public static function getDirectionByCoordinates($a, $b)
    {
        if ($a < $b) {
            return self::DIRECTION_POSITIVE;
        } elseif ($a > $b) {
            return self::DIRECTION_NEGATIVE;
        } else {
            return self::DIRECTION_NULL;
        }
    }
public static function getDirectionByCoordinates($a, $b)
    {
        if ($a < $b) {
            return self::DIRECTION_POSITIVE;
        } elseif ($a > $b) {
            return self::DIRECTION_NEGATIVE;
        } else {
            return self::DIRECTION_NULL;
        }
    }
public static function getDirectionByCoordinates ( $ a , $ b ) { if ( $ a < $ b ) { return self :: DIRECTION_POSITIVE ; } elseif ( $ a > $ b ) { return self :: DIRECTION_NEGATIVE ; } else { return self :: DIRECTION_NULL ; } }
Get the directions between two points

This will return:

-    `1` if [a->b] evolves in positive direction
-    `-1` if [a->b] evolves in negative direction
-    `0` if [a->b] does not evolve (same point)

@param   int  $a
@param   int  $b
@return  int
Get the directions between two points