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numeric_limits::min_exponent | ||||
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staticconstint min_exponent; | (until C++11) | |
staticconstexprint min_exponent; | (since C++11) | |
The value ofstd::numeric_limits<T>::min_exponent is the lowest negative numbern such that\(\scriptsize r^{n-1}\)rn-1
, wherer isstd::numeric_limits<T>::radix, is a valid normalized value of the floating-point typeT.
T | value ofstd::numeric_limits<T>::min_exponent |
| /* non-specialized */ | 0 |
| bool | 0 |
| char | 0 |
| signedchar | 0 |
| unsignedchar | 0 |
| wchar_t | 0 |
| char8_t(since C++20) | 0 |
| char16_t(since C++11) | 0 |
| char32_t(since C++11) | 0 |
| short | 0 |
| unsignedshort | 0 |
| int | 0 |
| unsignedint | 0 |
| long | 0 |
| unsignedlong | 0 |
| longlong(since C++11) | 0 |
| unsignedlonglong(since C++11) | 0 |
| float | FLT_MIN_EXP |
| double | DBL_MIN_EXP |
| longdouble | LDBL_MIN_EXP |
Demonstrates the relationships ofmin_exponent,min_exponent10,min(), andradix for the typefloat:
#include <iostream>#include <limits> int main(){std::cout<<"min() = "<<std::numeric_limits<float>::min()<<'\n'<<"min_exponent10 = "<<std::numeric_limits<float>::min_exponent10<<'\n'<<std::hexfloat<<'\n'<<"min() = "<<std::numeric_limits<float>::min()<<'\n'<<"min_exponent = "<<std::numeric_limits<float>::min_exponent<<'\n';}
Output:
min() = 1.17549e-38min_exponent10 = -37 min() = 0x1p-126min_exponent = -125
[static] | the radix or integer base used by the representation of the given type (public static member constant)[edit] |
[static] | the smallest negative power of ten that is a valid normalized floating-point value (public static member constant)[edit] |
[static] | one more than the largest integer power of the radix that is a valid finite floating-point value (public static member constant)[edit] |
[static] | the largest integer power of 10 that is a valid finite floating-point value (public static member constant)[edit] |
