_type</a><span class="special">,</span> <span class="identifier">System2</span> <span class="special">></span><span class="special">,</span> <span class="identifier">Y2</span> <span class="special">></span> <span class="special">&</span><span class="special">,</span>
<span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">,</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">,</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">)</span><span class="special">;</span>
<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> System2<span class="special">,</span> <span class="keyword">typename</span> Y2<span class="special">></span>
<span class="keyword">explicit</span> <a class="link" href="quantity_idm45506851440432.html#idm45506851395440-bb"><span class="identifier">quantity</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="quantity.html" title="Class template quantity">quantity</a><span class="special"><</span> <a class="link" href="unit.html" title="Class template unit">unit</a><span class="special"><</span> <a class="link" href="dimensionless_type.html" title="Struct dimensionless_type">dimensionless_type</a><span class="special">,</span> <span class="identifier">System2</span> <span class="special">></span><span class="special">,</span> <span class="identifier">Y2</span> <span class="special">></span> <span class="special">&</span><span class="special">,</span>
<span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">,</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">,</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">)</span><span class="special">;</span>
<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> System2<span class="special">,</span> <span class="keyword">typename</span> Y2<span class="special">></span>
<span class="keyword">explicit</span> <a class="link" href="quantity_idm45506851440432.html#idm45506851387792-bb"><span class="identifier">quantity</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="quantity.html" title="Class template quantity">quantity</a><span class="special"><</span> <a class="link" href="unit.html" title="Class template unit">unit</a><span class="special"><</span> <a class="link" href="dimensionless_type.html" title="Struct dimensionless_type">dimensionless_type</a><span class="special">,</span> <span class="identifier">System2</span> <span class="special">></span><span class="special">,</span> <span class="identifier">Y2</span> <span class="special">></span> <span class="special">&</span><span class="special">,</span>
<span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">)</span><span class="special">;</span>
<span class="identifier">this_type</span> <span class="special">&</span> <a class="link" href="quantity_idm45506851440432.html#idm45506851416160-bb"><span class="keyword">operator</span><span class="special">=</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">this_type</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span>
<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> YY<span class="special">></span>
<span class="identifier">this_type</span> <span class="special">&</span> <a class="link" href="quantity_idm45506851440432.html#idm45506851406208-bb"><span class="keyword">operator</span><span class="special">=</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="quantity.html" title="Class template quantity">quantity</a><span class="special"><</span> <a class="link" href="unit.html" title="Class template unit">unit</a><span class="special"><</span> <span class="identifier">dimension_type</span><span class="special">,</span> <span class="identifier">system_type</span> <span class="special">></span><span class="special">,</span> <span class="identifier">YY</span> <span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span>
<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> System2<span class="special">></span>
<span class="identifier">this_type</span> <span class="special">&</span> <a class="link" href="quantity_idm45506851440432.html#idm45506851382192-bb"><span class="keyword">operator</span><span class="special">=</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="quantity.html" title="Class template quantity">quantity</a><span class="special"><</span> <span class="identifier">BOOST_UNITS_DIMENSIONLESS_UNIT</span><span class="special">(</span><span class="identifier">System2</span><span class="special">)</span><span class="special">,</span> <span class="identifier">Y</span> <span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span>
<span class="comment">// <a class="link" href="quantity_idm45506851440432.html#idm45506851430992-bb">public member functions</a></span>
<a class="link" href="quantity_idm45506851440432.html#idm45506851430432-bb"><span class="keyword">operator</span> <span class="identifier">value_type</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
<span class="keyword">const</span> <span class="identifier">value_type</span> <span class="special">&</span> <a class="link" href="quantity_idm45506851440432.html#idm45506851428576-bb"><span class="identifier">value</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
<span class="identifier">this_type</span> <span class="special">&</span> <a class="link" href="quantity_idm45506851440432.html#idm45506851426640-bb"><span class="keyword">operator</span><span class="special">+=</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">this_type</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span>
<span class="identifier">this_type</span> <span class="special">&</span> <a class="link" href="quantity_idm45506851440432.html#idm45506851424704-bb"><span class="keyword">operator</span><span class="special">-=</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">this_type</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span>
<span class="identifier">this_type</span> <span class="special">&</span> <a class="link" href="quantity_idm45506851440432.html#idm45506851422768-bb"><span class="keyword">operator</span><span class="special">*=</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">value_type</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span>
<span class="identifier">this_type</span> <span class="special">&</span> <a class="link" href="quantity_idm45506851440432.html#idm45506851420832-bb"><span class="keyword">operator</span><span class="special">/=</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">value_type</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span>
<span class="comment">// <a class="link" href="quantity_idm45506851440432.html#idm45506851379264-bb">public static functions</a></span>
