--- loncom/interface/Attic/lonspreadsheet.pm	2001/03/10 16:46:52	1.41
+++ loncom/interface/Attic/lonspreadsheet.pm	2002/08/29 15:35:01	1.103
@@ -1,10 +1,65 @@
+#
+# $Id: lonspreadsheet.pm,v 1.103 2002/08/29 15:35:01 matthew Exp $
+#
+# Copyright Michigan State University Board of Trustees
+#
+# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
+#
+# LON-CAPA is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# LON-CAPA is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with LON-CAPA; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+#
+# /home/httpd/html/adm/gpl.txt
+#
+# http://www.lon-capa.org/
+#
 # The LearningOnline Network with CAPA
 # Spreadsheet/Grades Display Handler
 #
 # 11/11,11/15,11/27,12/04,12/05,12/06,12/07,
 # 12/08,12/09,12/11,12/12,12/15,12/16,12/18,12/19,12/30,
 # 01/01/01,02/01,03/01,19/01,20/01,22/01,
-# 03/05,03/08,03/10 Gerd Kortemeyer
+# 03/05,03/08,03/10,03/12,03/13,03/15,03/17,
+# 03/19,03/20,03/21,03/27,04/05,04/09,
+# 07/09,07/14,07/21,09/01,09/10,9/11,9/12,9/13,9/14,9/17,
+# 10/16,10/17,10/20,11/05,11/28,12/27 Gerd Kortemeyer
+# 01/14/02 Matthew
+# 02/04/02 Matthew
+
+# POD required stuff:
+
+=head1 NAME
+
+lonspreadsheet
+
+=head1 SYNOPSIS
+
+Spreadsheet interface to internal LON-CAPA data
+
+=head1 DESCRIPTION
+
+Lonspreadsheet provides course coordinators the ability to manage their
+students grades online.  The students are able to view their own grades, but
+not the grades of their peers.  The spreadsheet is highly customizable,
+offering the ability to use Perl code to manipulate data, as well as many
+built-in functions.
+
+
+=head2 Functions available to user of lonspreadsheet
+
+=over 4
+
+=cut
 
 package Apache::lonspreadsheet;
             
@@ -16,6 +71,14 @@ use Apache::lonnet;
 use Apache::Constants qw(:common :http);
 use GDBM_File;
 use HTML::TokeParser;
+use Apache::lonhtmlcommon;
+#
+# Caches for previously calculated spreadsheets
+#
+
+my %oldsheets;
+my %loadedcaches;
+my %expiredates;
 
 #
 # Cache for stores of an individual user
@@ -43,6 +106,14 @@ my %courseopt;
 my %useropt;
 my %parmhash;
 
+#
+# Some hashes for stats on timing and performance
+#
+
+my %starttimes;
+my %usedtimes;
+my %numbertimes;
+
 # Stuff that only the screen handler can know
 
 my $includedir;
@@ -59,6 +130,7 @@ sub initsheet {
     $safeeval->permit("sort");
     $safeeval->deny(":base_io");
     $safehole->wrap(\&Apache::lonnet::EXT,$safeeval,'&EXT');
+    $safeeval->share('$@');
     my $code=<<'ENDDEFS';
 # ---------------------------------------------------- Inside of the safe space
 
@@ -68,12 +140,14 @@ sub initsheet {
 # v: output values
 # c: preloaded constants (A-column)
 # rl: row label
+# os: other spreadsheets (for student spreadsheet only)
 
 undef %v; 
 undef %t;
 undef %f;
 undef %c;
-undef %rl;
+undef %rowlabel;
+undef @os;
 
 $maxrow=0;
 $sheettype='';
@@ -100,6 +174,10 @@ $cfn='';
 
 $usymb='';
 
+# error messages
+
+$errormsg='';
+
 sub mask {
     my ($lower,$upper)=@_;
 
