std::numeric_limits<T>::digits
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< cpp | types | numeric limits
static const int digits; |
(until C++11) | |
static constexpr int digits; |
(since C++11) | |
The value of
std::numeric_limits
<T>
::
digits
is the number of digits in base-radix that can be represented by the type T without change. For integer types, this is the number of bits not counting the sign bit and the padding bits (if any). For floating-point types, this is the digits of the mantissa (for IEC 559/IEEE 754
Standard specializations
T
|
value of
std::numeric_limits
<T>
::
digits
(assuming no padding bits |
| /* non-specialized */ | 0 |
| bool | 1 |
| char | CHAR_BIT - std::numeric_limits < char > :: is_signed |
| signed char | CHAR_BIT - 1 |
| unsigned char | CHAR_BIT |
| wchar_t |
CHAR_BIT
* sizeof(
wchar_t
)
- std::numeric_limits < wchar_t > :: is_signed |
| char8_t (since C++20) | CHAR_BIT |
| char16_t (since C++11) | CHAR_BIT * sizeof(char16_t) |
| char32_t (since C++11) | CHAR_BIT * sizeof(char32_t) |
| short | CHAR_BIT * sizeof( short ) - 1 |
| unsigned short | CHAR_BIT * sizeof(short) |
| int | CHAR_BIT * sizeof( int ) - 1 |
| unsigned int | CHAR_BIT * sizeof(int) |
| long | CHAR_BIT * sizeof( long ) - 1 |
| unsigned long | CHAR_BIT * sizeof(long) |
| long long (since C++11) | CHAR_BIT * sizeof( long long ) - 1 |
| unsigned long long (since C++11) | CHAR_BIT * sizeof( long long ) |
| float | FLT_MANT_DIG |
| double | DBL_MANT_DIG |
| long double | LDBL_MANT_DIG |
See also
|
[static]
|
the radix or integer base used by the representation of the given type (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]
|
one more than the largest integer power of the radix that is a valid finite floating-point value (public static member constant) |