--- loncom/interface/statistics/lonproblemanalysis.pm	2005/03/14 20:28:22	1.118
+++ loncom/interface/statistics/lonproblemanalysis.pm	2005/03/15 00:51:43	1.119
@@ -1,6 +1,6 @@
 # The LearningOnline Network with CAPA
 #
-# $Id: lonproblemanalysis.pm,v 1.118 2005/03/14 20:28:22 matthew Exp $
+# $Id: lonproblemanalysis.pm,v 1.119 2005/03/15 00:51:43 matthew Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -482,8 +482,12 @@ sub numerical_classify_responses {
         if ($stats{'max_abs'} < $abs_high) {
             $stats{'max_abs'} = $abs_high;
         }
-        my $low_percent  = 100 * abs($abs_low  / $subm{'correct'});
-        my $high_percent = 100 * abs($abs_high / $subm{'correct'});
+        my $low_percent;
+        my $high_percent;
+        if (defined($subm{'correct'}) && $subm{'correct'} != 0) {
+            $low_percent  = 100 * abs($abs_low  / $subm{'correct'});
+            $high_percent = 100 * abs($abs_high / $subm{'correct'});
+        }
         if (! defined($stats{'min_percent'}) ||
             $stats{'min_percent'} > $low_percent) {
             $stats{'min_percent'} = $low_percent;
@@ -531,6 +535,8 @@ sub numerical_classify_responses {
             }
         }
     }
+    $stats{'correct_count'} |= 0;
+    $stats{'incorrect_count'} |= 0;
     $stats{'students'}=scalar(keys(%students));
     return (\%submission_data,\%stats);
 }
@@ -882,16 +888,14 @@ sub radio_response_analysis {
             $choice_plot  ne '' ||
             $stacked_plot ne '') {
             my $correct = $foil_choice_data->{'_correct'};
-            if (! defined($correct) || $correct eq '') {
-                $correct = 0;
-            }
-            my $incorrect = 
+            $correct |= 0;
+            my $incorrect = $foil_choice_data->{'_count'}-$correct;
             $analysis_html.= '<tr><td colspan="4" align="center">'.
                 '<font size="+1">'.
                 &mt($pre_graph_text,
                     $plot_num,$foil_choice_data->{'_count'},
                     $correct,
-                    $foil_choice_data->{'_count'}-$correct,
+                    $incorrect,
                     $foil_choice_data->{'_students'},
                     @extra_data).
                     '</td></tr>'.$/;
@@ -1309,7 +1313,7 @@ sub OR_tries_analysis {
         # Create Foil Plots
         my $data_count = $response_data{'_total'}->[$try];
         my $correct = $response_data{'_correct'}->[$try];
-        if (! defined($correct)) { $correct = 0; }
+        $correct |= 0;
         my @Datasets;
         foreach my $option ('_correct',@{$ORdata->{'_Options'}}) {
             next if (! exists($foil_plot[$try]->{$option}));
@@ -1472,6 +1476,7 @@ sub OR_time_analysis {
         ##
         my ($processed_time_data,$correct,$data_count,$student_count) =
             &OR_time_process_data($performance_data,$begin_index,$end_index);
+        $correct |= 0;
         ##
         $table .= '<tr><td colspan="4" align="center"><font size="+1">'.
             &mt('[_1] submissions from [_2] students, [_3] correct, [_4] incorrect',