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<a class="navbar-brand"><b>QuEST</b> v3.4.0<br>The Quantum Exact Simulation Toolkit</a>
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<p>Non-unitary but norm-preserving gates, such as measurements.
<a href="#details">More...</a></p>
<table class="memberdecls">
<tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="func-members"></a>
Functions</h2></td></tr>
<tr class="memitem:ga34457f7f62ccd75fb7d3fe67cd2f815a"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__type.html#ga7740e349b4f8bae6451547680f0ce2d6">qreal</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__normgate.html#ga34457f7f62ccd75fb7d3fe67cd2f815a">collapseToOutcome</a> (<a class="el" href="structQureg.html">Qureg</a> qureg, int measureQubit, int outcome)</td></tr>
<tr class="memdesc:ga34457f7f62ccd75fb7d3fe67cd2f815a"><td class="mdescLeft"> </td><td class="mdescRight">Updates <code>qureg</code> to be consistent with measuring <code>measureQubit</code> in the given <code>outcome</code> (0 or 1), and returns the probability of such a measurement outcome. <a href="group__normgate.html#ga34457f7f62ccd75fb7d3fe67cd2f815a">More...</a><br /></td></tr>
<tr class="separator:ga34457f7f62ccd75fb7d3fe67cd2f815a"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:ga2a3794103125f1e3cfa103f8b1963656"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group__normgate.html#ga2a3794103125f1e3cfa103f8b1963656">measure</a> (<a class="el" href="structQureg.html">Qureg</a> qureg, int measureQubit)</td></tr>
<tr class="memdesc:ga2a3794103125f1e3cfa103f8b1963656"><td class="mdescLeft"> </td><td class="mdescRight">Measures a single qubit, collapsing it randomly to 0 or 1. <a href="group__normgate.html#ga2a3794103125f1e3cfa103f8b1963656">More...</a><br /></td></tr>
<tr class="separator:ga2a3794103125f1e3cfa103f8b1963656"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:gae192ac0759e46c7b20a7182020155240"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group__normgate.html#gae192ac0759e46c7b20a7182020155240">measureWithStats</a> (<a class="el" href="structQureg.html">Qureg</a> qureg, int measureQubit, <a class="el" href="group__type.html#ga7740e349b4f8bae6451547680f0ce2d6">qreal</a> *outcomeProb)</td></tr>
<tr class="memdesc:gae192ac0759e46c7b20a7182020155240"><td class="mdescLeft"> </td><td class="mdescRight">Measures a single qubit, collapsing it randomly to 0 or 1, and additionally gives the probability of that outcome. <a href="group__normgate.html#gae192ac0759e46c7b20a7182020155240">More...</a><br /></td></tr>
<tr class="separator:gae192ac0759e46c7b20a7182020155240"><td class="memSeparator" colspan="2"> </td></tr>
</table>
<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<p>Non-unitary but norm-preserving gates, such as measurements. </p>
<h2 class="groupheader">Function Documentation</h2>
<a id="ga34457f7f62ccd75fb7d3fe67cd2f815a"></a>
<h2 class="memtitle"><span class="permalink"><a href="#ga34457f7f62ccd75fb7d3fe67cd2f815a">◆ </a></span>collapseToOutcome()</h2>
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<td class="memname"><a class="el" href="group__type.html#ga7740e349b4f8bae6451547680f0ce2d6">qreal</a> collapseToOutcome </td>
<td>(</td>
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<td class="paramname"><em>qureg</em>, </td>
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<td class="paramname"><em>measureQubit</em>, </td>
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<td class="paramtype">int </td>
<td class="paramname"><em>outcome</em> </td>
