isnormal Macro

Returns true if its argument is normal.

Include

<math.h>

Prototype

int isnormal(floating-point x);

Argument

x
any floating-point number

Return Value

Returns true if x is normal, i.e. it is not NaN, infinite, subnormal, nor zero; it returns zero otherwise.

Example

See the notes at the beginning of this chapter or section for information on using printf() or scanf() (and other functions reading and writing the stdin or stdout streams) in the example code.

#include <math.h>
#include <stdio.h>

int main(void)
{
  double x, y, z;

  x = 5.0;
  y = 2.0;
  z = x / y;
  if(isnormal(z))
    printf("The division of %f by %f is normal\n", x, y);
}

Example Output

The division of 5.000000 by 2.000000 is normal