Question

I want to get random numbers with exceptions (for example, I want a number from 500 to 550 without 505, 512, 525, etc).

I found here one code like this:

function randWithout($from, $to, array $exceptions) {
sort($exceptions); // lets us use break; in the foreach reliably
$number = rand($from, $to - count($exceptions)); // or mt_rand()
foreach ($exceptions as $exception) {
    if ($number >= $exception) {
        $number++; // make up for the gap
    } else {
        break;
    }
}
return $number;

}

If I use something like:

$nr = randWithout(500, 550, array(505, 512, 525));

everything it’s fine, but in array I want to put elements from mysql, so I have created:

$query = mysql_query("SELECT `site_id` FROM `table` WHERE `user_id`='{$data->id}'");
        $data = array();
        while ($issues_row = mysql_fetch_array($query, MYSQL_ASSOC)) {
        $data[] = $issues_row['site_id'];
        }
        $result = implode(",", $data);

Now, if i use:

$nr = randWithout(500, 550, array($result)); 

it’s not working, so my problem is array($result)
What is wrong here?

Answer 1

Tim is right, do not implode results in a string.

But that is the quite odd function for getting random number with exceptions. Try something like:

function getRndWithExceptions($from, $to, array $ex = array()) {
    $i = 0;
    do {
        $result = rand($from, $to);
    } while( in_array($result, $ex) && ++$i < ($to - $from) );

    if($i == ($to - $from)) return null;

    return $result;
}

<...>
$nr = getRndWithExceptions(500, 550, $data);  // $data is array