What's the best way to generate a tag cloud from an array using h1 through h6 for sizing?

Question

I have the following arrays:

$artist = array("the roots", "michael jackson", "billy idol", "more", "and more", "and_YET_MORE");
$count = array(5, 3, 9, 1, 1, 3);

I want to generate a tag cloud that will have artists with a higher number in $count enclosed in h6 tags and the lowest enclosed h1 tags.

Answer 1

You will want to add a logarithmic function to it too. (taken from tagadelic, my Drupal module to create tag clouds http://drupal.org/project/tagadelic):

db_query('SELECT COUNT(*) AS count, id, name FROM ... ORDER BY count DESC');

$steps = 6;
$tags = array();
$min = 1e9;
$max = -1e9;

while ($tag = db_fetch_object($result)) {
    $tag->number_of_posts = $tag->count; #sets the amount of items a certain tag has attached to it
    $tag->count = log($tag->count);
    $min = min($min, $tag->count);
    $max = max($max, $tag->count);
    $tags[$tag->tid] = $tag;
}
// Note: we need to ensure the range is slightly too large to make sure even
// the largest element is rounded down.
$range = max(.01, $max - $min) * 1.0001;

foreach ($tags as $key => $value) {
    $tags[$key]->weight = 1 + floor($steps * ($value->count - $min) / $range);
}

Then in your view or template:

foreach ($tags as $tag) {
    $output .= "<h$tag->weight>$tag->name</h$tag->weight>"
}

Answer 2

Off the top of my head...

$artist = array("the roots","michael jackson","billy idol","more","and more","and_YET_MORE");
$count = array(5,3,9,1,1,3);
$highest = max($count);
for (int $x = 0; $x < count($artist); $x++)
{
    $normalized = $count[$x] / $highest;
    $heading = ceil($normalized * 6); // 6 heading types
    echo "<h".$heading.">".$artist[$x]."</h".$heading.">";
}

Answer 3

Perhaps this is a little academic and off topic but hX tags are probably not the best choice for a tag cloud for reasons of document structure and all that sort of thing.

Maybe spans or an ol with appropriate class attributes (plus some CSS)?