std::numeric_limits<T>::infinity

 

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static T infinity()throw();		(until C++11)
staticconstexpr 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​
signedchar	​0​
unsignedchar	​0​
wchar_t	​0​
char8_t(since C++20)	​0​
char16_t(since C++11)	​0​
char32_t(since C++11)	​0​
short	​0​
unsignedshort	​0​
int	​0​
unsignedint	​0​
long	​0​
unsignedlong	​0​
longlong(since C++11)	​0​
unsignedlonglong(since C++11)	​0​
float	HUGE_VALF
double	HUGE_VAL
longdouble	HUGE_VALL

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

has_infinity [static]

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