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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::indirect_array&lt;T&gt;::</span>operator=</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-numeric.html">numeric</a>&lrm; | <a href="cpp-numeric-valarray.html">valarray</a>&lrm; | <a href="cpp-numeric-valarray-indirect_array.html">indirect array</a></span></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span> operator<span class="sy1">=</span><span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&amp;</span> value <span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span></span></div>
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<td>(1)</td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span> operator<span class="sy1">=</span><span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-numeric-valarray.html"><span class="kw1473">std::<span class="me2">valarray</span></span></a><span class="sy1">&lt;</span>T<span class="sy1">&gt;</span><span class="sy3">&amp;</span> val_arr <span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span></span></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">const</span> indirect_array<span class="sy3">&amp;</span> operator<span class="sy1">=</span><span class="br0">(</span> <span class="kw4">const</span> indirect_array<span class="sy3">&amp;</span> sl_arr<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></td>
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<p>&#23558;&#20540;&#36171;&#20540;&#32473;&#25152;&#26377;&#34987;&#24341;&#29992;&#20803;&#32032;&#12290;</p>
<div class="t-li1"><span class="t-li">1)</span> &#23558; <code>value</code> &#36171;&#20540;&#32473;&#25152;&#26377;&#20803;&#32032;&#12290;</div>
<div class="t-li1"><span class="t-li">2)</span> &#23558; <code>val_arr</code> &#30340;&#20803;&#32032;&#36171;&#20540;&#32473; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span> &#25152;&#24341;&#29992;&#30340;&#20803;&#32032;&#12290;</div>
<div class="t-li1"><span class="t-li">3)</span> &#23558;&#33258; <code>sl_arr</code> &#36873;&#25321;&#30340;&#20803;&#32032;&#36171;&#20540;&#32473; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span> &#25152;&#24341;&#29992;&#30340;&#20803;&#32032;&#12290;</div>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>value</td>
<td>-</td>
<td>&#36171;&#20540;&#32473;&#25152;&#26377;&#34987;&#24341;&#29992;&#20803;&#32032;&#30340;&#20540;</td>
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<td>val_arr</td>
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<td>&#29992;&#20197;&#36171;&#20540;&#30340; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-numeric-valarray.html"><span class="kw1473">std::<span class="me2">valarray</span></span></a></span></span></td>
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<td>sl_arr</td>
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<td>&#29992;&#20197;&#36171;&#20540;&#30340; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-numeric-valarray-indirect_array.html"><span class="kw1479">std::<span class="me2">indirect_array</span></span></a></span></span></td>
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<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">&#36820;&#22238;&#20540;</span></h3>
<div class="t-li1"><span class="t-li">1-2)</span> &#65288;&#26080;&#65289;</div>
<div class="t-li1"><span class="t-li">3)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span></div>
<h3><span class="mw-headline" id=".E5.BC.82.E5.B8.B8">&#24322;&#24120;</span></h3>
<p>&#21487;&#33021;&#25243;&#20986;&#23454;&#29616;&#23450;&#20041;&#30340;&#24322;&#24120;&#12290;</p>
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
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<pre class="de1"><span class="co2">#include &lt;iomanip&gt;</span>
<span class="co2">#include &lt;iostream&gt;</span>
<span class="co2">#include &lt;valarray&gt;</span>
<span class="co2">#include &lt;numeric&gt;</span>
<span class="kw4">void</span> print<span class="br0">(</span><span class="kw4">int</span> n, <a href="cpp-numeric-valarray.html"><span class="kw1473">std::<span class="me2">valarray</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span> <span class="kw4">const</span><span class="sy3">&amp;</span> v<span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> n <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;:&#39;</span><span class="sy4">;</span>
