std::chrono::floor(std::chrono::duration)

 

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std::chrono::duration

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Defined in header <chrono>
template <class ToDuration, class Rep, class Period> constexpr ToDuration floor(const duration<Rep, Period>& d);		(since C++17)

Returns the greatest duration t representable in ToDuration that is less or equal to d.

The function does not participate in the overload resolution unless ToDuration is an instance of std::chrono::duration.

Parameters

d

-

duration to convert

Return value

d rounded down to a duration of type ToDuration.

Possible implementation

template <class T> struct is_duration : std::false_type {}; template <class Rep, class Period> struct is_duration< std::chrono::duration<Rep, Period>> : std::true_type {};   template <class To, class Rep, class Period, class = std::enable_if_t<is_duration<To>{}>> constexpr To floor(const duration<Rep, Period>& d) { To t = std::chrono::duration_cast<To>(d); if (t > d) return t - To{1}; return t; }

See also

duration_cast	converts a duration to another, with a different tick interval (function template)
ceil(std::chrono::duration) (C++17)	converts a duration to another, rounding up (function template)
round(std::chrono::duration) (C++17)	converts a duration to another, rounding to nearest, ties to even (function template)
floor(std::chrono::time_point) (C++17)	converts a time_point to another, rounding down (function template)
floorfloorffloorl (C++11)(C++11)	nearest integer not greater than the given value (function)