W3cubDocs

/C++

std::isnormal

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

#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

(C++11)
 categorizes the given floating point value
(function)
(C++11)
 checks if the given number has finite value
(function)
(C++11)
 checks if the given number is infinite
(function)
(C++11)
 checks if the given number is NaN
(function)
C documentation for isnormal

© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
http://en.cppreference.com/w/cpp/numeric/math/isnormal