// Returns the next higher or lower number
function NextRelatedNumber($number, $range){  
  $r = $number % $range;
  $f = $number - $r;
  $b = round($r / $range, 0);
  return ($b == 1) "\n";
// returns --> 40
// 0 20 40 60 80 100 ...
print 'NextHigherNumber: ';
print NextHigherNumber(41, 20) . "\n";
// returns --> 60
// 0 5 10 15 20 25 30 35 ...
print 'NextLowerNumber: ';
print NextLowerNumber(57, 5) . "\n";
// returns --> 55
// Example with Array
print 'NextNumberArray: ';
print NextNumberArray(45, array(3, 8, 19, 34, 56, 89)) . "\n";
// returns --> 34
// (45 is between 34 and 56 but 34 is the next)