--- loncom/homework/grades.pm	2008/02/01 22:50:43	1.503
+++ loncom/homework/grades.pm	2008/02/04 23:30:05	1.507
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # The LON-CAPA Grading handler
 #
-# $Id: grades.pm,v 1.503 2008/02/01 22:50:43 raeburn Exp $
+# $Id: grades.pm,v 1.507 2008/02/04 23:30:05 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -5524,6 +5524,10 @@ sub scantron_validator_positional {
     # If the split only gives us one element.. the full length of the
     # answer string, no bubbles are filled in:
 
+    if ($answers_needed eq '') {
+        return;
+    }
+
     if (length($array[0]) eq $$scantron_config{'Qlength'}*$answers_needed) {
         for (my $ans=0; $ans<$answers_needed; $ans++ ) {
             $record->{"scantron.$ansnum.answer"}='';
@@ -5950,6 +5954,8 @@ SCANTRONFORM
 	   '<input type="hidden" name="scantron.first_bubble_line.'.$line.'" value="'.$env{"form.scantron.first_bubble_line.$line"}.'" />'."\n";
        $chunk .= 
            '<input type="hidden" name="scantron.sub_bubblelines.'.$line.'" value="'.$env{"form.scantron.sub_bubblelines.$line"}.'" />'."\n";
+       $chunk .=
+           '<input type="hidden" name="scantron.responsetype.'.$line.'" value="'.$env{"form.scantron.responsetype.$line"}.'" />'."\n";
        $result .= $chunk;
        $line++;
    }
@@ -6760,7 +6766,7 @@ sub questions_to_line_list {
 	    $first   = $first_bubble_line{$question-1} + 1;
 	    $count   = $bubble_lines_per_response{$question-1};
         }
-        my $last = $first+$count-1;
+        $last = $first+$count-1;
         push(@lines, ($first..$last));
     }
     return join(',', @lines);
@@ -7260,7 +7266,25 @@ sub scantron_validate_missingbubbles {
 	# Probably here's where the error is...
 
 	foreach my $missing (@{$$scan_record{'scantron.missingerror'}}) {
-	    if ($missing > $max_bubble) { next; }
+            my $lastbubble;
+            if ($missing =~ /^(\d+)\.(\d+)$/) {
+               my $question = $1;
+               my $subquestion = $2;
+               if (!defined($first_bubble_line{$question -1})) { next; }
+               my $first = $first_bubble_line{$question-1};
+               my @subans = split(/,/,$subdivided_bubble_lines{$question-1});
+               my $subcount = 1;
+               while ($subcount<$subquestion) {
+                   $first += $subans[$subcount-1];
+                   $subcount ++;
+               }
+               my $count = $subans[$subquestion-1];
+               $lastbubble = $first + $count;
+            } else {
+                if (!defined($first_bubble_line{$missing - 1})) { next; }
+                $lastbubble = $first_bubble_line{$missing - 1} + $bubble_lines_per_response{$missing - 1};
+            }
+            if ($lastbubble > $max_bubble) { next; }
 	    push(@to_correct,$missing);
 	}
 	if (@to_correct) {