title: Create report with pageviews and unique visitors using GAPI
body: <p>I'm using GAPI to try and create simple reports from our Google Analytics data.
  My internal customer would like to see an overview with 2 fields per page: pageviews and unique visitors.
  I have the pageviews part working, but I cannot get the unique visitors part to work.
  This is my current code. The filter would be a parameter they can change, but is hardcoded for now:</p>
  
  <pre><code>require 'gapi.class.php';
  
  $ga = new gapi(ga_email,ga_password);
  
  $filter = 'pagepath =~ ^/home$';
  $ga-&gt;requestReportData(ga_profile_id,
                          array('pagepath'),
                          array('pageviews'),
                         'pageviews',
                         $filter,
                         '2010-10-01',
                         '2010-10-31');
  </code></pre>
  
  <p>and then some code to show the results which is not really relevant here.
  As said, that works, but if I add 'visitors' to the metric like this:</p>
  
  <pre><code>$ga-&gt;requestReportData(ga_profile_id,
                         array('pagepath'),
                         array('pageviews','visitors'),
                         '-pageviews',
                         $filter,
                        '2010-10-01',
                        '2010-10-31');
  </code></pre>
  
  <p>Then I get this error:</p>
  
  <pre><code>PHP Fatal error:  Uncaught exception 'Exception' with message 'GAPI: Failed to request report data. Error: "Illegal combination of dimensions and metrics"' in gapi.class.php:218
  
  Stack trace:
  #0example.filter.php(24): gapi-&gt;requestReportData('30296235', Array, Array, '-pageviews', 'pagepath =~ ^/h...', '2010-10-01', '2010-10-31')
  #1 {main}
  thrown in gapi.class.php on line 218
  </code></pre>