std::numeric_limits::infinity

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std::numeric_limits
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numeric_limits::infinity
Helper types
 
static T infinity();
 (until C++11)
static constexpr T infinity();
 (since C++11)

Returns the special value "positive infinity", as represented by the floating-point type T. Only meaningful if std::numeric_limits<T>::has_infinity == true. In IEEE 754, the most common binary representation of floating-point numbers, the positive infinity is the value with all bits of the exponent set and all bits of the fraction cleared.

Return value

T std::numeric_limits<T>::infinity()
/* non-specialized */ T();
bool false
char ​0​
signed char ​0​
unsigned char ​0​
wchar_t ​0​
char16_t ​0​
char32_t ​0​
short ​0​
unsigned short ​0​
int ​0​
unsigned int ​0​
long ​0​
unsigned long ​0​
long long ​0​
unsigned long long ​0​
float HUGE_VALF
double HUGE_VAL
long double HUGE_VALL

Exceptions

(none) (until C++11)
noexcept specification:  
noexcept
  
 (since C++11)

Example

Run this code
#include <iostream>
#include <limits>
int main()
{
    double max = std::numeric_limits<double>::max();
    double inf = std::numeric_limits<double>::infinity();
 
    if(inf > max)
        std::cout << inf << " is greater than " << max << '\n';
}

Output: 

inf is greater than 1.79769e+308


See also

[static]
 identifies floating-point types that can represent the special value "positive infinity"
(public static member constant)
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