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<div class="identifier-type">function</div><div class="header"><string></div><h1 itemprop="name"><span class="namespace" title="namespace std">std::</span><span class="token">stof</span><span class="cpp cpp11" title="C++11で追加">(C++11)</span></h1>
<div itemprop="articleBody"><p><div class="codehilite"><pre><span></span><code><span class="k">namespace</span><span class="w"> </span><span class="nn">std</span><span class="w"> </span><span class="p">{</span>
<span class="w"> </span><span class="kt">float</span><span class="w"> </span><span class="nf">stof</span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="n"><a href="basic_string.html">std::string</a></span><span class="o">&</span><span class="w"> </span><span class="n">str</span><span class="p">,</span><span class="w"> </span><span class="n"><a href="../cstddef/size_t.html">std::size_t</a></span><span class="o">*</span><span class="w"> </span><span class="n">idx</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="nb">nullptr</span><span class="p">);</span><span class="w"> </span><span class="c1">// (1)</span>
<span class="w"> </span><span class="kt">float</span><span class="w"> </span><span class="nf">stof</span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="n"><a href="basic_string.html">std::wstring</a></span><span class="o">&</span><span class="w"> </span><span class="n">str</span><span class="p">,</span><span class="w"> </span><span class="n"><a href="../cstddef/size_t.html">std::size_t</a></span><span class="o">*</span><span class="w"> </span><span class="n">idx</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="nb">nullptr</span><span class="p">);</span><span class="w"> </span><span class="c1">// (2)</span>
<span class="p">}</span>
</code></pre></div>
</p>
<h2>概要</h2>
<p>文字列<code>str</code>を数値として読み取って、<code>float</code>型の値に変換する。</p>
<h2>効果</h2>
<p>パラメータ<code>str</code>が<code>string</code>型であれば<code>std::strtof(str.c_str(), &end)</code>、<code>wstring</code>であれば<code>std::wcstof(str.c_str(), &end)</code>を呼び出して、その<a class="cpprefjp-defined-word" data-desc="関数呼び出し式の評価結果となるオブジェクト・値">戻り値</a>を返す。</p>
<p>パラメータ<code>idx</code>が非<code>nullptr</code>の場合、変換に使用されなかった要素のインデックス（<code>end - str.c_str()</code>）が格納される。</p>
<h2><a class="cpprefjp-defined-word" data-desc="関数呼び出し式の評価結果となるオブジェクト・値">戻り値</a></h2>
<p>変換して得られた数値が返される。</p>
<h2><a class="cpprefjp-defined-word" data-desc="問題が発生したときに、現在実行位置を過去に通過・記録した位置に戻し、文脈情報を添えて紐づけられた処理(例外ハンドラー)を呼び出す仕組み。またはその事態">例外</a></h2>
<ul>
<li>数値への変換が行われなかった場合、<code><a href="../stdexcept.html">std::invalid_argument</a></code>が送出される。</li>
<li>以下の条件に合致した場合、<code><a href="../stdexcept.html">std::out_of_range</a></code>が送出される。<ul>
<li><code>std::strtof()</code>関数が<code><a href="../cerrno/errno.html">errno</a></code>変数に<code><a href="../cerrno.html">ERANGE</a></code>を設定した場合</li>
<li>結果が範囲外の値になった場合 (C++14)</li>
</ul>
</li>
</ul>
<h2>備考</h2>
<h3>errnoの扱い</h3>
<ul>
<li>Visual C++ 11やGCC (libstdc++) 4.8.2では、この関数を呼び出すと<code>errno</code>の値が変更される。</li>
<li>Clang (libc++) 3.3では、この関数の呼び出し前後で<code>errno</code>の値は変化しない。</li>
</ul>
<h3>グローバルロケールの影響</h3>
<p>この関数は、<code><a href="../clocale/setlocale.html">setlocale()</a></code>関数により挙動が変化する。</p>
<ul>
<li><code>strtof()</code>関数での文字列先頭の空白を読み飛ばす処理に、<code><cctype></code>の<code>isspace()</code>関数が使用される。</li>
<li>小数点記号は<code>LC_NUMERIC</code>で指定されたものが使用される。</li>
</ul>
<h2>例</h2>
<p><div class="yata" id="6edfa6add2acc63c537e6ec497b97220820bb702"><div class="codehilite"><pre><span></span><code><span class="cp">#include <a href="../iostream.html"><iostream></a></span>
<span class="cp">#include <a href="../string.html"><string></a></span>
<span class="kt">int</span><span class="w"> </span><span class="nf">main</span><span class="p">()</span>
<span class="p">{</span>
<span class="w"> </span><span class="c1">// 10進法での変換</span>
<span class="w"> </span><span class="n"><a href="../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="s">"---- decimal point"</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="w"> </span><span class="kt">float</span><span class="w"> </span><span class="n">a</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n"><span style="color:#ff0000">std::stof</span></span><span class="p">(</span><span class="s">"1.5"</span><span class="p">);</span><span class="w"> </span><span class="c1">// <span style="color:#ff0000">std::stof</span>("1.5", nullptr);</span>
