code: public static function format($size, $decimals = 2, $decPoint = '.', $thousandsSep = '', $unitSep = '')
      {
          $output = $unit = null;
          foreach (self::getBinarySizes() as $unit => $divider) {
              $output = $size / $divider;
              if ($output < 1000) {
                  break;
              }
          }
          if (null === $output) {
              throw new \UnexpectedValueException("Unable to parse value: '{$size}'");
          }
          $unit = $unit === 'o' ? 'o' : ucfirst($unit);
          $trimmed = rtrim(rtrim(number_format($output, $decimals, $decPoint, $thousandsSep), '0'), $decPoint);
          $formatted = $trimmed.$unitSep.$unit;
  
          return str_replace(' ', utf8_encode(chr(160)), $formatted);
      }
docs: Return a binary size in a human readable form.
  
  @param int    $size         number of octets
  @param int    $decimals
  @param string $decPoint
  @param string $thousandsSep
  @param string $unitSep
  
  @throws \UnexpectedValueException
  
  @return string