@@ -129,16 +207,16 @@ sub mask {
     } else {
         if (length($ld)!=length($ud)) {
            $num.='(';
-	   map {
+	   foreach ($ld=~m/\d/g) {
               $num.='['.$_.'-9]';
-           } ($ld=~m/\d/g);
+	   }
            if (length($ud)-length($ld)>1) {
               $num.='|\d{'.(length($ld)+1).','.(length($ud)-1).'}';
 	   }
            $num.='|';
-           map {
+           foreach ($ud=~m/\d/g) {
                $num.='[0-'.$_.']';
-           } ($ud=~m/\d/g);
+           }
            $num.=')';
        } else {
            my @lda=($ld=~m/\d/g);
@@ -176,12 +254,285 @@ sub mask {
     return '^'.$alpha.$num."\$";
 }
 
+#-------------------------------------------------------
+
+=item UWCALC(hashname,modules,units,date) 
+
+returns the proportion of the module 
+weights not previously completed by the student.
+
+=over 4
+
+=item hashname 
+
+name of the hash the module dates have been inserted into
+
+=item modules 
+
+reference to a cell which contains a comma deliminated list of modules 
+covered by the assignment.
+
+=item units 
+
+reference to a cell which contains a comma deliminated list of module 
+weights with respect to the assignment
+
+=item date 
+
+reference to a cell which contains the date the assignment was completed.
+
+=back 
+
+=cut
+
+#-------------------------------------------------------
+sub UWCALC {
+    my ($hashname,$modules,$units,$date) = @_;
+    my @Modules = split(/,/,$modules);
+    my @Units   = split(/,/,$units);
+    my $total_weight;
+    foreach (@Units) {
+	$total_weight += $_;
+    }
+    my $usum=0;
+    for (my $i=0; $i<=$#Modules; $i++) {
+	if (&HASH($hashname,$Modules[$i]) eq $date) {
+	    $usum += $Units[$i];
+	}
+    }
+    return $usum/$total_weight;
+}
+
+#-------------------------------------------------------
+
+=item CDLSUM(list) 
+
+returns the sum of the elements in a cell which contains
+a Comma Deliminate List of numerical values.
+'list' is a reference to a cell which contains a comma deliminated list.
+
+=cut
+
+#-------------------------------------------------------
+sub CDLSUM {
+    my ($list)=@_;
+    my $sum;
+    foreach (split/,/,$list) {
+	$sum += $_;
+    }
+    return $sum;
+}
+
+#-------------------------------------------------------
+
+=item CDLITEM(list,index) 
+
+returns the item at 'index' in a Comma Deliminated List.
+
+=over 4
+
+=item list
+
+reference to a cell which contains a comma deliminated list.
+
+=item index 
+
+the Perl index of the item requested (first element in list has
+an index of 0) 
+
+=back
+
+=cut
+
+#-------------------------------------------------------
+sub CDLITEM {
+    my ($list,$index)=@_;
+    my @Temp = split/,/,$list;
+    return $Temp[$index];
+}
+
+#-------------------------------------------------------
+
+=item CDLHASH(name,key,value) 
+
+loads a comma deliminated list of keys into
+the hash 'name', all with a value of 'value'.
+
+=over 4
+
+=item name  
+
+name of the hash.
+
+=item key
+
+(a pointer to) a comma deliminated list of keys.
+
+=item value
+
+a single value to be entered for each key.
+
+=back
+
+=cut
+
+#-------------------------------------------------------
+sub CDLHASH {
+    my ($name,$key,$value)=@_;
+    my @Keys;
+    my @Values;
+    # Check to see if we have multiple $key values
+    if ($key =~ /[A-z](\-[A-z])?\d+(\-\d+)?/) {
+	my $keymask = &mask($key);
+	# Assume the keys are addresses
+	my @Temp = grep /$keymask/,keys(%v);
+	@Keys = $v{@Temp};
+    } else {
+	$Keys[0]= $key;
+    }
+    my @Temp;
+    foreach $key (@Keys) {
+	@Temp = (@Temp, split/,/,$key);