<span class="w"> </span><span class="n"><a href="../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n">a</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="w"> </span><span class="kt">float</span><span class="w"> </span><span class="n">aw</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n"><span style="color:#ff0000">std::stof</span></span><span class="p">(</span><span class="sa">L</span><span class="s">"1."</span><span class="p">);</span><span class="w"> </span><span class="c1">// <span style="color:#ff0000">std::stof</span>(L"1.", nullptr);</span>
<span class="w"> </span><span class="n"><a href="../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n">aw</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="w"> </span><span class="c1">// 指数表記の変換</span>
<span class="w"> </span><span class="n"><a href="../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="s">"---- base = 8"</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="w"> </span><span class="kt">float</span><span class="w"> </span><span class="n">b</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n"><span style="color:#ff0000">std::stof</span></span><span class="p">(</span><span class="s">"0.5e3"</span><span class="p">,</span><span class="w"> </span><span class="nb">nullptr</span><span class="p">);</span>
<span class="w"> </span><span class="n"><a href="../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n">b</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="w"> </span><span class="kt">float</span><span class="w"> </span><span class="n">bw</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n"><span style="color:#ff0000">std::stof</span></span><span class="p">(</span><span class="sa">L</span><span class="s">".25e3"</span><span class="p">,</span><span class="w"> </span><span class="nb">nullptr</span><span class="p">);</span>
<span class="w"> </span><span class="n"><a href="../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n">bw</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="w"> </span><span class="c1">// 16進法での変換</span>
<span class="w"> </span><span class="n"><a href="../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="s">"---- base = 16"</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="w"> </span><span class="kt">float</span><span class="w"> </span><span class="n">c</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n"><span style="color:#ff0000">std::stof</span></span><span class="p">(</span><span class="s">"0x1.2P3"</span><span class="p">,</span><span class="w"> </span><span class="nb">nullptr</span><span class="p">);</span>
<span class="w"> </span><span class="n"><a href="../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n">c</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="w"> </span><span class="kt">float</span><span class="w"> </span><span class="n">cw</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n"><span style="color:#ff0000">std::stof</span></span><span class="p">(</span><span class="sa">L</span><span class="s">"0x1.2P4"</span><span class="p">,</span><span class="w"> </span><span class="nb">nullptr</span><span class="p">);</span>
<span class="w"> </span><span class="n"><a href="../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n">cw</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="w"> </span><span class="c1">// 2番目の仮引数の使用例</span>
<span class="w"> </span><span class="n"><a href="../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="s">"---- use of idx parameter"</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="w"> </span><span class="n"><a href="basic_string.html">std::string</a></span><span class="w"> </span><span class="n">es</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="s">"30.75%"</span><span class="p">;</span>
<span class="w"> </span><span class="n"><a href="../cstddef/size_t.html">std::size_t</a></span><span class="w"> </span><span class="n">ei</span><span class="p">;</span>
