std::numeric_limits::min_exponent

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

The value of std::numeric_limits<T>::min_exponent is the lowest negative number n such that rn-1
, where r is std::numeric_limits<T>::radix is a valid normalized value of the floating-point type T.

[edit] Standard specializations

T value of std::numeric_limits<T>::min_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_MIN_EXP
double DBL_MIN_EXP
long double LDBL_MIN_EXP

[edit] Example

Demonstrates the relationships of min_exponent, min_exponent10, min, and radix for the type float:

Run this code
#include <iostream>
int main()
{
    std::cout << "min() = " << std::numeric_limits<float>::min() << '\n'
              << "min_exponent10 = " << std::numeric_limits<float>::min_exponent10 << '\n'
              << std::hexfloat
              << "min() = " << std::numeric_limits<float>::min() << '\n'
              << "min_exponent = " << std::numeric_limits<float>::min_exponent << '\n';
}

Output: 

min() = 1.17549e-38
min_exponent10 = -37
min() = 0x1p-126
min_exponent = -125

[edit] See also

[static]
 the radix or integer base used by the representation of the given type
(public static member constant)
[static]
 the smallest negative power of ten that is a valid normalized floating-point value
(public static member constant)
[static]
 one more than the largest integer power of the radix that is a valid finite 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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