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<p>Updates <code>qureg</code> to be consistent with measuring <code>measureQubit</code> in the given <code>outcome</code> (0 or 1), and returns the probability of such a measurement outcome. </p>
<p>This is effectively performing a renormalising projection, or a measurement with a forced outcome. This is an irreversible change to the state, whereby computational states inconsistant with the outcome are given zero amplitude and the <code>qureg</code> is renormalised. The given outcome must not have a near zero probability, else it cannot be collapsed into.</p>
<p>Note that the collapse probably used for renormalisation is calculated for <code>outcome</code> <code>=</code> <code>0</code>, and assumed 1 minus this probability if <code>outcome</code> <code>=</code> <code>1</code>. Hence this routine will not correctly project un-normalised quregs onto <code>outcome</code> <code>=</code> <code>1</code>.</p>
<p>To avoid renormalisation after projection, or force projection into non-physical states with very small probability, use <a class="el" href="group__operator.html#ga26db8b8a8a242d388c291e50d228ab18" title="Force the target qubit of qureg into the given classical outcome, via a non-renormalising projection.">applyProjector()</a>.</p>
<dl class="section see"><dt>See also</dt><dd><ul>
<li><a class="el" href="group__normgate.html#ga2a3794103125f1e3cfa103f8b1963656" title="Measures a single qubit, collapsing it randomly to 0 or 1.">measure()</a></li>
<li><a class="el" href="group__normgate.html#gae192ac0759e46c7b20a7182020155240" title="Measures a single qubit, collapsing it randomly to 0 or 1, and additionally gives the probability of ...">measureWithStats()</a></li>
<li><a class="el" href="group__operator.html#ga26db8b8a8a242d388c291e50d228ab18" title="Force the target qubit of qureg into the given classical outcome, via a non-renormalising projection.">applyProjector()</a></li>
</ul>
</dd></dl>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">qureg</td><td>object representing the set of all qubits </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">measureQubit</td><td>qubit to measure </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">outcome</td><td>to force the measure qubit to enter </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>probability of the (forced) measurement outcome </dd></dl>
<dl class="exception"><dt>Exceptions</dt><dd>
<table class="exception">
<tr><td class="paramname"><a class="el" href="group__debug.html#ga51a64b05d31ef9bcf6a63ce26c0092db" title="An internal function called when invalid arguments are passed to a QuEST API call,...">invalidQuESTInputError()</a></td><td><ul>
<li>if <code>measureQubit</code> is outside [0, <code>qureg.numQubitsRepresented</code>)</li>
<li>if <code>outcome</code> is not in {0, 1}</li>
<li>if the probability of <code>outcome</code> is zero (within machine epsilon) </li>
</ul>
</td></tr>
</table>
</dd>
</dl>
<dl class="section author"><dt>Author</dt><dd>Ania Brown (state-vector) </dd>
<dd>
Tyson Jones (density matrix) </dd></dl>
<p class="definition">Definition at line <a class="el" href="QuEST_8c_source.html#l00966">966</a> of file <a class="el" href="QuEST_8c_source.html">QuEST.c</a>.</p>
<div class="fragment"><div class="line"><a name="l00966"></a><span class="lineno"> 966</span>  {</div>
<div class="line"><a name="l00967"></a><span class="lineno"> 967</span>  <a class="code" href="QuEST__validation_8c.html#ac31c45c5a31c523be0eb26abba6cf598">validateTarget</a>(qureg, measureQubit, __func__);</div>
