Standard library header <ratio> (C++11)
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This header is part of the compile-time rational arithmetic library.
Classes
Arithmetic
Comparison
(C++11)
ratio objects for less than or equal to at compile-time (class template) [edit]
(C++11)
ratio objects for greater than or equal to at compile-time (class template) [edit]
Type Aliases
quecto (C++26)
std::ratio <1, 1000000000000000000000000000000>, if std::intmax_t can represent the denominator
ronto (C++26)
std::ratio <1, 1000000000000000000000000000>, if std::intmax_t can represent the denominator
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>
ronna (C++26)
std::ratio <1000000000000000000000000000, 1>, if std::intmax_t can represent the numerator
quetta (C++26)
std::ratio <1000000000000000000000000000000, 1>, if std::intmax_t can represent the numerator
[edit] Synopsis
namespace std { // class template 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 arithmetic 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 comparison 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; // convenience SI typedefs 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; }