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std::numeric_limits::digits

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Template:ddcl list begin <tr class="t-dcl-sep"><td></td><td></td><td></td></tr>

<tr class="t-dcl ">

<td >
static const int digits
</td>

<td class="t-dcl-nopad"> </td> <td > (until C++11) </td> </tr> <tr class="t-dcl-sep"><td></td><td></td><td></td></tr>

<tr class="t-dcl ">

<td >
static constexpr int digits
</td>

<td class="t-dcl-nopad"> </td> <td > (since C++11) </td> </tr> Template:ddcl list end

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. For floating-point types, this is the number of digits in the mantissa.

Standard specializations

T value of std::numeric_limits<T>::digits
/* 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
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) [edit]
one more than the smallest negative power of the radix that is a valid normalized floating-point value
(public static member constant) [edit]
one more than the largest integer power of the radix that is a valid finite floating-point value
(public static member constant) [edit]