<div class="line"><a name="l00968"></a><span class="lineno"> 968</span>  <a class="code" href="QuEST__validation_8c.html#ad613c75ff252a88e54f911053bd2032c">validateOutcome</a>(outcome, __func__);</div>
<div class="line"><a name="l00969"></a><span class="lineno"> 969</span>  </div>
<div class="line"><a name="l00970"></a><span class="lineno"> 970</span>  <a class="code" href="group__type.html#ga7740e349b4f8bae6451547680f0ce2d6">qreal</a> outcomeProb;</div>
<div class="line"><a name="l00971"></a><span class="lineno"> 971</span>  <span class="keywordflow">if</span> (qureg.<a class="code" href="structQureg.html#acf78445e9435d09f44f0cc832c6aee79">isDensityMatrix</a>) {</div>
<div class="line"><a name="l00972"></a><span class="lineno"> 972</span>  outcomeProb = <a class="code" href="QuEST__internal_8h.html#ae37b3eff5d3affbc1edfe216cabc1c53">densmatr_calcProbOfOutcome</a>(qureg, measureQubit, outcome);</div>
<div class="line"><a name="l00973"></a><span class="lineno"> 973</span>  <a class="code" href="QuEST__validation_8c.html#a8accabb8a9d573c2ff80305841c3053d">validateMeasurementProb</a>(outcomeProb, __func__);</div>
<div class="line"><a name="l00974"></a><span class="lineno"> 974</span>  <a class="code" href="QuEST__internal_8h.html#a5658f2ecbbd4ea425db5f7dc7fc4ba92">densmatr_collapseToKnownProbOutcome</a>(qureg, measureQubit, outcome, outcomeProb);</div>
<div class="line"><a name="l00975"></a><span class="lineno"> 975</span>  } <span class="keywordflow">else</span> {</div>
<div class="line"><a name="l00976"></a><span class="lineno"> 976</span>  outcomeProb = <a class="code" href="QuEST__internal_8h.html#a63cb88a5f4eb12fef087435b8db3f8eb">statevec_calcProbOfOutcome</a>(qureg, measureQubit, outcome);</div>
<div class="line"><a name="l00977"></a><span class="lineno"> 977</span>  <a class="code" href="QuEST__validation_8c.html#a8accabb8a9d573c2ff80305841c3053d">validateMeasurementProb</a>(outcomeProb, __func__);</div>
<div class="line"><a name="l00978"></a><span class="lineno"> 978</span>  <a class="code" href="QuEST__internal_8h.html#a008becc4a18f868340836e0ab9fd6df6">statevec_collapseToKnownProbOutcome</a>(qureg, measureQubit, outcome, outcomeProb);</div>
<div class="line"><a name="l00979"></a><span class="lineno"> 979</span>  }</div>
<div class="line"><a name="l00980"></a><span class="lineno"> 980</span>  </div>
<div class="line"><a name="l00981"></a><span class="lineno"> 981</span>  <a class="code" href="QuEST__qasm_8c.html#a0befde437a58ef8fe38495bfc2a16f0e">qasm_recordMeasurement</a>(qureg, measureQubit);</div>
<div class="line"><a name="l00982"></a><span class="lineno"> 982</span>  <span class="keywordflow">return</span> outcomeProb;</div>
<div class="line"><a name="l00983"></a><span class="lineno"> 983</span> }</div>
</div><!-- fragment -->
<p class="reference">References <a class="el" href="QuEST__cpu__distributed_8c_source.html#l01328">densmatr_calcProbOfOutcome()</a>, <a class="el" href="QuEST__cpu_8c_source.html#l00791">densmatr_collapseToKnownProbOutcome()</a>, <a class="el" href="QuEST_8h_source.html#l00325">Qureg::isDensityMatrix</a>, <a class="el" href="QuEST__qasm_8c_source.html#l00411">qasm_recordMeasurement()</a>, <a class="el" href="group__type.html#ga7740e349b4f8bae6451547680f0ce2d6">qreal</a>, <a class="el" href="QuEST__cpu__distributed_8c_source.html#l01312">statevec_calcProbOfOutcome()</a>, <a class="el" href="QuEST__cpu__distributed_8c_source.html#l01368">statevec_collapseToKnownProbOutcome()</a>, <a class="el" href="QuEST__validation_8c_source.html#l00527">validateMeasurementProb()</a>, <a class="el" href="QuEST__validation_8c_source.html#l00523">validateOutcome()</a>, and <a class="el" href="QuEST__validation_8c_source.html#l00400">validateTarget()</a>.</p>
