std::numeric_limits<T>::min_exponent
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 \(\scriptsize r^{n-1}\)rn-1
, where r
is std::numeric_limits<T>::radix
, is a valid normalized value of the floating-point type T
.
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 |
char8_t (C++20) |
0 |
char16_t (C++11) |
0 |
char32_t (C++11) |
0 |
short |
0 |
unsigned short |
0 |
int |
0 |
unsigned int |
0 |
long |
0 |
unsigned long |
0 |
long long (C++11) |
0 |
unsigned long long (C++11) |
0 |
float |
FLT_MIN_EXP |
double |
DBL_MIN_EXP |
long double |
LDBL_MIN_EXP |
Example
Demonstrates the relationships of min_exponent
, min_exponent10
, min
, and radix
for the type float
:
#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
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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