<span class="w"> </span><span class="kt">float</span><span class="w"> </span><span class="n">e</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n"><span style="color:#ff0000">std::stof</span></span><span class="p">(</span><span class="n">es</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">ei</span><span class="p">);</span>
<span class="w"> </span><span class="n"><a href="../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n">e</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="sc">' '</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n">es</span><span class="p">[</span><span class="n">ei</span><span class="p">]</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="w"> </span><span class="n"><a href="basic_string.html">std::wstring</a></span><span class="w"> </span><span class="n">ews</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="sa">L</span><span class="s">"32%"</span><span class="p">;</span>
<span class="w"> </span><span class="n"><a href="../cstddef/size_t.html">std::size_t</a></span><span class="w"> </span><span class="n">ewi</span><span class="p">;</span>
<span class="w"> </span><span class="kt">float</span><span class="w"> </span><span class="n">ew</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n"><span style="color:#ff0000">std::stof</span></span><span class="p">(</span><span class="n">ews</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">ewi</span><span class="p">);</span>
<span class="w"> </span><span class="n"><a href="../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n">ew</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="sc">' '</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n">ewi</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="w"> </span><span class="c1">// 文字列先頭に空白がある場合</span>
<span class="w"> </span><span class="n"><a href="../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="s">"---- space character before number"</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="w"> </span><span class="n"><a href="../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><span style="color:#ff0000">std::stof</span></span><span class="p">(</span><span class="s">" -1"</span><span class="p">)</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="w"> </span><span class="n"><a href="../iostream/cout.html">std::cout</a></span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><span style="color:#ff0000">std::stof</span></span><span class="p">(</span><span class="sa">L</span><span class="s">" -.25"</span><span class="p">)</span><span class="w"> </span><span class="o"><<</span><span class="w"> </span><span class="n"><a href="../ostream/endl.html">std::endl</a></span><span class="p">;</span>
<span class="p">}</span>
</code></pre></div>
</div></p>
<h3>出力例</h3>
<p><pre><code>---- decimal point
1.5
1
---- base = 8
500
250
---- base = 16
9
18
---- use of idx parameter
30.75 %
32 2
---- space character before number
-1
-0.25
</code></pre></p>
<h2>実装例</h2>
<p><div class="codehilite"><pre><span></span><code><span class="kt">float</span><span class="w"> </span><span class="nf">stof</span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="n"><a href="basic_string.html">std::string</a></span><span class="o">&</span><span class="w"> </span><span class="n">str</span><span class="p">,</span><span class="w"> </span><span class="n"><a href="../cstddef/size_t.html">std::size_t</a></span><span class="o">*</span><span class="w"> </span><span class="n">idx</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="nb">nullptr</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="kt">char</span><span class="o">*</span><span class="w"> </span><span class="n">p</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n"><a href="basic_string/c_str.html">str.c_str()</a></span><span class="p">;</span>
<span class="w"> </span><span class="kt">char</span><span class="o">*</span><span class="w"> </span><span class="n">end</span><span class="p">;</span>
<span class="w"> </span><span class="n"><a href="../cerrno/errno.html">errno</a></span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
<span class="w"> </span><span class="kt">double</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">std</span><span class="o">::</span><span class="n">strtof</span><span class="p">(</span><span class="n">p</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">end</span><span class="p">);</span>
