std::numeric_limits<T>::infinity
| static T infinity() throw(); | (until C++11) | |
| static constexpr T infinity() noexcept; | (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 | 
| char8_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 | 
Example
#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) | 
    © cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
    http://en.cppreference.com/w/cpp/types/numeric_limits/infinity