<p class="reference">Referenced by <a class="el" href="test__gates_8cpp_source.html#l00015">TEST_CASE()</a>.</p>
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<a id="ga2a3794103125f1e3cfa103f8b1963656"></a>
<h2 class="memtitle"><span class="permalink"><a href="#ga2a3794103125f1e3cfa103f8b1963656">◆ </a></span>measure()</h2>
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<td class="memname">int measure </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structQureg.html">Qureg</a> </td>
<td class="paramname"><em>qureg</em>, </td>
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<td class="paramtype">int </td>
<td class="paramname"><em>measureQubit</em> </td>
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<p>Measures a single qubit, collapsing it randomly to 0 or 1. </p>
<p>Outcome probabilities are weighted by the state vector, which is irreversibly changed after collapse to be consistent with the outcome.</p>
<blockquote class="doxtable">
<p>The random outcome generator is seeded by <a class="el" href="group__debug.html#gae53fad7ebafccf236ad62b41e3244214" title="Seeds the random number generator with the (master node) current time and process ID.">seedQuESTDefault()</a> within <a class="el" href="group__type.html#ga8ba2c3388dd64d9348c3b091852d36d4" title="Create the QuEST execution environment.">createQuESTEnv()</a>, unless later overridden by <a class="el" href="group__debug.html#ga555451c697ea4a9d27389155f68fdabc" title="Seeds the random number generator with a custom array of key(s), overriding the default keys.">seedQuEST()</a>. </p>
</blockquote>
<dl class="section see"><dt>See also</dt><dd><ul>
<li><a class="el" href="group__normgate.html#gae192ac0759e46c7b20a7182020155240" title="Measures a single qubit, collapsing it randomly to 0 or 1, and additionally gives the probability of ...">measureWithStats()</a></li>
<li><a class="el" href="group__normgate.html#ga34457f7f62ccd75fb7d3fe67cd2f815a" title="Updates qureg to be consistent with measuring measureQubit in the given outcome (0 or 1),...">collapseToOutcome()</a></li>
<li><a class="el" href="group__debug.html#ga555451c697ea4a9d27389155f68fdabc" title="Seeds the random number generator with a custom array of key(s), overriding the default keys.">seedQuEST()</a></li>
<li><a class="el" href="group__debug.html#gae53fad7ebafccf236ad62b41e3244214" title="Seeds the random number generator with the (master node) current time and process ID.">seedQuESTDefault()</a></li>
</ul>
</dd></dl>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">qureg</td><td>object representing the set of all qubits </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">measureQubit</td><td>qubit to measure </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>the measurement outcome, 0 or 1 </dd></dl>
<dl class="exception"><dt>Exceptions</dt><dd>
<table class="exception">
<tr><td class="paramname"><a class="el" href="group__debug.html#ga51a64b05d31ef9bcf6a63ce26c0092db" title="An internal function called when invalid arguments are passed to a QuEST API call,...">invalidQuESTInputError()</a></td><td><ul>
<li>if <code>measureQubit</code> is outside [0, <code>qureg.numQubitsRepresented</code>) </li>
</ul>
</td></tr>
</table>
</dd>
</dl>
<dl class="section author"><dt>Author</dt><dd>Ania Brown (state-vector) </dd>
