std::ratio_less

 

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Compile-time rational arithmetic
Compile-time integer sequences
integer_sequence (C++14)

 

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<bool, /* see below */>{};		(since C++11)

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 > constexprbool 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(){using x =std::ratio<69, 90>;using y =std::ratio<70, 90>;   ifconstexpr(std::ratio_less_v<x, y>)std::cout<< x::num<<'/'<< x::den<<" < "<< y::num<<'/'<< y::den<<'\n';}

Output:

23/30 < 7/9

See also

ratio_greater (C++11)

compares two ratio objects for greater than at compile-time (class template)