std::ratio_less

 

C++

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Technical Specifications

 

Numerics library

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Compile time rational arithmetic

ratio (C++11)

Arithmetic

ratio_add (C++11)

ratio_subtract (C++11)

ratio_multiply (C++11)

ratio_divide (C++11)

Comparison

ratio_equal (C++11)

ratio_not_equal (C++11)

ratio_less (C++11)

ratio_less_equal (C++11)

ratio_greater (C++11)

ratio_greater_equal (C++11)

 

Defined in header <ratio>
template< class R1, class R2 > struct ratio_less : std::integral_constant;

If the ratio R1 is less than the ratio R2, provides the member constant value equal true. Otherwise, value is false.

Helper variable template

template< class R1, class R2 > constexpr bool ratio_less_v = ratio_less<R1, R2>::value;		(since C++17)

Inherited from std::integral_constant

Member constants

value [static]	true if R1::num * R2::den < R2::num * R1::den, or equivalent expression that avoids overflow , false otherwise (public static member constant)

Member functions

operator bool	converts the object to bool, returns value (public member function)
operator() (C++14)	returns value (public member function)

Member types

Type	Definition
value_type	bool
type	std::integral_constant<bool, value>

Example

Run this code

#include <iostream>
#include <ratio>
 
int main()
{
    if (std::ratio_less<std::ratio<23,37>, std::ratio<57,90>>::value) {
        std::cout << "23/37 < 57/90\n";
    }
}

Output:

23/37 < 57/90

See also

std::experimental::ratio_less_v (library fundamentals TS)	variable template alias of std::ratio_less::value (variable template)