<span class="keyword">static</span> <span class="identifier">this_type</span> <a class="link" href="quantity_idm45506851440432.html#idm45506851378704-bb"><span class="identifier">from_value</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">value_type</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span>
<span class="special">}</span><span class="special">;</span></pre></div>
<div class="refsect1">
<a name="idm45555056810224"></a><h2>Description</h2>
<p>Specialization for dimensionless quantities. Implicit conversions between unit systems are allowed because all dimensionless quantities are equivalent. Implicit construction and assignment from and conversion to <code class="computeroutput">value_type</code> is also allowed. </p>
<div class="refsect2">
<a name="idm45555056808608"></a><h3>
<a name="boost.units.quantity_idm45506851440432construct-copy-destruct"></a><code class="computeroutput">quantity</code>
public
construct/copy/destruct</h3>
<div class="orderedlist"><ol class="orderedlist" type="1">
<li class="listitem"><pre class="literallayout"><a name="idm45506851419136-bb"></a><span class="identifier">quantity</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre></li>
<li class="listitem">
<pre class="literallayout"><a name="idm45506851418848-bb"></a><span class="identifier">quantity</span><span class="special">(</span><span class="identifier">value_type</span> val<span class="special">)</span><span class="special">;</span></pre>construction from raw <code class="computeroutput">value_type</code> is allowed </li>
<li class="listitem"><pre class="literallayout"><a name="idm45506851417136-bb"></a><span class="identifier">quantity</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">this_type</span> <span class="special">&</span> source<span class="special">)</span><span class="special">;</span></pre></li>
<li class="listitem">
<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> YY<span class="special">></span>
<a name="idm45506851414896-bb"></a><span class="identifier">quantity</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="quantity.html" title="Class template quantity">quantity</a><span class="special"><</span> <a class="link" href="unit.html" title="Class template unit">unit</a><span class="special"><</span> <span class="identifier">dimension_type</span><span class="special">,</span> <span class="identifier">system_type</span> <span class="special">></span><span class="special">,</span> <span class="identifier">YY</span> <span class="special">></span> <span class="special">&</span> source<span class="special">,</span>
<span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">)</span><span class="special">;</span></pre>implicit conversion between value types is allowed if allowed for value types themselves </li>
<li class="listitem">
<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> YY<span class="special">></span>
<span class="keyword">explicit</span> <a name="idm45506851410688-bb"></a><span class="identifier">quantity</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="quantity.html" title="Class template quantity">quantity</a><span class="special"><</span> <a class="link" href="unit.html" title="Class template unit">unit</a><span class="special"><</span> <span class="identifier">dimension_type</span><span class="special">,</span> <span class="identifier">system_type</span> <span class="special">></span><span class="special">,</span> <span class="identifier">YY</span> <span class="special">></span> <span class="special">&</span> source<span class="special">,</span>
<span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">)</span><span class="special">;</span></pre>implicit conversion between value types is not allowed if not allowed for value types themselves </li>
<li class="listitem">
<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> System2<span class="special">,</span> <span class="keyword">typename</span> Y2<span class="special">></span>
<a name="idm45506851402816-bb"></a><span class="identifier">quantity</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="quantity.html" title="Class template quantity">quantity</a><span class="special"><</span> <a class="link" href="unit.html" title="Class template unit">unit</a><span class="special"><</span> <a class="link" href="dimensionless_type.html" title="Struct dimensionless_type">dimensionless_type</a><span class="special">,</span> <span class="identifier">System2</span> <span class="special">></span><span class="special">,</span> <span class="identifier">Y2</span> <span class="special">></span> <span class="special">&</span> source<span class="special">,</span>
<span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">,</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">,</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">)</span><span class="special">;</span></pre>implicit conversion between different unit systems is allowed </li>
<li class="listitem">
<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> System2<span class="special">,</span> <span class="keyword">typename</span> Y2<span class="special">></span>
<span class="keyword">explicit</span> <a name="idm45506851395440-bb"></a><span class="identifier">quantity</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="quantity.html" title="Class template quantity">quantity</a><span class="special"><</span> <a class="link" href="unit.html" title="Class template unit">unit</a><span class="special"><</span> <a class="link" href="dimensionless_type.html" title="Struct dimensionless_type">dimensionless_type</a><span class="special">,</span> <span class="identifier">System2</span> <span class="special">></span><span class="special">,</span> <span class="identifier">Y2</span> <span class="special">></span> <span class="special">&</span> source<span class="special">,</span>
<span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">,</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">,</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">)</span><span class="special">;</span></pre>implicit conversion between different unit systems is allowed </li>
<li class="listitem">
<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> System2<span class="special">,</span> <span class="keyword">typename</span> Y2<span class="special">></span>
<span class="keyword">explicit</span> <a name="idm45506851387792-bb"></a><span class="identifier">quantity</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="quantity.html" title="Class template quantity">quantity</a><span class="special"><</span> <a class="link" href="unit.html" title="Class template unit">unit</a><span class="special"><</span> <a class="link" href="dimensionless_type.html" title="Struct dimensionless_type">dimensionless_type</a><span class="special">,</span> <span class="identifier">System2</span> <span class="special">></span><span class="special">,</span> <span class="identifier">Y2</span> <span class="special">></span> <span class="special">&</span> source<span class="special">,</span>
