标准库标头 <ratio>
来自cppreference.com
此头文件是编译时有理数算术库的一部分。
类 | |
(C++11) |
表示精确的有理分数 (类模板) |
算术 | |
(C++11) |
在编译时相加两个 ratio 对象 (别名模板) |
(C++11) |
在编译时相减两个 ratio 对象 (别名模板) |
(C++11) |
在编译时相乘两个 ratio 对象 (别名模板) |
(C++11) |
在编译时相除两个 ratio 对象 (别名模板) |
比较 | |
(C++11) |
在编译时比较两个 ratio 对象的相等性 (类模板) |
(C++11) |
在编译时比较两个 ratio 对象的不相等性 (类模板) |
(C++11) |
在编译时比较两个 ratio 对象的小于关系 (类模板) |
(C++11) |
在编译时比较两个 ratio 对象的小于或等于关系 (类模板) |
(C++11) |
在编译时比较两个 ratio 对象的大于关系 (类模板) |
(C++11) |
在编译时比较两个 ratio 对象的大于或等于关系 (类模板) |
类型别名 | |
quecto (C++26)
|
std::ratio<1, 1000000000000000000000000000000>，若 std::intmax_t 能表示分母
|
ronto (C++26)
|
std::ratio<1, 1000000000000000000000000000>，若 std::intmax_t 能表示分母
|
yocto
|
std::ratio<1, 1000000000000000000000000>，若 std::intmax_t 能表示分母
|
zepto
|
std::ratio<1, 1000000000000000000000>，若 std::intmax_t 能表示分母
|
atto
|
std::ratio<1, 1000000000000000000>
|
femto
|
std::ratio<1, 1000000000000000>
|
pico
|
std::ratio<1, 1000000000000>
|
nano
|
std::ratio<1, 1000000000>
|
micro
|
std::ratio<1, 1000000>
|
milli
|
std::ratio<1, 1000>
|
centi
|
std::ratio<1, 100>
|
deci
|
std::ratio<1, 10>
|
deca
|
std::ratio<10, 1>
|
hecto
|
std::ratio<100, 1>
|
kilo
|
std::ratio<1000, 1>
|
mega
|
std::ratio<1000000, 1>
|
giga
|
std::ratio<1000000000, 1>
|
tera
|
std::ratio<1000000000000, 1>
|
peta
|
std::ratio<1000000000000000, 1>
|
exa
|
std::ratio<1000000000000000000, 1>
|
zetta
|
std::ratio<1000000000000000000000, 1>，若 std::intmax_t 能表示分子
|
yotta
|
std::ratio<1000000000000000000000000, 1>，若 std::intmax_t 能表示分子
|
ronna (C++26)
|
std::ratio<1000000000000000000000000000, 1>，若 std::intmax_t 能表示分子
|
quetta (C++26)
|
std::ratio<1000000000000000000000000000000, 1>，若 std::intmax_t 能表示分子
|
概要
namespace std {
// 类模板 ratio
template <intmax_t N, intmax_t D = 1>
class ratio {
public:
typedef ratio<num, den> type;
static constexpr intmax_t num;
static constexpr intmax_t den;
};
// ratio 算术
template <class R1, class R2> using ratio_add = /*ratio*/;
template <class R1, class R2> using ratio_subtract = /*ratio*/;
template <class R1, class R2> using ratio_multiply = /*ratio*/;
template <class R1, class R2> using ratio_divide = /*ratio*/;
// ratio 比较
template <class R1, class R2> struct ratio_equal;
template <class R1, class R2> struct ratio_not_equal;
template <class R1, class R2> struct ratio_less;
template <class R1, class R2> struct ratio_less_equal;
template <class R1, class R2> struct ratio_greater;
template <class R1, class R2> struct ratio_greater_equal;
// 便利 SI typedef
typedef ratio<1, 1000000000000000000000000000000> quecto;
typedef ratio<1, 1000000000000000000000000000> ronto;
typedef ratio<1, 1000000000000000000000000> yocto;
typedef ratio<1, 1000000000000000000000> zepto;
typedef ratio<1, 1000000000000000000> atto;
typedef ratio<1, 1000000000000000> femto;
typedef ratio<1, 1000000000000> pico;
typedef ratio<1, 1000000000> nano;
typedef ratio<1, 1000000> micro;
typedef ratio<1, 1000> milli;
typedef ratio<1, 100> centi;
typedef ratio<1, 10> deci;
typedef ratio< 10, 1> deca;
typedef ratio< 100, 1> hecto;
typedef ratio< 1000, 1> kilo;
typedef ratio< 1000000, 1> mega;
typedef ratio< 1000000000, 1> giga;
typedef ratio< 1000000000000, 1> tera;
typedef ratio< 1000000000000000, 1> peta;
typedef ratio< 1000000000000000000, 1> exa;
typedef ratio< 1000000000000000000000, 1> zetta;
typedef ratio< 1000000000000000000000000, 1> yotta;
typedef ratio< 1000000000000000000000000000, 1> ronna;
typedef ratio<1000000000000000000000000000000, 1> quetta;
}