我有以下数组：

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

我想生成一个标签云，它将使在$ count中包含较高数量的艺术家在$ h6标签中包含，而在最低封闭的h1标签中。

解决方案：

从我的头顶上...

$artist = array("the roots","michael Hymanson","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.">";
}

@瑞安

没错，但实际上它会使数量最少的标签变大。此代码已经过测试：

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

也许这是一个有点学术性的话题，但是出于文档结构和其他方面的原因，hX标签可能不是标签云的最佳选择。

也许是具有适当类属性的" span"或者" ol"(外加一些CSS)？

使用了此代码段已有一段时间，信誉是Prism-perfect.net。虽然不使用H标签

<div id="tags">
    <div class="title">Popular Searches</div>
    <?php
        // Snippet taken from [prism-perfect.net]

        include "/path/to/public_html/search/settings/database.php";
        include "/path/to/public_html/search/settings/conf.php";

        $query = "SELECT query AS tag, COUNT(*) AS quantity
        FROM sphider_query_log
        WHERE results > 0
        GROUP BY query
        ORDER BY query ASC
        LIMIT 10";

        $result = mysql_query($query) or die(mysql_error());

        while ($row = mysql_fetch_array($result)) {

            $tags[$row['tag']] = $row['quantity'];
        }

        // change these font sizes if you will
        $max_size = 30; // max font size in %
        $min_size = 11; // min font size in %

        // get the largest and smallest array values
        $max_qty = max(array_values($tags));
        $min_qty = min(array_values($tags));

        // find the range of values
        $spread = $max_qty - $min_qty;
        if (0 == $spread) { // we don't want to divide by zero
            $spread = 1;
        }

        // determine the font-size increment
        // this is the increase per tag quantity (times used)
        $step = ($max_size - $min_size)/($spread);

        // loop through our tag array
        foreach ($tags as $key => $value) {

            // calculate CSS font-size
            // find the $value in excess of $min_qty
            // multiply by the font-size increment ($size)
            // and add the $min_size set above
            $size = $min_size + (($value - $min_qty) * $step);
            // uncomment if you want sizes in whole %:
            // $size = ceil($size);

            // you'll need to put the link destination in place of the /search/search.php...
            // (assuming your tag links to some sort of details page)
            echo '<a href="/search/search.php?query='.$key.'&search=1" style="font-size: '.$size.'px"';
            // perhaps adjust this title attribute for the things that are tagged
            echo ' title="'.$value.' things tagged with '.$key.'"';
            echo '>'.$key.'</a> ';
            // notice the space at the end of the link
        }
    ?>
</div>

作为Rails的帮助者：

def tag_cloud (strings, counts)
    max = counts.max
    strings.map { |a| "<span style='font-size:#{((counts[strings.index(a)] * 4.0)/max).ceil}em'>#{a}</span> "  }
end

从视图中调用此方法：

<%= tag_cloud($artists, $counts) %>

这会在数组中输出<span style =''font-size：_em''>元素，该元素将在视图中转换为字符串以最终呈现，如下所示：

<span style='font-size:3em'>the roots</span>
<span style='font-size:2em'>michael Hymanson</span> 
<span style='font-size:4em'>billy idol</span> 
<span style='font-size:1em'>more</span> 
<span style='font-size:1em'>and more</span> 
<span style='font-size:2em'>and_YET_MORE</span>

最好有一个class属性，并在上面的布伦丹(Brendan)提到的样式表中引用这些类。比从语义上使用" h1-h6"要好得多，并且带有" <span>"的样式包也更少。

我们也将想要添加对数函数。 (摘自我的Drupal模块tagadelic，以创建标签云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);
}

然后在视图或者模板中：

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

该方法适用于" SQL / PostgreSQL"狂热分子。它会完成数据库中的整个工作，并打印带有" slugified"链接的文本。它只为SQL调用使用DoctrineORM，我没有使用对象。
假设我们有10种尺寸：

public function getAllForTagCloud($fontSizes = 10)
{
    $sql = sprintf("SELECT count(tag) as tagcount,tag,slug, 
    floor((count(*) * %d )/(select max(t) from 
        (select count(tag) as t from magazine_tag group by tag) t)::numeric(6,2)) 
         as ranking 
         from magazine_tag mt group by tag,slug", $fontSizes);

    $q = Doctrine_Manager::getInstance()->getCurrentConnection();
    return $q->execute($sql);
}

然后使用一些CSS类(从.tagranking10(最好)到.tagranking1(最差))打印它们：

<?php foreach ($allTags as $tag): ?>
    <span class="<?php echo 'tagrank'.$tag['ranking'] ?>">
        <?php echo sprintf('<a rel="tag" href="/search/by/tag/%s">%s</a>', 
            $tag['slug'], $tag['tag']
        ); ?>
    </span>
<?php endforeach; ?>

这是CSS：

/* put your size of choice */
.tagrank1{font-size: 0.3em;}
.tagrank2{font-size: 0.4em;}
.tagrank3{font-size: 0.5em;} 
/* go on till tagrank10 */

此方法显示所有标签。如果有很多标签，我们可能不希望标签云成为标签风暴。在这种情况下，我们可以在SQL查询中添加一个" HAVING TO"子句：

-- minimum tag count is 8 --

HAVING count(tag) > 7

就这样