<span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="special">=</span> <span class="number">0</span><span class="special">)</span><span class="special">;</span></pre>
<p>conversion between different unit systems is explicit when the units are not equivalent. </p>
</li>
<li class="listitem"><pre class="literallayout"><span class="identifier">this_type</span> <span class="special">&</span> <a name="idm45506851416160-bb"></a><span class="keyword">operator</span><span class="special">=</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">this_type</span> <span class="special">&</span> source<span class="special">)</span><span class="special">;</span></pre></li>
<li class="listitem">
<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> YY<span class="special">></span>
<span class="identifier">this_type</span> <span class="special">&</span> <a name="idm45506851406208-bb"></a><span class="keyword">operator</span><span class="special">=</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="quantity.html" title="Class template quantity">quantity</a><span class="special"><</span> <a class="link" href="unit.html" title="Class template unit">unit</a><span class="special"><</span> <span class="identifier">dimension_type</span><span class="special">,</span> <span class="identifier">system_type</span> <span class="special">></span><span class="special">,</span> <span class="identifier">YY</span> <span class="special">></span> <span class="special">&</span> source<span class="special">)</span><span class="special">;</span></pre>implicit assignment between value types is allowed if allowed for value types themselves </li>
<li class="listitem">
<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> System2<span class="special">></span>
<span class="identifier">this_type</span> <span class="special">&</span> <a name="idm45506851382192-bb"></a><span class="keyword">operator</span><span class="special">=</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="quantity.html" title="Class template quantity">quantity</a><span class="special"><</span> <span class="identifier">BOOST_UNITS_DIMENSIONLESS_UNIT</span><span class="special">(</span><span class="identifier">System2</span><span class="special">)</span><span class="special">,</span> <span class="identifier">Y</span> <span class="special">></span> <span class="special">&</span> source<span class="special">)</span><span class="special">;</span></pre>implicit assignment between different unit systems is allowed </li>
</ol></div>
</div>
<div class="refsect2">
<a name="idm45555056646800"></a><h3>
<a name="idm45506851430992-bb"></a><code class="computeroutput">quantity</code> public member functions</h3>
<div class="orderedlist"><ol class="orderedlist" type="1">
<li class="listitem">
<pre class="literallayout"><a name="idm45506851430432-bb"></a><span class="keyword">operator</span> <span class="identifier">value_type</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre>implicit conversion to <code class="computeroutput">value_type</code> is allowed </li>
<li class="listitem">
<pre class="literallayout"><span class="keyword">const</span> <span class="identifier">value_type</span> <span class="special">&</span> <a name="idm45506851428576-bb"></a><span class="identifier">value</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre>constant accessor to value <p>can add a quantity of the same type if add_typeof_helper<value_type,value_type>::type is convertible to value_type </p>
</li>
<li class="listitem">
<pre class="literallayout"><span class="identifier">this_type</span> <span class="special">&</span> <a name="idm45506851426640-bb"></a><span class="keyword">operator</span><span class="special">+=</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">this_type</span> <span class="special">&</span> source<span class="special">)</span><span class="special">;</span></pre>can subtract a quantity of the same type if subtract_typeof_helper<value_type,value_type>::type is convertible to value_type </li>
<li class="listitem">
<pre class="literallayout"><span class="identifier">this_type</span> <span class="special">&</span> <a name="idm45506851424704-bb"></a><span class="keyword">operator</span><span class="special">-=</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">this_type</span> <span class="special">&</span> source<span class="special">)</span><span class="special">;</span></pre>can multiply a quantity by a scalar value_type if multiply_typeof_helper<value_type,value_type>::type is convertible to value_type </li>
<li class="listitem">
<pre class="literallayout"><span class="identifier">this_type</span> <span class="special">&</span> <a name="idm45506851422768-bb"></a><span class="keyword">operator</span><span class="special">*=</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">value_type</span> <span class="special">&</span> val<span class="special">)</span><span class="special">;</span></pre>can divide a quantity by a scalar value_type if divide_typeof_helper<value_type,value_type>::type is convertible to value_type </li>
<li class="listitem"><pre class="literallayout"><span class="identifier">this_type</span> <span class="special">&</span> <a name="idm45506851420832-bb"></a><span class="keyword">operator</span><span class="special">/=</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">value_type</span> <span class="special">&</span> val<span class="special">)</span><span class="special">;</span></pre></li>
</ol></div>
</div>
<div class="refsect2">
<a name="idm45555056600496"></a><h3>
<a name="idm45506851379264-bb"></a><code class="computeroutput">quantity</code> public static functions</h3>
<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem">
<pre class="literallayout"><span class="keyword">static</span> <span class="identifier">this_type</span> <a name="idm45506851378704-bb"></a><span class="identifier">from_value</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">value_type</span> <span class="special">&</span> val<span class="special">)</span><span class="special">;</span></pre>Construct quantity directly from <code class="computeroutput">value_type</code>. </li></ol></div>
</div>
</div>
</div>
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<td align="right"><div class="copyright-footer">Copyright © 2003-2008 Matthias Christian Schabel<br>Copyright © 2007-2010 Steven
Watanabe<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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