std::numeric_limits::max_exponent

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numeric_limits::max_exponent
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static const int max_exponent;
 (until C++11)
static constexpr int max_exponent;
 (since C++11)

The value of std::numeric_limits<T>::max_exponent is the largest positive number n such that 2n-1
 is a representable finite value of the floating-point type T.

[edit] Standard specializations

T value of std::numeric_limits<T>::max_exponent
/* non-specialized */ ​0​
bool ​0​
char ​0​
signed char ​0​
unsigned char ​0​
wchar_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 FLT_MAX_EXP
double DBL_MAX_EXP
long double LDBL_MAX_EXP

[edit] 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
              << "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

[edit] See also

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