title: simple_xml get max value of attribute
body: <p>I'm trying to get the maximum and the minimum value of the option-node for each item in the following xml (snippet):</p>
  
  <pre><code>&lt;body&gt;
      &lt;page number="1"&gt;
          &lt;itemset name="a"&gt;
              &lt;item id="1"&gt;
                 &lt;option value="0"&gt;no&lt;/option&gt;
                 &lt;option value="1"&gt;rarely&lt;/option&gt;
                 &lt;option value="3"&gt;sometimes&lt;/option&gt;
                 &lt;option value="5"&gt;often&lt;/option&gt;
                 &lt;scale id="ho" /&gt;
              &lt;/item&gt;
              &lt;item id="2"&gt;
                  &lt;option value="0"&gt;no&lt;/option&gt;
                  &lt;option value="1"&gt;rarely&lt;/option&gt;
                  &lt;option value="3"&gt;sometimes&lt;/option&gt;
                  &lt;option value="5"&gt;often&lt;/option&gt;
                  &lt;scale id="hi" /&gt;
              &lt;/item&gt;
          &lt;/itemset&gt;
      &lt;/page&gt;
  &lt;/body&gt;
  </code></pre>
  
  <p>I'm doing this within a foreach-loop...</p>
  
  <pre><code>...
  
  $scid="ho";
  $total=0;
  $count=0;
  
  foreach ($txml-&gt;xpath("//item[scale/@id='$scid']") as $item) {
      $score=$rxml-&gt;xpath("//item[@id='".$item['id']."']"); // get a value from another simple_xml-object
  $total+=intval($score[0]);
  $count++;
  // ******* problem starts here...           
  $values = $item-&gt;option['value'];
  // doing sth with $values to get max and min value
      echo '&lt;pre&gt;'; 
      print_r($values); // ******* 
      echo '&lt;/pre&gt;';
  } // foreach $item
  
  ...
  </code></pre>
  
  <p>What I get in <code>$values</code> is</p>
  
  <pre><code>SimpleXMLElement Object
  (
      [0] =&gt; 0
  )
  </code></pre>
  
  <p>with <code>$values = $item-&gt;xpath('option[@value]');</code> instead, I get...</p>
  
  <pre><code>    Array
  (
      [0] =&gt; SimpleXMLElement Object
      (
          [@attributes] =&gt; Array
              (
                  [value] =&gt; 0
              )
  
      )
  
      [1] =&gt; SimpleXMLElement Object
      (
          [@attributes] =&gt; Array
              (
                  [value] =&gt; 1
              )
  
      )
  
      [2] =&gt; SimpleXMLElement Object
      (
          [@attributes] =&gt; Array
              (
                  [value] =&gt; 3
              )
  
      )
  
      [3] =&gt; SimpleXMLElement Object
      (
          [@attributes] =&gt; Array
              (
                  [value] =&gt; 5
              )
  
      )
  
  )
  </code></pre>
  
  <p>I am looking for a more straightforward solution - or how to get min and max from there.</p>
  
  <p>I'd like to get sth like <code>$values['max']=5</code> and <code>$values['min']=0</code></p>
  
  <p>Thank you in advance,</p>
  
  <p>Michi</p>
  
  <p>PS: as I wasn't able to get this working with simple_xml and didn't want to switch to DOM, I decided to do it quick and dirty with some basic PHP:</p>
  
  <pre><code>foreach ($item-&gt;xpath("//item[@id='".$item['id']."']/option/@value") as $value) {
      $v[]=(int)$value-&gt;value;
  }
  echo max($v);
  echo min($v);
  </code></pre>