<dd>
Tyson Jones (density matrix) </dd></dl>
<p class="definition">Definition at line <a class="el" href="QuEST_8c_source.html#l00998">998</a> of file <a class="el" href="QuEST_8c_source.html">QuEST.c</a>.</p>
<div class="fragment"><div class="line"><a name="l00998"></a><span class="lineno"> 998</span>  {</div>
<div class="line"><a name="l00999"></a><span class="lineno"> 999</span>  <a class="code" href="QuEST__validation_8c.html#ac31c45c5a31c523be0eb26abba6cf598">validateTarget</a>(qureg, measureQubit, __func__);</div>
<div class="line"><a name="l01000"></a><span class="lineno"> 1000</span>  </div>
<div class="line"><a name="l01001"></a><span class="lineno"> 1001</span>  <span class="keywordtype">int</span> outcome;</div>
<div class="line"><a name="l01002"></a><span class="lineno"> 1002</span>  <a class="code" href="group__type.html#ga7740e349b4f8bae6451547680f0ce2d6">qreal</a> discardedProb;</div>
<div class="line"><a name="l01003"></a><span class="lineno"> 1003</span>  <span class="keywordflow">if</span> (qureg.<a class="code" href="structQureg.html#acf78445e9435d09f44f0cc832c6aee79">isDensityMatrix</a>)</div>
<div class="line"><a name="l01004"></a><span class="lineno"> 1004</span>  outcome = <a class="code" href="QuEST__common_8c.html#ae4ebc1f4dd48922bfb30ad1692310269">densmatr_measureWithStats</a>(qureg, measureQubit, &discardedProb);</div>
<div class="line"><a name="l01005"></a><span class="lineno"> 1005</span>  <span class="keywordflow">else</span></div>
<div class="line"><a name="l01006"></a><span class="lineno"> 1006</span>  outcome = <a class="code" href="QuEST__common_8c.html#ac2eb81c71d0e0fbec7be5b45b1db1448">statevec_measureWithStats</a>(qureg, measureQubit, &discardedProb);</div>
<div class="line"><a name="l01007"></a><span class="lineno"> 1007</span>  </div>
<div class="line"><a name="l01008"></a><span class="lineno"> 1008</span>  <a class="code" href="QuEST__qasm_8c.html#a0befde437a58ef8fe38495bfc2a16f0e">qasm_recordMeasurement</a>(qureg, measureQubit);</div>
<div class="line"><a name="l01009"></a><span class="lineno"> 1009</span>  <span class="keywordflow">return</span> outcome;</div>
<div class="line"><a name="l01010"></a><span class="lineno"> 1010</span> }</div>
</div><!-- fragment -->
<p class="reference">References <a class="el" href="QuEST__common_8c_source.html#l00372">densmatr_measureWithStats()</a>, <a class="el" href="QuEST_8h_source.html#l00325">Qureg::isDensityMatrix</a>, <a class="el" href="QuEST__qasm_8c_source.html#l00411">qasm_recordMeasurement()</a>, <a class="el" href="group__type.html#ga7740e349b4f8bae6451547680f0ce2d6">qreal</a>, <a class="el" href="QuEST__common_8c_source.html#l00364">statevec_measureWithStats()</a>, and <a class="el" href="QuEST__validation_8c_source.html#l00400">validateTarget()</a>.</p>
<p class="reference">Referenced by <a class="el" href="test__gates_8cpp_source.html#l00121">TEST_CASE()</a>.</p>
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<a id="gae192ac0759e46c7b20a7182020155240"></a>
<h2 class="memtitle"><span class="permalink"><a href="#gae192ac0759e46c7b20a7182020155240">◆ </a></span>measureWithStats()</h2>
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<td class="memname">int measureWithStats </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structQureg.html">Qureg</a> </td>
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<td class="paramname"><em>measureQubit</em>, </td>
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<td class="paramtype"><a class="el" href="group__type.html#ga7740e349b4f8bae6451547680f0ce2d6">qreal</a> * </td>
