decimal_to_fraction

/**
 * Turn decimals into fractions.
 */
function dec2frac($f) {
  $base = floor($f);
  if ($base) {
    $out = $base . ' ';
    $f = $f - $base;
  }
  if ($f != 0) {
    $d = 1;
    while (fmod($f, 1) != 0.0) {
      $f *= 2;
      $d *= 2;
    }
    $n = sprintf('%.0f', $f);
    $d = sprintf('%.0f', $d);
    $out .= $n . '/' . $d;
  }
  return $out;
}