Discovered a bug with lesson grades. While calculating the grade, int…

…val was used to truncate the decimals from the grade. intavl is now replaced with round. round will now round the grade to 5 decimal places. The database only holds int(3). So, this has been changed to float to hold decimal numbers. We have found this to be much more accurate when converting the stored percentage in the database back to a point value (before this fix, users were getting numbers like 46.5 points instead of their original 47 points due to an inaccurate percent value). Files changed for this fix include:

locallib.php
report.php
version.php
view.php
db/mysql.php
db/mysql.sql
db/postgres7.php
db/postgres7.sql

mod/lesson/db/mysql.php

@@ -164,7 +164,9 @@ function lesson_upgrade($oldversion) {
         modify_database('','ALTER TABLE prefix_lesson_pages ADD INDEX lessonid (lessonid);');
     }
 
-
+    if ($oldversion < 2005060900) {
+        table_column('lesson_grades', 'grade', 'grade', 'float', '', 'unsigned', '0', 'not null');
+    }
 
     return true;
 }

mod/lesson/db/mysql.sql

@@ -98,7 +98,7 @@ CREATE TABLE `prefix_lesson_grades` (
   `id` int(10) unsigned NOT NULL auto_increment,
   `lessonid` int(10) unsigned NOT NULL default '0',
   `userid` int(10) unsigned NOT NULL default '0',
-  `grade` int(3) unsigned NOT NULL default '0',
+  `grade` float unsigned NOT NULL default '0',
   `late` int(3) unsigned NOT NULL default '0',
   `completed` int(10) unsigned NOT NULL default '0',
   PRIMARY KEY  (`id`),

mod/lesson/db/postgres7.php

@@ -211,6 +211,10 @@ function lesson_upgrade($oldversion) {
         modify_database('','CREATE INDEX prefix_lesson_grades_userid_idx ON prefix_lesson_grades (userid);');
         modify_database('','CREATE INDEX prefix_lesson_pages_lessonid_idx ON prefix_lesson_pages (lessonid);');
    }
+
+    if ($oldversion < 2005060900) {
+        table_column('lesson_grades', 'grade', 'grade', 'real', '', 'unsigned', '0', 'not null');
+    }
 
    return true;
 }

mod/lesson/db/postgres7.sql

@@ -87,7 +87,7 @@ CREATE TABLE prefix_lesson_grades (
   id SERIAL8 PRIMARY KEY,
   lessonid INT8  NOT NULL default '0',
   userid INT8  NOT NULL default '0',
-  grade INT  NOT NULL default '0',
+  grade real  NOT NULL default '0',
   late INT  NOT NULL default '0',
   completed INT8  NOT NULL default '0'
 ) ;

mod/lesson/locallib.php

@@ -1028,7 +1028,7 @@ function lesson_calculate_ongoing_score($lesson, $userid, $retries, $return=fals
         }
         $nviewed = count($temp); // this counts number of Questions the user viewed
         if ($nviewed != 0) {
-            $thegrade = intval(100 * $ncorrect / $nviewed);
+            $thegrade = round(100 * $ncorrect / $nviewed, 5);
         } else {
             $thegrade = 0;
         }
@@ -1093,7 +1093,7 @@ function lesson_calculate_ongoing_score($lesson, $userid, $retries, $return=fals
             }
 
             $bestscore = array_sum($bestscores);
-            $thegrade = intval(100 * $score / $bestscore);
+            $thegrade = round(100 * $score / $bestscore, 5);
         }
 
 

mod/lesson/report.php

@@ -101,7 +101,7 @@
                         // see if n is = to the retry
                         if ($n == $attempt->retry) {
                             // get grade info
-                            $usergrade = $grade->grade;
+                            $usergrade = round($grade->grade, 2); // round it here so we only have to do it once
                             break;
                         }
                         $n++; // if not equal, then increment n
@@ -802,7 +802,7 @@
                 $grade = -1;
             } else {
                 $grade = current($grades);
-                $grade = $grade->grade;
+                $grade = round($grade->grade, 2);
             }
             if (!$times = get_records_select("lesson_timer", "lessonid = $lesson->id and userid = $userid", "starttime", "*", $try, 1)) {
                 $timetotake = -1;

mod/lesson/version.php

@@ -5,7 +5,7 @@
 ///  This fragment is called by moodle_needs_upgrading() and /admin/index.php
 /////////////////////////////////////////////////////////////////////////////////
 
-$module->version  = 2005021600;  // The current module version (Date: YYYYMMDDXX)
+$module->version  = 2005060900;  // The current module version (Date: YYYYMMDDXX)
 $module->requires = 2005021600;  // Requires this Moodle version
 $module->cron     = 0;           // Period for cron to check this module (secs)
 

mod/lesson/view.php

@@ -935,7 +935,7 @@
                         }
                         echo "<p align=\"center\">".get_string("numberofcorrectanswers", "lesson", $ncorrect).
                             "</p>\n";
-                        $thegrade = intval(100 * $ncorrect / $nviewed);
+                        $thegrade = round(100 * $ncorrect / $nviewed, 5);
                         echo "<p align=\"center\">".get_string("gradeis", "lesson", 
                                 number_format($thegrade * $lesson->grade / 100, 1)).
                             " (".get_string("outof", "lesson", $lesson->grade).")</p>\n";
@@ -991,7 +991,7 @@
                             $bestscore = array_sum($bestscores);
                         }
 
-                        $thegrade = intval(100 * $score / $bestscore);
+                        $thegrade = round(100 * $score / $bestscore, 5);
                         $a = new stdClass;
                         if ($essayquestions > 0) {
                             $a->score = $score;