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<p>Measures a single qubit, collapsing it randomly to 0 or 1, and additionally gives the probability of that outcome. </p>
<p>Outcome probabilities are weighted by the state vector, which is irreversibly changed after collapse to be consistent with the outcome.</p>
<blockquote class="doxtable">
<p>The random outcome generator is seeded by <a class="el" href="group__debug.html#gae53fad7ebafccf236ad62b41e3244214" title="Seeds the random number generator with the (master node) current time and process ID.">seedQuESTDefault()</a> within <a class="el" href="group__type.html#ga8ba2c3388dd64d9348c3b091852d36d4" title="Create the QuEST execution environment.">createQuESTEnv()</a>, unless later overridden by <a class="el" href="group__debug.html#ga555451c697ea4a9d27389155f68fdabc" title="Seeds the random number generator with a custom array of key(s), overriding the default keys.">seedQuEST()</a>. </p>
</blockquote>
<dl class="section see"><dt>See also</dt><dd><ul>
<li><a class="el" href="group__normgate.html#ga2a3794103125f1e3cfa103f8b1963656" title="Measures a single qubit, collapsing it randomly to 0 or 1.">measure()</a></li>
<li><a class="el" href="group__normgate.html#ga34457f7f62ccd75fb7d3fe67cd2f815a" title="Updates qureg to be consistent with measuring measureQubit in the given outcome (0 or 1),...">collapseToOutcome()</a></li>
<li><a class="el" href="group__debug.html#gae53fad7ebafccf236ad62b41e3244214" title="Seeds the random number generator with the (master node) current time and process ID.">seedQuESTDefault()</a></li>
<li><a class="el" href="group__debug.html#ga555451c697ea4a9d27389155f68fdabc" title="Seeds the random number generator with a custom array of key(s), overriding the default keys.">seedQuEST()</a></li>
</ul>
</dd></dl>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">qureg</td><td>object representing the set of all qubits </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">measureQubit</td><td>qubit to measure </td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">outcomeProb</td><td>a pointer to a qreal which is set to the probability of the occurred outcome </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>the measurement outcome, 0 or 1 </dd></dl>
<dl class="exception"><dt>Exceptions</dt><dd>
<table class="exception">
<tr><td class="paramname"><a class="el" href="group__debug.html#ga51a64b05d31ef9bcf6a63ce26c0092db" title="An internal function called when invalid arguments are passed to a QuEST API call,...">invalidQuESTInputError()</a></td><td><ul>
<li>if <code>measureQubit</code> is outside [0, <code>qureg.numQubitsRepresented</code>) </li>
</ul>
</td></tr>
</table>
</dd>
</dl>
<dl class="section author"><dt>Author</dt><dd>Ania Brown (state-vector) </dd>
<dd>
Tyson Jones (density matrix) </dd></dl>
<p class="definition">Definition at line <a class="el" href="QuEST_8c_source.html#l00985">985</a> of file <a class="el" href="QuEST_8c_source.html">QuEST.c</a>.</p>
<div class="fragment"><div class="line"><a name="l00985"></a><span class="lineno"> 985</span>  {</div>
<div class="line"><a name="l00986"></a><span class="lineno"> 986</span>  <a class="code" href="QuEST__validation_8c.html#ac31c45c5a31c523be0eb26abba6cf598">validateTarget</a>(qureg, measureQubit, __func__);</div>
<div class="line"><a name="l00987"></a><span class="lineno"> 987</span>  </div>
<div class="line"><a name="l00988"></a><span class="lineno"> 988</span>  <span class="keywordtype">int</span> outcome;</div>