<span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">p</span><span class="w"> </span><span class="o">==</span><span class="w"> </span><span class="n">end</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
<span class="w"> </span><span class="k">throw</span><span class="w"> </span><span class="n"><a href="../stdexcept.html">std::invalid_argument</a></span><span class="p">(</span><span class="s">"stof"</span><span class="p">);</span>
<span class="w"> </span><span class="p">}</span>
<span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n"><a href="../cerrno/errno.html">errno</a></span><span class="w"> </span><span class="o">==</span><span class="w"> </span><span class="n"><a href="../cerrno.html">ERANGE</a></span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
<span class="w"> </span><span class="k">throw</span><span class="w"> </span><span class="n"><a href="../stdexcept.html">std::out_of_range</a></span><span class="p">(</span><span class="s">"stof"</span><span class="p">);</span>
<span class="w"> </span><span class="p">}</span>
<span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">idx</span><span class="w"> </span><span class="o">!=</span><span class="w"> </span><span class="nb">nullptr</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
<span class="w"> </span><span class="o">*</span><span class="n">idx</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="k">static_cast</span><span class="o"><</span><span class="n"><a href="../cstddef/size_t.html">std::size_t</a></span><span class="o">></span><span class="p">(</span><span class="n">end</span><span class="w"> </span><span class="o">-</span><span class="w"> </span><span class="n">p</span><span class="p">);</span>
<span class="w"> </span><span class="p">}</span>
<span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="k">static_cast</span><span class="o"><</span><span class="kt">float</span><span class="o">></span><span class="p">(</span><span class="n">x</span><span class="p">);</span>
<span class="p">}</span>
<span class="kt">float</span><span class="w"> </span><span class="nf">stof</span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="n"><a href="basic_string.html">std::wstring</a></span><span class="o">&</span><span class="w"> </span><span class="n">str</span><span class="p">,</span><span class="w"> </span><span class="n"><a href="../cstddef/size_t.html">std::size_t</a></span><span class="o">*</span><span class="w"> </span><span class="n">idx</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="nb">nullptr</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
<span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="kt">wchar_t</span><span class="o">*</span><span class="w"> </span><span class="n">p</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n"><a href="basic_string/c_str.html">str.c_str()</a></span><span class="p">;</span>
<span class="w"> </span><span class="kt">wchar_t</span><span class="o">*</span><span class="w"> </span><span class="n">end</span><span class="p">;</span>
<span class="w"> </span><span class="n"><a href="../cerrno/errno.html">errno</a></span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
<span class="w"> </span><span class="kt">double</span><span class="w"> </span><span class="n">x</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">std</span><span class="o">::</span><span class="n">wcstof</span><span class="p">(</span><span class="n">p</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">end</span><span class="p">);</span>
<span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">p</span><span class="w"> </span><span class="o">==</span><span class="w"> </span><span class="n">end</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
<span class="w"> </span><span class="k">throw</span><span class="w"> </span><span class="n"><a href="../stdexcept.html">std::invalid_argument</a></span><span class="p">(</span><span class="s">"stof"</span><span class="p">);</span>
<span class="w"> </span><span class="p">}</span>
