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Basic types | |||||||||||||||||||||
Fixed width integer types(C++11) | |||||||||||||||||||||
Fixed width floating-point types(C++23) | |||||||||||||||||||||
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Numeric limits | |||||||||||||||||||||
C numeric limits interface | |||||||||||||||||||||
Runtime type information | |||||||||||||||||||||
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Static constants | ||||
(C++11) | ||||
Static member functions | ||||
numeric_limits::lowest (C++11) | ||||
Helper types | ||||
staticconstexpr T lowest()noexcept; | (since C++11) | |
Returns the lowest finite value representable by the numeric typeT
, that is, a finite valuex such that there is no other finite valuey wherey< x. This is different fromstd::numeric_limits<T>::min() for floating-point types. Only meaningful for bounded types.
Contents |
T | std::numeric_limits<T>::lowest() |
/* non-specialized */ | T() |
bool | false |
char | CHAR_MIN |
signedchar | SCHAR_MIN |
unsignedchar | 0 |
wchar_t | WCHAR_MIN |
char8_t(since C++20) | 0 |
char16_t | 0 |
char32_t | 0 |
short | SHRT_MIN |
unsignedshort | 0 |
int | INT_MIN |
unsignedint | 0 |
long | LONG_MIN |
unsignedlong | 0 |
longlong | LLONG_MIN |
unsignedlonglong | 0 |
float | -FLT_MAX |
double | -DBL_MAX |
longdouble | -LDBL_MAX |
For every standard C++ floating-point typeT
std::numeric_limits<T>::lowest()==-std::numeric_limits<T>::max(), but this does not necessarily have to be the case for any third-party specialization.
Demonstratesmin(),max(), andlowest()
for floating-point types:
#include <iostream>#include <limits>#include <string_view> template<typename T>void print_twice(std::string_view type, T value){std::cout<<'\t'<< type<<": "<<std::defaultfloat<< value<<" or "<<std::hexfloat<< value<<'\n';} int main(){// min()std::cout<<"std::numeric_limits<T>::min():\n"; print_twice("float",std::numeric_limits<float>::min()); print_twice("double",std::numeric_limits<double>::min()); print_twice("long double",std::numeric_limits<longdouble>::min()); // lowest()std::cout<<"std::numeric_limits<T>::lowest():\n"; print_twice("float",std::numeric_limits<float>::lowest()); print_twice("double",std::numeric_limits<double>::lowest()); print_twice("long double",std::numeric_limits<longdouble>::lowest()); // max()std::cout<<"std::numeric_limits<T>::max():\n"; print_twice("float",std::numeric_limits<float>::max()); print_twice("double",std::numeric_limits<double>::max()); print_twice("long double",std::numeric_limits<longdouble>::max());}
Output:
std::numeric_limits<T>::min():float: 1.17549e-38 or 0x1p-126double: 2.22507e-308 or 0x1p-1022long double: 3.3621e-4932 or 0x8p-16385std::numeric_limits<T>::lowest():float: -3.40282e+38 or -0x1.fffffep+127double: -1.79769e+308 or -0x1.fffffffffffffp+1023long double: -1.18973e+4932 or -0xf.fffffffffffffffp+16380std::numeric_limits<T>::max():float: 3.40282e+38 or 0x1.fffffep+127double: 1.79769e+308 or 0x1.fffffffffffffp+1023long double: 1.18973e+4932 or 0xf.fffffffffffffffp+16380
[static] | returns the smallest finite value of the given non-floating-point type, or the smallest positive normal value of the given floating-point type (public static member function)[edit] |
[static] | returns the smallest positive subnormal value of the given floating-point type (public static member function)[edit] |
[static] | returns the largest finite value of the given type (public static member function)[edit] |