/* epsilon-equal.c: define a error resist compare. */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif /* Def: HAVE_CONFIG_H */

#include "types.h"
#include "epsilon-equal.h"
#include <math.h>

/* Numerical errors sometimes make a floating point number just slightly
   larger or smaller than its true value.  When it matters, we need to
   compare with some tolerance, REAL_EPSILON, defined in kbase.h.  */

at_bool
epsilon_equal (at_real v1, at_real v2)
{
  if (v1 == v2		       /* Usually they'll be exactly equal, anyway.  */
    || fabs (v1 - v2) <= REAL_EPSILON)
    return true;
  else
    return false;
}