Namespaces
Variants
Views
Actions

std::numeric_limits<T>::max_exponent10

From cppreference.com
 
 
Utilities library
Language support
Type support (basic types, RTTI)
Library feature-test macros (C++20)
Dynamic memory management
Program utilities
Coroutine support (C++20)
Variadic functions
Debugging support
(C++26)
Three-way comparison
(C++20)
(C++20)(C++20)(C++20)
(C++20)(C++20)(C++20)
General utilities
Date and time
Function objects
Formatting library (C++20)
(C++11)
Relational operators (deprecated in C++20)
Integer comparison functions
(C++20)(C++20)(C++20)   
(C++20)
Swap and type operations
(C++14)
(C++11)
(C++11)
(C++11)
(C++17)
Common vocabulary types
(C++11)
(C++17)
(C++17)
(C++17)
(C++11)
(C++17)
(C++23)
Elementary string conversions
(C++17)
(C++17)

 
 
 
static const int max_exponent10;
(until C++11)
static constexpr int max_exponent10;
(since C++11)

The value of std::numeric_limits<T>::max_exponent10 is the largest positive number n such that 10n
is a representable finite value of the floating-point type T.

[edit] Standard specializations

T value of std::numeric_limits<T>::max_exponent10
/* non-specialized */ 0
bool 0
char 0
signed char 0
unsigned char 0
wchar_t 0
char8_t (since C++20) 0
char16_t (since C++11) 0
char32_t (since C++11) 0
short 0
unsigned short 0
int 0
unsigned int 0
long 0
unsigned long 0
long long (since C++11) 0
unsigned long long (since C++11) 0
float FLT_MAX_10_EXP
double DBL_MAX_10_EXP
long double LDBL_MAX_10_EXP

[edit] Example

Demonstrates the relationships of max_exponent, max_exponent10, and max() for the type float:

#include <iostream>
#include <limits>
 
int main()
{
    std::cout << "max() = " << std::numeric_limits<float>::max() << '\n'
              << "max_exponent10 = " << std::numeric_limits<float>::max_exponent10 << '\n'
              << std::hexfloat << '\n'
              << "max() = " << std::numeric_limits<float>::max() << '\n'
              << "max_exponent = " << std::numeric_limits<float>::max_exponent << '\n';
}

Output:

max() = 3.40282e+38
max_exponent10 = 38
 
max() = 0x1.fffffep+127
max_exponent = 128

[edit] See also

one more than the largest integer power of the radix that is a valid finite floating-point value
(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]
the smallest negative power of ten that is a valid normalized floating-point value
(public static member constant) [edit]