Changeset 1119 for trunk/common

Timestamp:

03/24/10 22:01:03 (2 years ago)

Author:

wefgef

Message:

Adds a new difficulty column for Tasks macro.

Also made a minor change in the look of the table.

REVIEW URL: ​http://reviewboard.infoarena.ro/r/144/

Location:

trunk/common

Files:

• db/round.php (modified) (1 diff)
• task_rating.php (modified) (1 diff)

trunk/common/db/round.php

@@ -118 +118 @@
               "task.`type` AS `type`,
                task.`open_source` AS `open_source`,
-               task.`open_tests` AS `open_tests`";
+               task.`open_tests` AS `open_tests`,
+               task.`rating` AS `rating`";
     if ($user_id == null || $fetch_scores == false) {
         $query = sprintf("SELECT $fields

trunk/common/task_rating.php

@@ -2 +2 @@
 
 require_once(IA_ROOT_DIR."common/db/task_rating.php");
+require_once(IA_ROOT_DIR."common/rating.php");
 
 // Computes the rating out of the array $ratings
 // $ratings contains arrays of ratings
-// FIXME: use smarter task rating function
 function task_rating_compute($ratings) {
-    $sum = 0;
-    $nr = 0;
+    $idea = 0.0;
+    $theory = 0.0;
+    $coding = 0.0;
 
+    // Compute average ratings for each category
     foreach ($ratings as $rating) {
-        $sum += $rating['idea'] + $rating['theory'] + $rating['coding'];
-        $nr += 3;
+        $idea += $rating['idea'];
+        $theory += $rating['theory'];
+        $coding += $rating['coding'];
     }
+    $idea /= count($ratings);
+    $theory /= count($ratings);
+    $coding /= count($ratings);
 
-    $task_rating = 1.0 * $sum / $nr;
+    $best = max($idea, $theory, $coding);
 
-    return $task_rating;
+    // Compute a weighted sum of the three ratings
+    $weight_idea = sqr($idea / $best);
+    $weight_theory = sqr($theory / $best);
+    $weight_coding = sqr($coding / $best);
+
+    $final_grade = ($weight_idea * $idea +
+                    $weight_theory * $theory +
+                    $weight_coding * $coding) /
+                   ($weight_idea + $weight_theory + $weight_coding);
+
+    // Find proper difficulty number
+    $cut_offs = array(3.40, 4.00, 5.00, 6.00, 10.00);
+    for ($i = 0; $i < count($cut_offs); ++$i)
+      if ($cut_offs[$i] >= $final_grade)
+        return $i + 1;
 }