<div class="line"><a name="l00989"></a><span class="lineno"> 989</span>  <span class="keywordflow">if</span> (qureg.<a class="code" href="structQureg.html#acf78445e9435d09f44f0cc832c6aee79">isDensityMatrix</a>)</div>
<div class="line"><a name="l00990"></a><span class="lineno"> 990</span>  outcome = <a class="code" href="QuEST__common_8c.html#ae4ebc1f4dd48922bfb30ad1692310269">densmatr_measureWithStats</a>(qureg, measureQubit, outcomeProb);</div>
<div class="line"><a name="l00991"></a><span class="lineno"> 991</span>  <span class="keywordflow">else</span></div>
<div class="line"><a name="l00992"></a><span class="lineno"> 992</span>  outcome = <a class="code" href="QuEST__common_8c.html#ac2eb81c71d0e0fbec7be5b45b1db1448">statevec_measureWithStats</a>(qureg, measureQubit, outcomeProb);</div>
<div class="line"><a name="l00993"></a><span class="lineno"> 993</span>  </div>
<div class="line"><a name="l00994"></a><span class="lineno"> 994</span>  <a class="code" href="QuEST__qasm_8c.html#a0befde437a58ef8fe38495bfc2a16f0e">qasm_recordMeasurement</a>(qureg, measureQubit);</div>
<div class="line"><a name="l00995"></a><span class="lineno"> 995</span>  <span class="keywordflow">return</span> outcome;</div>
<div class="line"><a name="l00996"></a><span class="lineno"> 996</span> }</div>
</div><!-- fragment -->
<p class="reference">References <a class="el" href="QuEST__common_8c_source.html#l00372">densmatr_measureWithStats()</a>, <a class="el" href="QuEST_8h_source.html#l00325">Qureg::isDensityMatrix</a>, <a class="el" href="QuEST__qasm_8c_source.html#l00411">qasm_recordMeasurement()</a>, <a class="el" href="QuEST__common_8c_source.html#l00364">statevec_measureWithStats()</a>, and <a class="el" href="QuEST__validation_8c_source.html#l00400">validateTarget()</a>.</p>
<p class="reference">Referenced by <a class="el" href="test__gates_8cpp_source.html#l00213">TEST_CASE()</a>.</p>
</div>
</div>
</div><!-- contents -->
<div class="ttc" id="aQuEST__validation_8c_html_a8accabb8a9d573c2ff80305841c3053d"><div class="ttname"><a href="QuEST__validation_8c.html#a8accabb8a9d573c2ff80305841c3053d">validateMeasurementProb</a></div><div class="ttdeci">void validateMeasurementProb(qreal prob, const char *caller)</div><div class="ttdef"><b>Definition:</b> <a href="QuEST__validation_8c_source.html#l00527">QuEST_validation.c:527</a></div></div>
<div class="ttc" id="aQuEST__validation_8c_html_ac31c45c5a31c523be0eb26abba6cf598"><div class="ttname"><a href="QuEST__validation_8c.html#ac31c45c5a31c523be0eb26abba6cf598">validateTarget</a></div><div class="ttdeci">void validateTarget(Qureg qureg, int targetQubit, const char *caller)</div><div class="ttdef"><b>Definition:</b> <a href="QuEST__validation_8c_source.html#l00400">QuEST_validation.c:400</a></div></div>
<div class="ttc" id="aQuEST__validation_8c_html_ad613c75ff252a88e54f911053bd2032c"><div class="ttname"><a href="QuEST__validation_8c.html#ad613c75ff252a88e54f911053bd2032c">validateOutcome</a></div><div class="ttdeci">void validateOutcome(int outcome, const char *caller)</div><div class="ttdef"><b>Definition:</b> <a href="QuEST__validation_8c_source.html#l00523">QuEST_validation.c:523</a></div></div>
<div class="ttc" id="aQuEST__internal_8h_html_a63cb88a5f4eb12fef087435b8db3f8eb"><div class="ttname"><a href="QuEST__internal_8h.html#a63cb88a5f4eb12fef087435b8db3f8eb">statevec_calcProbOfOutcome</a></div><div class="ttdeci">qreal statevec_calcProbOfOutcome(Qureg qureg, int measureQubit, int outcome)</div><div class="ttdef"><b>Definition:</b> <a href="QuEST__cpu__distributed_8c_source.html#l01312">QuEST_cpu_distributed.c:1312</a></div></div>
