std::numeric_limits::min_exponent(3)

NAME
std::numeric_limits::min_exponent - std::numeric_limits::min_exponent

Synopsis
   static const int min_exponent; (until C++11)
   static constexpr int min_exponent; (since C++11)
   The value of std::numeric_limits<T>::min_exponent is the lowest negative number n
   such that \(\scriptsize r^{n-1}\)rn-1
   , where r is std::numeric_limits<T>::radix, is a valid normalized value of the
   floating-point type T.

Standard specializations
   T value of std::numeric_limits<T>::min_exponent
   /* 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_MIN_EXP
   double DBL_MIN_EXP
   long double LDBL_MIN_EXP

Example
   Demonstrates the relationships of min_exponent, min_exponent10, min(), and radix for
   the type float: // Run this code
 #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-38
 min_exponent10 = -37
 min() = 0x1p-126
 min_exponent = -125

See also
   radix the radix or integer base used by the representation of the given
   [static] type
                  (public static member constant)
   min_exponent10 the smallest negative power of ten that is a valid normalized
   [static] floating-point value
                  (public static member constant)
   max_exponent one more than the largest integer power of the radix that is a valid
   [static] finite floating-point value
                  (public static member constant)
   max_exponent10 the largest integer power of 10 that is a valid finite floating-point
   [static] value
                  (public static member constant)