std::stof, std::stod, std::stold

 

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メンバ関数 basic_string::basic_string basic_string::operator= basic_string::assign basic_string::get_allocator 要素アクセス basic_string::at basic_string::operator[] basic_string::front (C++11) basic_string::back (C++11) basic_string::data basic_string::c_str basic_string::operator basic_string_view (C++17) イテレータ basic_string::beginbasic_string::cbegin (C++11) basic_string::endbasic_string::cend (C++11) basic_string::rbeginbasic_string::crbegin (C++11) basic_string::rendbasic_string::crend (C++11) 容量 basic_string::empty basic_string::sizebasic_string::length basic_string::max_size basic_string::reserve basic_string::capacity basic_string::shrink_to_fit (C++11)

操作 basic_string::clear basic_string::insert basic_string::erase basic_string::push_back basic_string::pop_back (C++11) basic_string::append basic_string::operator+= basic_string::compare basic_string::starts_with (C++20) basic_string::ends_with (C++20) basic_string::replace basic_string::substr basic_string::copy basic_string::resize basic_string::swap 検索 basic_string::find basic_string::rfind basic_string::find_first_of basic_string::find_first_not_of basic_string::find_last_of basic_string::find_last_not_of 定数 basic_string::npos

非メンバ関数 operator+ operator==operator!=operator<operator>operator<=operator>= swap(std::basic_string) operator<<operator>> getline stoistolstoll (C++11)(C++11)(C++11) stoulstoull (C++11)(C++11) stofstodstold (C++11)(C++11)(C++11) to_string (C++11) to_wstring (C++11) operator""s (C++14) ヘルパークラス hash<std::string>hash<std::wstring>hash<std::u32string>hash<std::u16string> (C++11)(C++11)(C++11)(C++11) hash<std::pmr::string>hash<std::pmr::wstring>hash<std::pmr::u32string>hash<std::pmr::u16string> (C++20)(C++20)(C++20)(C++20) 推定ガイド(C++17)

 

ヘッダ <string> で定義
float       stof( const std::string& str, size_t *pos = 0 );	(1)	(C++11およびそれ以降)
double      stod( const std::string& str, size_t *pos = 0 );	(2)	(C++11およびそれ以降)
long double stold( const std::string& str, size_t *pos = 0 );	(3)	(C++11およびそれ以降)

文字列strの浮動小数点値を解釈.

Original:

Interprets a floating point value in a string str.

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最初の非空白文字が検出されるまで、この関数は（std::isspace()によって決定されるように）任意の空白文字を破棄します。それは有効な浮動小数点表現を形成するために、できるだけ多くの文字を取り、浮動小数点値に変換します。有効な浮動小数点値は、次のいずれかを指定できます

Original:

Function discards any whitespace characters (as determined by std::isspace()) until first non-whitespace character is found. Then it takes as many characters as possible to form a valid floating point representation and converts them to floating point value. The valid floating point value can be one of the following:

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• 進浮動小数点式。それは次の部分から構成されます

  Original:

  decimal floating point expression. It consists of the following parts:

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• (オプション)プラス記号またはマイナス記号

  Original:

  (オプション) plus or minus sign

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• オプションで小数点文字（定義仮）を含む小数桁数の空ではないシーケンス

  Original:

  nonempty sequence of decimal digits optionally containing a decimal point character (defines significand)

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• (オプション)eまたはEマイナスオプションまたはプラス記号と小数点以下桁数の空でないシーケンス（定義指数）と続いた

  Original:

  (オプション) e or E followed with optional minus or plus sign and nonempty sequence of decimal digits (defines exponent)

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• 進浮動小数点式。それは次の部分から構成されます

  Original:

  binary floating point expression. It consists of the following parts:

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• (オプション)プラス記号またはマイナス記号

  Original:

  (オプション) plus or minus sign

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• 0x or 0X
• オプションで小数点文字（定義仮）を含む進数字の空ではないシーケンス

  Original:

  nonempty sequence of hexadecimal digits optionally containing a decimal point character (defines significand)

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• (オプション)pまたはPマイナスオプションまたはプラス記号と16進数の空でないシーケンス（定義指数）と続いた

  Original:

  (オプション) p or P followed with optional minus or plus sign and nonempty sequence of hexadecimal digits (defines exponent)

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• 無限式。それは次の部分から構成されます

  Original:

  infinity expression. It consists of the following parts:

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• (オプション)プラス記号またはマイナス記号

  Original:

  (オプション) plus or minus sign

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• INFまたはINFINITY大文字小文字の区別を無視して

  Original:

  INF or INFINITY ignoring case

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• 非数値式。それは次の部分から構成されます

  Original:

  not-a-number expression. It consists of the following parts:

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• (オプション)プラス記号またはマイナス記号

  Original:

  (オプション) plus or minus sign

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• NANまたはNAN(' char_sequence)NAN部分の大文字小文字の区別を無視。 ' char_sequence英数字のみを含めることができます。結果はクワイエットNaN浮動小数点値です.

  Original:

  NAN or NAN(char_sequence) ignoring case of the NAN part. char_sequence can only contain alphanumeric characters. The result is a quiet NaN floating point value.

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ない最初の文字のインデックスにposに格納されています。NULLがposとして渡された場合、それは無視される.

Original:

The index of the first unconverted character is stored in pos. If NULL is passed as pos, it is ignored.

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パラメータ

str	-	変換する文字列 Original: the string to convert The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
pos	-	ない最初の文字のインデックスを格納する整数のアドレス Original: address of integer to store the index of the first unconverted character The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

値を返します

文字列は、指定された浮動小数点型に変換.

Original:

The string converted to the specified floating point type.

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例外

std::invalid_argument変換が行われなかった場合

Original:

std::invalid_argument if no conversion could be performed

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std::out_of_range変換された値が結果の型の範囲外に落ちるならば.

Original:

std::out_of_range if the converted value would fall out of the range of the result type.

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参照

stoistolstoll (C++11)(C++11)(C++11)	文字列を符号付き整数に変換します (関数)
stoulstoull (C++11)(C++11)	文字列を符号なし整数に変換します (関数)