note 57895 added to ref.math

This is an efficient method of calculating the binomial coefficient C(n,k). This code was derived from Owant: Mastering Algorithms with Perl. <?php // calculate binomial coefficient function binomial_coeff($n, $k) { $j = $res = 1; if($k < 0 || $k > $n) return 0; if(($n - $k) < $k) $k = $n - $k; while($j <= $k) { $res *= $n--; $res /= $j++; } return $res; } ?> If you compiled php with --enable-bcmath, you can get full integer values of extremely large numbers by replacing: $res *= $n--; $res /= $j++; with: $res = bcmul($res, $n--); $res = bcdiv($res, $j++); ---- Manual Page -- http://www.php.net/manual/en/ref.math.php Edit -- http://master.php.net/manage/user-notes.php?action=edit+57895 Delete: added to the manual -- http://master.php.net/manage/user-notes.php?action=delete+57895&report=yes&reason=added+to+the+manual Delete: bad code -- http://master.php.net/manage/user-notes.php?action=delete+57895&report=yes&reason=bad+code Delete: spam -- http://master.php.net/manage/user-notes.php?action=delete+57895&report=yes&reason=spam Delete: useless -- http://master.php.net/manage/user-notes.php?action=delete+57895&report=yes&reason=useless Delete: non-english -- http://master.php.net/manage/user-notes.php?action=delete+57895&report=yes&reason=non-english Delete: already in docs -- http://master.php.net/manage/user-notes.php?action=delete+57895&report=yes&reason=already+in+docs Delete: other reasons -- http://master.php.net/manage/user-notes.php?action=delete+57895&report=yes Reject -- http://master.php.net/manage/user-notes.php?action=reject+57895&report=yes Search -- http://master.php.net/manage/user-notes.php