std::numeric_limits::max_exponent
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                    < cpp | types | numeric limits
                    
                                                            
                    | static const int max_exponent; | (until C++11) | |
| static constexpr int max_exponent; | (since C++11) | |
The value of std::numeric_limits<T>::max_exponent is the largest positive number n such that 2n-1
 is a representable finite value of the floating-point type T. 
[edit] Standard specializations
| T | value of std::numeric_limits<T>::max_exponent | 
| /* non-specialized */ | 0 | 
| bool | 0 | 
| char | 0 | 
| signed char | 0 | 
| unsigned char | 0 | 
| wchar_t | 0 | 
| char16_t | 0 | 
| char32_t | 0 | 
| short | 0 | 
| unsigned short | 0 | 
| int | 0 | 
| unsigned int | 0 | 
| long | 0 | 
| unsigned long | 0 | 
| long long | 0 | 
| unsigned long long | 0 | 
| float | FLT_MAX_EXP | 
| double | DBL_MAX_EXP | 
| long double | LDBL_MAX_EXP | 
[edit] Example
Demonstrates the relationships of max_exponent, max_exponent10, and max() for the type float:
Run this code
#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 << "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
| [static] | the smallest negative power of ten that is a valid normalized floating-point value (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] | the largest integer power of 10 that is a valid finite floating-point value (public static member constant) |