<div class="ttc" id="agroup__type_html_ga7740e349b4f8bae6451547680f0ce2d6"><div class="ttname"><a href="group__type.html#ga7740e349b4f8bae6451547680f0ce2d6">qreal</a></div><div class="ttdeci">#define qreal</div></div>
<div class="ttc" id="aQuEST__internal_8h_html_a5658f2ecbbd4ea425db5f7dc7fc4ba92"><div class="ttname"><a href="QuEST__internal_8h.html#a5658f2ecbbd4ea425db5f7dc7fc4ba92">densmatr_collapseToKnownProbOutcome</a></div><div class="ttdeci">void densmatr_collapseToKnownProbOutcome(Qureg qureg, int measureQubit, int outcome, qreal outcomeProb)</div><div class="ttdoc">Renorms (/prob) every | * outcome * >< * outcome * | state, setting all others to zero.</div><div class="ttdef"><b>Definition:</b> <a href="QuEST__cpu_8c_source.html#l00791">QuEST_cpu.c:791</a></div></div>
<div class="ttc" id="aQuEST__qasm_8c_html_a0befde437a58ef8fe38495bfc2a16f0e"><div class="ttname"><a href="QuEST__qasm_8c.html#a0befde437a58ef8fe38495bfc2a16f0e">qasm_recordMeasurement</a></div><div class="ttdeci">void qasm_recordMeasurement(Qureg qureg, int measureQubit)</div><div class="ttdef"><b>Definition:</b> <a href="QuEST__qasm_8c_source.html#l00411">QuEST_qasm.c:411</a></div></div>
<div class="ttc" id="aQuEST__internal_8h_html_a008becc4a18f868340836e0ab9fd6df6"><div class="ttname"><a href="QuEST__internal_8h.html#a008becc4a18f868340836e0ab9fd6df6">statevec_collapseToKnownProbOutcome</a></div><div class="ttdeci">void statevec_collapseToKnownProbOutcome(Qureg qureg, int measureQubit, int outcome, qreal outcomeProb)</div><div class="ttdef"><b>Definition:</b> <a href="QuEST__cpu__distributed_8c_source.html#l01368">QuEST_cpu_distributed.c:1368</a></div></div>
<div class="ttc" id="aQuEST__common_8c_html_ac2eb81c71d0e0fbec7be5b45b1db1448"><div class="ttname"><a href="QuEST__common_8c.html#ac2eb81c71d0e0fbec7be5b45b1db1448">statevec_measureWithStats</a></div><div class="ttdeci">int statevec_measureWithStats(Qureg qureg, int measureQubit, qreal *outcomeProb)</div><div class="ttdef"><b>Definition:</b> <a href="QuEST__common_8c_source.html#l00364">QuEST_common.c:364</a></div></div>
<div class="ttc" id="astructQureg_html_acf78445e9435d09f44f0cc832c6aee79"><div class="ttname"><a href="structQureg.html#acf78445e9435d09f44f0cc832c6aee79">Qureg::isDensityMatrix</a></div><div class="ttdeci">int isDensityMatrix</div><div class="ttdoc">Whether this instance is a density-state representation.</div><div class="ttdef"><b>Definition:</b> <a href="QuEST_8h_source.html#l00325">QuEST.h:325</a></div></div>
<div class="ttc" id="aQuEST__internal_8h_html_ae37b3eff5d3affbc1edfe216cabc1c53"><div class="ttname"><a href="QuEST__internal_8h.html#ae37b3eff5d3affbc1edfe216cabc1c53">densmatr_calcProbOfOutcome</a></div><div class="ttdeci">qreal densmatr_calcProbOfOutcome(Qureg qureg, int measureQubit, int outcome)</div><div class="ttdef"><b>Definition:</b> <a href="QuEST__cpu__distributed_8c_source.html#l01328">QuEST_cpu_distributed.c:1328</a></div></div>
<div class="ttc" id="aQuEST__common_8c_html_ae4ebc1f4dd48922bfb30ad1692310269"><div class="ttname"><a href="QuEST__common_8c.html#ae4ebc1f4dd48922bfb30ad1692310269">densmatr_measureWithStats</a></div><div class="ttdeci">int densmatr_measureWithStats(Qureg qureg, int measureQubit, qreal *outcomeProb)</div><div class="ttdef"><b>Definition:</b> <a href="QuEST__common_8c_source.html#l00372">QuEST_common.c:372</a></div></div>
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