macro

isless

macro	isless(x,y)

function	bool isless (float x , float y); bool isless (double x , double y); bool isless (long double x, long double y);

Is less

Returns whether x is less than y.

If one or both arguments are NaN, the function returns false, but no FE_INVALID exception is raised (note that the expression x<y may raise such an exception in this case).

In C, this is implemented as a macro that returns an int value. The type of both x and y shall be float, double or long double.

In C++, it is implemented with function overloads for each floating-point type, each returning a bool value.

Parameters

x, y: Values to be compared.

Return value

The same as (x)<(y):
true (1) if x is less than y.
false (0) otherwise.

Example

/* isless example */
#include <stdio.h>      /* printf */
#include <math.h>       /* isless, log */

int main ()
{
  double result;
  result = log (10.0);

  if (isless(result,0.0))
    printf ("log(10.0) is negative");
  else
    printf ("log(10.0) is not negative");

  return 0;
}