note 56146 added to function.rand

I am sorry to tell you this, mark at mmpro dot de, but the function you mentioned looks awfully and unnecessarily slow to me: At each iteration, you have to check if the generated number is not already in the list, so you end up with a complexity of O(n²)... at best! (In the worst case, the algorithm might just run forever!!!) ---- Here is a better (and safer!) way to generate a random array of different numbers: - First generate an array, each element filled with a different value (like: 1,2,3,4,5,...,n) - Then shuffle your array. In other words, swap each element in your array with another randomly-chosen element in the array. Now the algorithm has a complexity of O(n), instead of the original O(n²). ---- The generation of the array of values is left at the discretion of the programmer (it is down to his/her needs to determine how the values should be reparted). The shuffling of the array should go like this (WARNING: CODE NOT TESTED !!!): $length = count($array) ; for($i=0; $i<$length; $i++) { // Choosing an element at random $randpos = rand(0, $length-1) ; // Swapping elements $temp = $array[$randpos] ; $array[$randpos] = $array[$i] ; $array[$i] = $temp ; } return $array ; ---- Manual Page -- http://www.php.net/manual/en/function.rand.php Edit -- http://master.php.net/manage/user-notes.php?action=edit+56146 Delete: added to the manual -- http://master.php.net/manage/user-notes.php?action=delete+56146&report=yes&reason=added+to+the+manual Delete: bad code -- http://master.php.net/manage/user-notes.php?action=delete+56146&report=yes&reason=bad+code Delete: spam -- http://master.php.net/manage/user-notes.php?action=delete+56146&report=yes&reason=spam Delete: useless -- http://master.php.net/manage/user-notes.php?action=delete+56146&report=yes&reason=useless Delete: non-english -- http://master.php.net/manage/user-notes.php?action=delete+56146&report=yes&reason=non-english Delete: other reasons -- http://master.php.net/manage/user-notes.php?action=delete+56146&report=yes Reject -- http://master.php.net/manage/user-notes.php?action=reject+56146&report=yes Search -- http://master.php.net/manage/user-notes.php