std::numeric_limits<T>::digits
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 number of digits in the mantissa.
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 | CHAR_BIT |
char16_t | CHAR_BIT*sizeof(char16_t) |
char32_t | 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 | CHAR_BIT*sizeof(long long)-1 |
unsigned long long | 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) |
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