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 implementations, this is the number of digits stored for the mantissa plus one, because the mantissa has an implicit leading 1 and binary point).
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) |
| 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 |
|
[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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