Admin setting for stats: ranked courses get userthreshold

admin/configvars.php

@@ -578,7 +578,9 @@ class configvarrss extends configvar {
     $stats['statsruntimestart'] = new configvar (get_string('configstatsruntimestart','admin'),
       print_time_selector("statsruntimestarthour","statsruntimestartminute",make_timestamp(2000,1,1,$config->statsruntimestarthour,$config->statsruntimestartminute),5,true) );
 
-
+    $stats['statsuserthreshold'] = new configvar (get_string('configstatsuserthreshold','admin'),
+      '<input type="text" name="statsuserthreshold" size="4" value="'.$config->statsuserthreshold.'" />');
+                                              
 
 ////////////////////////////////////////////////////////////////////
 

lang/en/admin.php

@@ -105,6 +105,7 @@ $string['configsmtpuser'] = 'If you have specified an SMTP server above, and the
 $string['configstatsfirstrun'] = 'This specifies how far back the logs should be processed <b>the first time</b> the cronjob wants to process statistics. If you have a lot of traffic and are on shared hosting, it\'s probably not a good idea to go too far back, as it could take a long time to run and be quite resource intensive. (Note that for this setting, 1 month = 28 days. In the graphs and reports generated, 1 month = 1 calendar month.)';
 $string['configstatsmaxruntime'] = 'Stats processing can be quite intensive, so use a combination of this field and the next one to specify when it will run and how long for.';
 $string['configstatsruntimestart'] = 'What time should the cronjob that does the stats processing <b>start</b>?';
+$string['configstatsuserthreshold'] = 'If you enter a non-zero,  non numeric value here, for ranking courses, courses with less than this number of enrolled users (students + teachers) will be ignored';
 $string['configteacherassignteachers'] = 'Should ordinary teachers be allowed to assign other teachers within courses they teach?  If \'No\', then only course creators and admins can assign teachers.';
 $string['configthemelist'] = 'Leave this blank to allow any valid theme to be used.  If you want to shorten the theme menu, you can specify a comma-separated list of names here (Don\'t use spaces!).  
 For example:  standard,orangewhite.';

lib/statslib.php

@@ -583,6 +583,9 @@ function stats_get_parameters($time,$report,$courseid,$mode) {
         $param->fields = 'max(students+teachers) as line1,max(activestudents+activeteachers) AS line2,'
             .'max(activestudents+activeteachers)'.$real.'/max(students+teachers)'.$real.' AS line3';
         $param->extras = 'HAVING max(students+teachers) != 0';
+        if (!empty($CFG->statsuserthreshold) && is_numeric($CFG->statsuserthreshold)) {
+            $param->extras .= ' AND max(students+teachers) > '.$CFG->statsuserthreshold;
+        }
         $param->orderby = 'line3 DESC';
         $param->line1 = get_string('users');
         $param->line2 = get_string('activeusers');