--- loncom/interface/spreadsheet/studentcalc.pm	2003/07/16 15:57:32	1.14
+++ loncom/interface/spreadsheet/studentcalc.pm	2003/12/05 22:24:20	1.16.2.1
@@ -1,5 +1,5 @@
 #
-# $Id: studentcalc.pm,v 1.14 2003/07/16 15:57:32 matthew Exp $
+# $Id: studentcalc.pm,v 1.16.2.1 2003/12/05 22:24:20 matthew Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -174,6 +174,10 @@ sub outsheet_html {
     my $editing_is_allowed = &Apache::lonnet::allowed('mgr',
                                                 $ENV{'request.course.id'});
     ####################################
+    # Report any calculation errors    #
+    ####################################
+    $r->print($self->html_report_error());
+    ####################################
     # Determine table structure        #
     ####################################
     my $num_uneditable = 26;
@@ -411,7 +415,6 @@ sub outsheet_recursive_excel {
 
 sub compute {
     my $self = shift;
-    $self->logthis('computing');
     if (! defined($current_course) ||
         $current_course ne $ENV{'request.course.id'}) {
         $current_course = $ENV{'request.course.id'};
@@ -453,6 +456,12 @@ sub compute {
                                                       $assess_filename,
                                                       $resource->{'symb'});
             my @exportdata = $assessSheet->export_data();
+            if ($assessSheet->badcalc()) {
+                $self->set_calcerror(
+            'Error computing row for assessment '.
+                $assessSheet->get_title().'(row '.$rownum.'):'.
+                                     $assessSheet->calcerror());
+            }
             if ($assessSheet->blackout()) {
                 $self->blackout(1);
                 $self->{'blackout_rows'}->{$rownum} = 1;
@@ -582,6 +591,11 @@ sub save_export_data {
     my $self = shift;
     return if ($self->temporary());
     my $student = $self->{'name'}.':'.$self->{'domain'};
+    if ($self->badcalc()){
+        # do not save data away when calculations have not been done properly.
+        delete($Exportrows{$student});
+        return;
+    }
     return if (! exists($Exportrows{$student}));
     return if (! $self->is_default());
     my $key = join(':',($self->{'name'},$self->{'domain'},'studentcalc')).':';
@@ -589,7 +603,7 @@ sub save_export_data {
     my $newstore = join('___;___',
                         @{$Exportrows{$student}->{'data'}});
     $newstore = '___=___'.$newstore;
-    &Apache::lonnet::put('nohist_calculatedsheets',
+    my $result= &Apache::lonnet::put('nohist_calculatedsheets',
                          { $key     => $newstore,
                            $timekey => $Exportrows{$student}->{'time'} },
                          $self->{'cdom'},
@@ -615,12 +629,24 @@ sub export_data {
     my $self = shift;
     my $student = $self->{'name'}.':'.$self->{'domain'};
     if (! exists($Exportrows{$student}) ||
+        ! defined($Exportrows{$student}) ||
+        ! exists($Exportrows{$student}->{'data'}) ||
+        ! defined($Exportrows{$student}->{'data'}) ||
+        ! exists($Exportrows{$student}->{'time'}) ||
+        ! defined($Exportrows{$student}->{'time'}) ||
         ! $self->check_expiration_time($Exportrows{$student}->{'time'})) {
         $self->compute();
     }
-    my @Data = @{$Exportrows{$student}->{'data'}};
-    for (my $i=0; $i<=$#Data;$i++) {
-        $Data[$i]="'".$Data[$i]."'" if ($Data[$i]=~/\D/ && defined($Data[$i]));
+    my @Data;
+    if ($self->badcalc()) {
+        @Data = ();
+    } else {
+        @Data = @{$Exportrows{$student}->{'data'}};
+        for (my $i=0; $i<=$#Data;$i++) {
+            if ($Data[$i]=~/\D/ && defined($Data[$i])) {
+                $Data[$i]="'".$Data[$i]."'";
+            }
+        }
     }
     return @Data;
 }