--- loncom/metadata_database/LONCAPA/lonmetadata.pm	2004/04/14 20:35:29	1.7
+++ loncom/metadata_database/LONCAPA/lonmetadata.pm	2004/04/16 21:43:56	1.8
@@ -1,6 +1,6 @@
 # The LearningOnline Network with CAPA
 #
-# $Id: lonmetadata.pm,v 1.7 2004/04/14 20:35:29 matthew Exp $
+# $Id: lonmetadata.pm,v 1.8 2004/04/16 21:43:56 matthew Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -410,6 +410,48 @@ sub metadata_col_to_hash {
 
 =pod
 
+=item nohist_resevaldata.db data structure
+
+The nohist_resevaldata.db file has the following possible keys:
+
+ Statistics Data (values are integers, perl times, or real numbers)
+ ------------------------------------------
+ $course___$resource___avetries
+ $course___$resource___count
+ $course___$resource___difficulty
+ $course___$resource___stdno
+ $course___$resource___timestamp
+
+ Evaluation Data (values are on a 1 to 5 scale)
+ ------------------------------------------
+ $username@$dom___$resource___clear
+ $username@$dom___$resource___comments
+ $username@$dom___$resource___depth
+ $username@$dom___$resource___technical
+ $username@$dom___$resource___helpful
+
+ Course Context Data
+ ------------------------------------------
+ $course___$resource___course       course id
+ $course___$resource___comefrom     resource preceeding this resource
+ $course___$resource___goto         resource following this resource
+ $course___$resource___usage        resource containing this resource
+
+ New statistical data storage
+ ------------------------------------------
+ $course&$sec&$numstud___$resource___stats
+    $sec is a string describing the sections: all, 1 2, 1 2 3,...
+    Value is a '&' deliminated list of key=value pairs.
+    Possible keys are (currently) disc,course,sections,difficulty, 
+    stdno, timestamp
+
+=cut
+
+######################################################################
+######################################################################
+
+=pod
+
 =item &process_reseval_data 
 
 Process a nohist_resevaldata hash into a more complex data structure.
@@ -474,13 +516,15 @@ sub process_reseval_data {
             # $source is $cid\_$sec\_$stdno
             # $value is stat1=value&stat2=value&stat3=value,....
             #
-            my ($cid,$sec,$stdno)=split('_',$source);
-            my $crssec = $cid.'_'.$sec;
+            my ($cid,$sec,$stdno)=split('&',$source);
+            my $crssec = $cid.'&'.$sec;
             my @Data = split('&',$value);
             my %Statistics;
             while (my ($key,$value) = split('=',pop(@Data))) {
                 $Statistics{$key} = $value;
             }
+            $sec =~ s:("$|^")::g;
+            $Statistics{'sections'} = $sec;
             #
             # Only store the data if the number of students is greater
             # than the data already stored
@@ -522,26 +566,71 @@ sub process_dynamic_metadata {
     my %data;
     my $resdata = $DynamicData->{$url};
     #
-    # Get the statistical data
-    foreach my $type (qw/avetries difficulty stdno/) {
-        my $count;
+    # Get the statistical data - Use a weighted average
+    foreach my $type (qw/avetries difficulty disc/) {
+        my $studentcount;
         my $sum;
         my @Values;
+        my @Students;
         #
+        # Old data
         foreach my $coursedata (values(%{$resdata->{'statistics'}}),
                                 values(%{$resdata->{'stats'}})) {
             if (ref($coursedata) eq 'HASH' && exists($coursedata->{$type})) {
-                $count++;
-                $sum += $coursedata->{$type};
+                $studentcount += $coursedata->{'stdno'};
+                $sum += ($coursedata->{$type}*$coursedata->{'stdno'});
                 push(@Values,$coursedata->{$type});
+                push(@Students,$coursedata->{'stdno'});
             }
         }
-        if ($count) {
-            $data{$type} = $sum/$count;
+        if (exists($resdata->{'stats'})) {
+            foreach my $identifier (sort(keys(%{$resdata->{'stats'}}))) {
+                my $coursedata = $resdata->{'stats'}->{$identifier};
+                $studentcount += $coursedata->{'stdno'};
+                $sum += $coursedata->{$type}*$coursedata->{'stdno'};
+                push(@Values,$coursedata->{$type});                
+                push(@Students,$coursedata->{'stdno'});
+            }
+        }
+        #
+        # New data
+        if (defined($studentcount) && $studentcount>0) {
+            $data{$type} = $sum/$studentcount;
             $data{$type.'_list'} = join(',',@Values);
         }
     }
     #
+    # Find out the number of students who have completed the resource...
+    my $stdno;
+    foreach my $coursedata (values(%{$resdata->{'statistics'}}),
+                            values(%{$resdata->{'stats'}})) {
+        if (ref($coursedata) eq 'HASH' && exists($coursedata->{'stdno'})) {
+            $stdno += $coursedata->{'stdno'};
+        }
+    }
+    if (exists($resdata->{'stats'})) {
+        #
+        # For the number of students, take the maximum found for the class
+        my $current_course;
+        my $coursemax=0;
+        foreach my $identifier (sort(keys(%{$resdata->{'stats'}}))) {
+            my $coursedata = $resdata->{'stats'}->{$identifier};
+            if (! defined($current_course)) {
+                $current_course = $coursedata->{'course'};
+            }
+            if ($current_course ne $coursedata->{'course'}) {
+                $stdno += $coursemax;
+                $coursemax = 0;
+                $current_course = $coursedata->{'course'};                
+            }
+            if ($coursemax < $coursedata->{'stdno'}) {
+                $coursemax = $coursedata->{'stdno'};
+            }
+        }
+        $stdno += $coursemax; # pick up the final course in the list
+    }
+    $data{'stdno'}=$stdno;
+    #
     # Get the context data
     foreach my $type (qw/course goto comefrom/) {
         if (defined($resdata->{$type}) && 
@@ -581,9 +670,33 @@ sub process_dynamic_metadata {
     $comments .= '</div>';
     $data{'comments'} = $comments;
     #
+    if (exists($resdata->{'stats'})) {
+        $data{'stats'} = $resdata->{'stats'};
+    }
+    #
     return %data;
 }
 
+sub dynamic_metadata_storage {
+    my ($data) = @_;
+    my %Store;
+    my $courseid = $data->{'course'};
+    my $sections = $data->{'sections'};
+    my $numstu = $data->{'num_students'};
+    my $urlres = $data->{'urlres'};
+    my $key = $courseid.'&'.$sections.'&'.$numstu.'___'.$urlres.'___stats';
+    $Store{$key} =
+        'course='.$courseid.'&'.
+        'sections='.$sections.'&'.
+        'timestamp='.time.'&'.
+        'stdno='.$data->{'num_students'}.'&'.
+        'avetries='.$data->{'mean_tries'}.'&'.
+        'difficulty='.$data->{'deg_of_diff'};
+    if (exists($data->{'deg_of_disc'})) {
+        $Store{$key} .= '&'.'disc='.$data->{'deg_of_disc'};
+    }
+    return %Store;
+}
 
 ######################################################################
 ######################################################################