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Embedded Template Library
Maths
ratio

ratio

Header: ratio.h
Since: TBC
Similar to: std::ratio

A template constant to encode ratios.

template <const size_t NUM, const size_t DEN = 1>
struct ratio
{
  static ETL_CONSTANT intmax_t num = NUM;
  static ETL_CONSTANT intmax_t den = DEN;
};

num : Numerator
den : Denominator

Predefined ratios

If INT_MAX > INT32_MAX

typedef ratio<1, 1000000000000000000LL * 1000000000000LL> quecto;
typedef ratio<1, 1000000000000000000LL * 1000000000LL>    ronto;
typedef ratio<1, 1000000000000000000000000LL> yocto;
typedef ratio<1, 1000000000000000000000>      zepto;
typedef ratio<1, 1000000000000000000>         atto;
typedef ratio<1, 1000000000000000>            femto;
typedef ratio<1, 1000000000000>               pico;

If INT_MAX >= INT32_MAX

typedef ratio<1, 1000000000>                  nano;
typedef ratio<1, 1000000>                     micro;

If INT_MAX >= INT16_MAX

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;

If INT_MAX >= INT32_MAX

typedef ratio<1000000, 1>                     mega;
typedef ratio<1000000000, 1>                  giga;

If INT_MAX > INT32_MAX

typedef ratio<1000000000000, 1>               tera;
typedef ratio<1000000000000000, 1>            peta;
typedef ratio<1000000000000000000, 1>         exa;
typedef ratio<1000000000000000000000, 1>      zetta;
typedef ratio<1000000000000000000000000LL, 1> yotta;
typedef ratio<1000000000000000000LL * 1000000000LL, 1>    ronna;
typedef ratio<1000000000000000000LL * 1000000000000LL, 1> quetta;
typedef ratio<355, 113> ratio_pi;

An approximation of PI to 6 digits.

typedef ratio<239, 169> ratio_root2;

An approximation of root 2.

typedef ratio<169, 239> ratio_1_over_root2;

An approximation of 1 over root 2.

typedef ratio<326, 120> ratio_e;

An approximation of e.

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