<div style='word-wrap: break-word; border: 3px solid red; padding:4px; width:70%; background-color:#FFFF96;'><b>Notice:</b> <i>Object of class Piwik_Date could not be converted to int</i> in <b>/var/www/html/core/Date.php</b> on line <b>59</b>
<br /><br />Backtrace --&gt;<div style="font-family:Courier;font-size:10pt">#0  Piwik_ErrorHandler(8, Object of class Piwik_Date could not be converted to int, /var/www/html/core/Date.php, 59, Array ([dateString] =&gt; Piwik_Date Object ([] =&gt; 1287683565,[] =&gt; UTC),[timezone] =&gt; )) called at [/var/www/html/core/Date.php:59]<br />
#1  Piwik_Date::factory(Piwik_Date Object ([] =&gt; 1287683565,[] =&gt; UTC)) called at [/var/www/html/plugins/PDFReports/API.php:245]<br />
#2  Piwik_PDFReports_API-&gt;generateReport(6, Piwik_Date Object ([] =&gt; 1287683565,[] =&gt; UTC), 3, 2) called at [/var/www/html/plugins/PDFReports/API.php:315]<br />
#3  Piwik_PDFReports_API-&gt;sendEmailReport(6, 3)<br />
#4  call_user_func_array(Array ([0] =&gt; Piwik_PDFReports_API Object ([] =&gt; Array ()),[1] =&gt; sendEmailReport), Array ([0] =&gt; 6,[1] =&gt; 3)) called at [/var/www/html/core/API/Proxy.php:151]<br />
#5  Piwik_API_Proxy-&gt;call(Piwik_PDFReports_API, sendEmailReport, Array ([token_auth] =&gt; XXXXXXXXXX,[idSite] =&gt; 3,[module] =&gt; API,[method] =&gt; PDFReports.sendEmailReport,[format] =&gt; json,[idReport] =&gt; 6,[filter_limit] =&gt; 50)) called at [/var/www/html/core/API/Request.php:117]<br />
#6  Piwik_API_Request-&gt;process() called at [/var/www/html/plugins/API/Controller.php:27]<br />
#7  Piwik_API_Controller-&gt;index()<br />
#8  call_user_func_array(Array ([0] =&gt; Piwik_API_Controller Object ([] =&gt; API,[] =&gt; ,[] =&gt; ,[] =&gt; 3,[] =&gt; ),[1] =&gt; index), Array ()) called at [/var/www/html/core/FrontController.php:126]<br />
#9  Piwik_FrontController-&gt;dispatch() called at [/var/www/html/index.php:60]<br />
</div><br /><br />
</pre></div><br />

Piwik_PDFReports_API::getInstance()->generateReport(
    $idReport,
    Piwik_Date::now()->subPeriod(1, $report['period']),
    $idSite,
    $outputType = Piwik_PDFReports_API::OUTPUT_PDF_SAVE_ON_DISK
);

Piwik_PDFReports_API::getInstance()->generateReport(
    $idReport,
    Piwik_Date::now()->subPeriod(1, $report['period'])->toString(),
    $idSite,
    $outputType = Piwik_PDFReports_API::OUTPUT_PDF_SAVE_ON_DISK
);