<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">int</span> e <span class="sy4">:</span> v<span class="br0">)</span> <a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <a href="cpp-io-manip-setw.html"><span class="kw1797">std::<span class="me2">setw</span></span></a><span class="br0">(</span><span class="nu0">3</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> e<span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-numeric-valarray.html"><span class="kw1473">std::<span class="me2">valarray</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span> v<span class="br0">(</span><span class="nu0">8</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-algorithm-iota.html"><span class="kw1655">std::<span class="me2">iota</span></span></a><span class="br0">(</span><a href="cpp-iterator-begin.html"><span class="kw676">std::<span class="me2">begin</span></span></a><span class="br0">(</span>v<span class="br0">)</span>, <a href="cpp-iterator-end.html"><span class="kw680">std::<span class="me2">end</span></span></a><span class="br0">(</span>v<span class="br0">)</span>, <span class="nu0">0</span><span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span><span class="nu0">1</span>, v<span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-numeric-valarray.html"><span class="kw1473">std::<span class="me2">valarray</span></span></a><span class="sy1">&lt;</span><a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a><span class="sy1">&gt;</span> idx<span class="br0">{</span><span class="nu0">1</span>, <span class="nu0">3</span>, <span class="nu0">5</span>, <span class="nu0">7</span><span class="br0">}</span><span class="sy4">;</span>
<span class="kw4">const</span> <a href="cpp-numeric-valarray-indirect_array.html"><span class="kw1479">std::<span class="me2">indirect_array</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span> ia <span class="sy1">=</span> v<span class="br0">[</span>idx<span class="br0">]</span><span class="sy4">;</span>
<span class="co1">// &#39;ia&#39; &#20195;&#34920; v[1], v[3], v[5], v[7]</span>
ia <span class="sy1">=</span> <span class="sy2">-</span><span class="nu0">1</span><span class="sy4">;</span> <span class="co1">// (1) &#65292;&#31561;&#25928;&#22320;&#65306;</span>
<span class="co1">// v[1] = v[3] = v[5] = v[7] = -1;</span>
print<span class="br0">(</span><span class="nu0">2</span>, v<span class="br0">)</span><span class="sy4">;</span>
ia <span class="sy1">=</span> <span class="coMULTI">/*std::valarray&lt;int&gt;*/</span><span class="br0">{</span><span class="sy2">-</span><span class="nu0">1</span>, <span class="sy2">-</span><span class="nu0">2</span>, <span class="sy2">-</span><span class="nu0">3</span>, <span class="sy2">-</span><span class="nu0">4</span><span class="br0">}</span><span class="sy4">;</span> <span class="co1">// (2) &#65292;</span>
<span class="co1">// &#31561;&#25928;&#22320;&#65306; v[1]=-1, v[3]=-2, v[5]=-3, v[7]=-4;</span>
print<span class="br0">(</span><span class="nu0">3</span>, v<span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-numeric-valarray.html"><span class="kw1473">std::<span class="me2">valarray</span></span></a><span class="sy1">&lt;</span><a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a><span class="sy1">&gt;</span> idx2<span class="br0">{</span><span class="nu0">0</span>, <span class="nu0">2</span>, <span class="nu0">4</span>, <span class="nu0">6</span><span class="br0">}</span><span class="sy4">;</span>
<span class="kw4">const</span> <a href="cpp-numeric-valarray-indirect_array.html"><span class="kw1479">std::<span class="me2">indirect_array</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span> ia2 <span class="sy1">=</span> v<span class="br0">[</span>idx2<span class="br0">]</span><span class="sy4">;</span>
<span class="co1">// &#39;ia2&#39; refers to v[0], v[2], v[4], v[6]</span>
ia <span class="sy1">=</span> ia2<span class="sy4">;</span> <span class="co1">// (3) &#65292;&#31561;&#25928;&#22320;&#65306;</span>
<span class="co1">// v[1]=v[0], v[3]=v[2], v[5]=v[4], v[7]=v[6];</span>
print<span class="br0">(</span><span class="nu0">4</span>, v<span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span></pre></div>
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<p>&#36755;&#20986;&#65306;</p>
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<pre class="de1">1: 0 1 2 3 4 5 6 7
2: 0 -1 2 -1 4 -1 6 -1
3: 0 -1 2 -2 4 -3 6 -4
4: 0 0 2 2 4 4 6 6</pre></div>
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