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 typeT. Only meaningful ifstd::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
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

[edit]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';}