<span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n"><a href="../cerrno/errno.html">errno</a></span><span class="w"> </span><span class="o">==</span><span class="w"> </span><span class="n"><a href="../cerrno.html">ERANGE</a></span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
<span class="w"> </span><span class="k">throw</span><span class="w"> </span><span class="n"><a href="../stdexcept.html">std::out_of_range</a></span><span class="p">(</span><span class="s">"stof"</span><span class="p">);</span>
<span class="w"> </span><span class="p">}</span>
<span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">idx</span><span class="w"> </span><span class="o">!=</span><span class="w"> </span><span class="nb">nullptr</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
<span class="w"> </span><span class="o">*</span><span class="n">idx</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="k">static_cast</span><span class="o"><</span><span class="n"><a href="../cstddef/size_t.html">std::size_t</a></span><span class="o">></span><span class="p">(</span><span class="n">end</span><span class="w"> </span><span class="o">-</span><span class="w"> </span><span class="n">p</span><span class="p">);</span>
<span class="w"> </span><span class="p">}</span>
<span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="k">static_cast</span><span class="o"><</span><span class="kt">float</span><span class="o">></span><span class="p">(</span><span class="n">x</span><span class="p">);</span>
<span class="p">}</span>
</code></pre></div>
</p>
<h2>バージョン</h2>
<h3>言語</h3>
<ul>
<li>C++11</li>
</ul>
<h3>処理系</h3>
<ul>
<li><a href="../../implementation.html#clang">Clang</a>: ?</li>
<li><a href="../../implementation.html#gcc">GCC</a>: 4.8.5 <span aria-label="検証済" role="img" title="検証済">✅</span></li>
<li><a href="../../implementation.html#icc">ICC</a>: ?</li>
<li><a href="../../implementation.html#visual_cpp">Visual C++</a>: 2010 <span aria-label="検証済" role="img" title="検証済">✅</span>, 2012 <span aria-label="検証済" role="img" title="検証済">✅</span>, 2013 <span aria-label="検証済" role="img" title="検証済">✅</span></li>
</ul>
<p>ただし、Visual C++ 10.0, 11.0は十六進法に対応していない（12.0は未確認）。</p>
<h2>関連リンク</h2>
<h3>C標準ライブラリに由来する関数</h3>
<ul>
<li><code>atof</code>: <code>stold</code>は<code>atof</code>を<code>std::string</code>および<code>std::wstring</code>に対応させ、<a class="cpprefjp-defined-word" data-desc="関数呼び出し式の評価結果となるオブジェクト・値">戻り値</a>の型を<code>float</code>に変更したものと見なせる。</li>
<li><code>strtof</code>, <code>wcstof</code>: <code>stof</code>は<code>strtof</code>および<code>wcstof</code>をそれぞれ<code>std::string</code>と<code>std::wstring</code>に対応させたものと見なせる。</li>
</ul>
<h3>ファミリー</h3>
<ul>
<li><code><a href="stoi.html">stoi</a></code>: <a class="cpprefjp-defined-word" data-desc="関数呼び出し式の評価結果となるオブジェクト・値">戻り値</a>の型が<code>int</code>となったもの。</li>
<li><code><a href="stol.html">stol</a></code>: <a class="cpprefjp-defined-word" data-desc="関数呼び出し式の評価結果となるオブジェクト・値">戻り値</a>の型が<code>long</code>となったもの。</li>
<li><code><a href="stoll.html">stoll</a></code>: <a class="cpprefjp-defined-word" data-desc="関数呼び出し式の評価結果となるオブジェクト・値">戻り値</a>の型が<code>long long</code>となったもの。</li>
<li><code><a href="stoul.html">stoul</a></code>: <a class="cpprefjp-defined-word" data-desc="関数呼び出し式の評価結果となるオブジェクト・値">戻り値</a>の型が<code>unsigned long</code>となったもの。</li>
<li><code><a href="stoull.html">stoull</a></code>: <a class="cpprefjp-defined-word" data-desc="関数呼び出し式の評価結果となるオブジェクト・値">戻り値</a>の型が<code>unsigned long long</code>となったもの。</li>
<li>(<code>stof</code>: この関数自身)</li>
<li><code><a href="stod.html">stod</a></code>: <a class="cpprefjp-defined-word" data-desc="関数呼び出し式の評価結果となるオブジェクト・値">戻り値</a>の型が<code>double</code>となったもの。</li>
<li><code><a href="stold.html">stold</a></code>: <a class="cpprefjp-defined-word" data-desc="関数呼び出し式の評価結果となるオブジェクト・値">戻り値</a>の型が<code>long double</code>となったもの。</li>
</ul>
<h3>ロケール依存しない高速な変換関数</h3>
<ul>
<li><code><a href="../charconv/from_chars.html">from_chars</a></code></li>
</ul>
<h2>参照</h2>
<ul>
<li><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2408.html" target="_blank">N2408 Simple Numeric Access Revision 2</a></li>
<li><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2009" target="_blank">LWG Issue 2009. Reporting out-of-bound values on numeric string conversions</a></li>
</ul></div>
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