Random values from array into new array

digital_skwerl

Doing some more user ranking. Basically I am selecting the top 10% of users based on total points (being in the top 10% qualifies you to be featured), then I want to select 4 users at random from the top 10%.

I wrote this to select the top 10% of users based on their total number of bricks (ranking points). Requires a join because of my table structure (using both a user and points table)

$query2 = "SELECT COUNT(user_id) FROM users";
$result2 = @mysql_query($query2);
if ($result2) {
$row2 = @mysql_fetch_array($result2, MYSQL_NUM);
$tu = $row2[0];
if ($tu <  100) {
$pool = 10;
} else {
$pool = round($tu * .10);
}
$query4 = "SELECT users.user_id AS user, SUM(bricks.brick_num) AS brick, users.featured AS feature 
FROM users, bricks WHERE users.user_id = bricks.user_id AND users.featured = 'N' GROUP BY users.user_id ORDER BY brick DESC LIMIT $pool";
$result4 = @mysql_query($query4);
if ($result4) {
$row4 = @mysql_fetch_array($result4, MYSQL_NUM);

I now want to select 4 results at random from this array and store them in a new array. I know how to use shuffle/rand but how do I limit to 4 results? Should I just randomize and write a loop with a counter and stop at 4? Thanks.

leatherback

a suggestion:

$result2 = mysql_query($query2);
if ($result2) 
  {
  $row2 = mysql_fetch_array($result2, MYSQL_NUM); 
  $tu = $row2[0];
  $pool = floor($tu / 10);
  $pool = max(10, $pool);
  }

To grab the random values, do as you suggest, or use [man]array_rand[/man]. However, as this also requires you to loop through it to display it (Use foreach()), am not sure what the difference would be compared to a shuffle() and for() loops.

PS: Loose the @ symbols: Your code should not through errors. If itdoes, you have miscoded somewhere.

digital_skwerl

Thanks Leatherback.
My pool selection is sloppy, I will implement your suggestion. As for selecting from the array rand/foreach definitely seems appropriate, wasnt sure if it was the best way to go, but looks like it will work and thats what matters.
I will post again with the revised code.

digital_skwerl

I'm going in circles at the moment.

Could use some help getting from here:

$result4 = @mysql_query($query4);
if ($result4) {
$count = 0;
$row4 = @mysql_fetch_array($result4, MYSQL_NUM);

Randomize $row4[0] and begin loop...

To here:

$count = $count + 1;
if ($count <= 4) {		
$query1 = "SELECT first_name, last_name, city, state, thumb FROM users WHERE user_id='$user'";
$result1 = @mysql_query($query1);
if ($result1) {
$row1 = @mysql_fetch_array($result1, MYSQL_NUM);
$name = "$row1[0] $row1[1]";
$city = $row1[2];
$state = $row1[3];
$thumb = $row1[4];
echo "<tr valign=top><td width =40><a href=faculty_view.php?uid=$uid><img src=$thumb class=img1></a></td>
<td><a href=faculty_view.php?uid=$uid>$name</a><br>
$city, $state<br>
<a href=faculty_articles.php?uid=$uid>Articles</a> | <a href=faculty_message.php?uid=$uid>Contact</a></td></tr>";
}	
} else {
break;
}

Any suggestions on how to use array_rand and write the loop would be much appreciated. Otherwise I will be back to grind this over tomorrow. I think I just dont have a good understanding of arrays, time to rtfm I know.