function _views_natural_sort_number_transform_match_callback in Views Natural Sort 7.2

Same name and namespace in other branches

1. 8.2 views_natural_sort.inc \_views_natural_sort_number_transform_match_callback()

Transforms a string representing numbers into a special format.

This special format can be sorted as if it was a number but in reality is being sorted alphanumerically.

Parameters

array $match: Array of matches passed from preg_replace_callback $match[0] is the entire matching string $match[1] if present, is the optional dash, preceded by optional whitespace $match[2] if present, is whole number portion of the decimal number $match[3] if present, is the fractional portion of the decimal number $match[4] if present, is the integer (when no fraction is matched).

Return value

string String representing a numerical value that will sort numerically in an alphanumeric search.

1 string reference to '_views_natural_sort_number_transform_match_callback'

views_natural_sort_numbers in ./views_natural_sort.inc

Transform numbers in a string into a natural sortable string.

File

./views_natural_sort.inc, line 129

The Views Natural Sort module include file.

Code

function _views_natural_sort_number_transform_match_callback(array $match) {

  // Remove commas and leading zeros from whole number.
  $whole = (string) (int) str_replace(',', '', isset($match[4]) && strlen($match[4]) > 0 ? $match[4] : $match[2]);

  // Remove traililng 0's from fraction, then add the decimal and one trailing
  // 0 and a space. The space serves as a way to always sort shorter decimal
  // numbers that match exactly as less than longer ones.
  // Ex: 3.05 and 3.05011.
  $fraction = trim('.' . $match[3], '0') . '0 ';
  $encode = sprintf('%02u', strlen($whole)) . $whole . $fraction;
  if (strlen($match[1])) {

    // Negative number. Make 10's complement. Put back any leading white space
    // and the dash requires intermediate to avoid double-replacing the same
    // digit. str_replace() seems to work by copying the source to the result,
    // then successively replacing within it, rather than replacing from the
    // source to the result.
    // In this case since rules are reverced we also have to use a character
    // that would be sorted higher than a space when a number is being compared
    // against a longer one that is identical in negative numbers. This is so
    // that longer numbers are always LESS than sorter numbers that have
    // identical beginnings. Ex: -3.05 and -3.05011.
    $digits = array(
      '0',
      '1',
      '2',
      '3',
      '4',
      '5',
      '6',
      '7',
      '8',
      '9',
      ' ',
    );
    $intermediate = array(
      'a',
      'b',
      'c',
      'd',
      'e',
      'f',
      'g',
      'h',
      'i',
      'j',
      'k',
    );
    $rev_digits = array(
      '9',
      '8',
      '7',
      '6',
      '5',
      '4',
      '3',
      '2',
      '1',
      '0',
      ':',
    );
    $encode = $match[1] . str_replace($intermediate, $rev_digits, str_replace($digits, $intermediate, $encode));
  }
  return $encode;
}