Font-Awesome/scss/_functions.scss

// Functions
// --------------------------

// extract the number from a unit
@function unitless($number) {
  @return $number / ($number * 0 + 1);
}

// fudge a number to an accuracy of 0-6 decimal places
@function fudge($number, $places: 0) {
  $fraction: 10;
  $number: unitless($number);
  $return: null;

  @if $places == 0 {
    @return round($number);
  } @else {
    @if $places > 6 {
      $places: 6;
    }
    @for $i from 1 through $places {
      $fraction: $fraction * 10;
    }
    @return round($number * $fraction) / $fraction;
  }
}