std::isnormal (3) Linux Manual Page

std::isnormal – std::isnormal

Synopsis

Defined in header <cmath>
bool isnormal( float arg ); (1) (since C++11)
bool isnormal( double arg ); (2) (since C++11)
bool isnormal( long double arg ); (3) (since C++11)
bool isnormal( IntegralType arg ); (4) (since C++11)
1-3) Determines if the given floating point number arg is normal, i.e. is neither zero, subnormal, infinite, nor NaN.
4) A set of overloads or a function template accepting the arg argument of any integral_type. Equivalent to (2) (the argument is cast to double).

Parameters

arg – floating point value

Return value

true if arg is normal, false otherwise

Example

// Run this code

#include <iostream>

#include <cmath>

#include <cfloat>
int main()

{
    std::cout << std::boolalpha
              << "isnormal(NaN) = " << std::isnormal(NAN) << '\n'
              << "isnormal(Inf) = " << std::isnormal(INFINITY) << '\n'
              << "isnormal(0.0) = " << std::isnormal(0.0) << '\n'
              << "isnormal(DBL_MIN/2.0) = " << std::isnormal(DBL_MIN / 2.0) << '\n'
              << "isnormal(1.0) = " << std::isnormal(1.0) << '\n';
}

Output:

  isnormal(NaN) = false
  isnormal(Inf) = false
  isnormal(0.0) = false
  isnormal(DBL_MIN/2.0) = false
  isnormal(1.0) = true

See also

fpclassify categorizes the given floating point value
           (function)
(C++11)
isfinite checks if the given number has finite value
           (function)
(C++11)
isinf checks if the given number is infinite
           (function)
(C++11)
isnan checks if the given number is NaN
           (function)
(C++11)