Utilities library
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C numeric limits interface
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(C++11)(until C++20)
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(C++11)(until C++20)(C++17)
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.

[edit] 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
double HUGE_VAL
long double HUGE_VALL

[edit] 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';


inf is greater than 1.79769e+308

[edit] See also

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