std::numeric_limits<T>:: max_exponent10
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(C++11)
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numeric_limits::max_exponent10
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(C++11)
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static
const
int
max_exponent10
;
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(until C++11) | |
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static
constexpr
int
max_exponent10
;
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(since C++11) | |
The value of
std::
numeric_limits
<
T
>
::
max_exponent10
is the largest positive number
n
such that
\(\scriptsize 10^n\)
10
n
is a representable finite value of the floating-point type
T
.
Standard specializations
T
|
value of std:: numeric_limits < T > :: max_exponent10 |
| /* non-specialized */ | 0 |
| bool | 0 |
| char | 0 |
| signed char | 0 |
| unsigned char | 0 |
| wchar_t | 0 |
| char8_t (since C++20) | 0 |
| char16_t (since C++11) | 0 |
| char32_t (since C++11) | 0 |
| short | 0 |
| unsigned short | 0 |
| int | 0 |
| unsigned int | 0 |
| long | 0 |
| unsigned long | 0 |
| long long (since C++11) | 0 |
| unsigned long long (since C++11) | 0 |
| float | FLT_MAX_10_EXP |
| double | DBL_MAX_10_EXP |
| long double | LDBL_MAX_10_EXP |
Example
Demonstrates the relationships of
max_exponent
,
max_exponent10
, and
max()
for the type
float
:
#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
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[static]
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one more than the largest integer power of the radix that is a valid finite floating-point value
(public static member constant) |
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[static]
|
one more than the smallest negative power of the radix that is a valid normalized floating-point value
(public static member constant) |
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[static]
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the smallest negative power of ten that is a valid normalized floating-point value
(public static member constant) |