std::numeric_limits<T>::max_exponent

 

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staticconstint max_exponent;		(until C++11)
staticconstexprint max_exponent;		(since C++11)

The value of std::numeric_limits<T>::max_exponent is the largest positive number n such that \(\scriptsize r^{n-1}\)rn-1
, where r is std::numeric_limits<T>::radix, is a representable finite value of the floating-point type T.

Standard specializations

T	value of std::numeric_limits<T>::max_exponent
/* non-specialized */	​0​
bool	​0​
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	FLT_MAX_EXP
double	DBL_MAX_EXP
longdouble	LDBL_MAX_EXP

Example

Demonstrates the relationships of max_exponent, max_exponent10, and max() for the type float:

Run this code

#include <iostream>#include <limits>   int main(){std::cout<<"max() = "<<std::numeric_limits<float>::max()<<'\n'<<"max_exponent10 = "<<std::numeric_limits<float>::max_exponent10<<'\n'<<std::hexfloat<<'\n'<<"max() = "<<std::numeric_limits<float>::max()<<'\n'<<"max_exponent = "<<std::numeric_limits<float>::max_exponent<<'\n';}

Output:

max() = 3.40282e+38 max_exponent10 = 38   max() = 0x1.fffffep+127 max_exponent = 128

See also

min_exponent10 [static]	the smallest negative power of ten that is a valid normalized floating-point value (public static member constant)
min_exponent [static]	one more than the smallest negative power of the radix that is a valid normalized floating-point value (public static member constant)
max_exponent10 [static]	the largest integer power of 10 that is a valid finite floating-point value (public static member constant)