+    }
+    @Keys = @Temp;
+    if ($value =~ /[A-z](\-[A-z])?\d+(\-\d+)?/) {
+	my $valmask = &mask($value);
+	my @Temp = grep /$valmask/,keys(%v);
+	@Values =$v{@Temp};
+    } else {
+	$Values[0]= $value;
+    }
+    $value = $Values[0];
+    # Add values to hash
+    for (my $i = 0; $i<=$#Keys; $i++) {
+	my $key   = $Keys[$i];
+	if (! exists ($hashes{$name}->{$key})) {
+	    $hashes{$name}->{$key}->[0]=$value;
+	} else {
+	    my @Temp = sort(@{$hashes{$name}->{$key}},$value);
+	    $hashes{$name}->{$key} = \@Temp;
+	}
+    }
+    return "hash '$name' updated";
+}
+
+#-------------------------------------------------------
+
+=item GETHASH(name,key,index) 
+
+returns the element in hash 'name' 
+reference by the key 'key', at index 'index' in the values list.
+
+=cut
+
+#-------------------------------------------------------
+sub GETHASH {
+    my ($name,$key,$index)=@_;
+    if (! defined($index)) {
+	$index = 0;
+    }
+    if ($key =~ /^[A-z]\d+$/) {
+	$key = $v{$key};
+    }
+    return $hashes{$name}->{$key}->[$index];
+}
+
+#-------------------------------------------------------
+
+=item CLEARHASH(name) 
+
+clears all the values from the hash 'name'
+
+=item CLEARHASH(name,key) 
+
+clears all the values from the hash 'name' associated with the given key.
+
+=cut
+
+#-------------------------------------------------------
+sub CLEARHASH {
+    my ($name,$key)=@_;
+    if (defined($key)) {
+	if (exists($hashes{$name}->{$key})) {
+	    $hashes{$name}->{$key}=undef;
+	    return "hash '$name' key '$key' cleared";
+	}
+    } else {
+	if (exists($hashes{$name})) {
+	    $hashes{$name}=undef;
+	    return "hash '$name' cleared";
+	}
+    }
+    return "Error in clearing hash";
+}
+
+#-------------------------------------------------------
+
+=item HASH(name,key,value) 
+
+loads values into an internal hash.  If a key 
+already has a value associated with it, the values are sorted numerically.  
+
+=item HASH(name,key) 
+
+returns the 0th value in the hash 'name' associated with 'key'.
+
+=cut
+
+#-------------------------------------------------------
+sub HASH {
+    my ($name,$key,$value)=@_;
+    my @Keys;
+    undef @Keys;
+    my @Values;
+    # Check to see if we have multiple $key values
+    if ($key =~ /[A-z](\-[A-z])?\d+(\-\d+)?/) {
+	my $keymask = &mask($key);
+	# Assume the keys are addresses
+	my @Temp = grep /$keymask/,keys(%v);
+	@Keys = $v{@Temp};
+    } else {
+	$Keys[0]= $key;
+    }
+    # If $value is empty, return the first value associated 
+    # with the first key.
+    if (! $value) {
+	return $hashes{$name}->{$Keys[0]}->[0];
+    }
+    # Check to see if we have multiple $value(s) 
+    if ($value =~ /[A-z](\-[A-z])?\d+(\-\d+)?/) {
+	my $valmask = &mask($value);
+	my @Temp = grep /$valmask/,keys(%v);
+	@Values =$v{@Temp};
+    } else {
+	$Values[0]= $value;
+    }
+    # Add values to hash
+    for (my $i = 0; $i<=$#Keys; $i++) {
+	my $key   = $Keys[$i];
+	my $value = ($i<=$#Values ? $Values[$i] : $Values[0]);
+	if (! exists ($hashes{$name}->{$key})) {
+	    $hashes{$name}->{$key}->[0]=$value;
+	} else {
+	    my @Temp = sort(@{$hashes{$name}->{$key}},$value);
+	    $hashes{$name}->{$key} = \@Temp;
+	}
+    }
+    return $Values[-1];
+}
+
+#-------------------------------------------------------
+
+=item NUM(range)
+
+returns the number of items in the range.
+
+=cut
+
+#-------------------------------------------------------
 sub NUM {
     my $mask=mask(@_);
-    my $num=0;
-    map {
-        $num++;
-    } grep /$mask/,keys %v;
+    my $num= $#{@{grep(/$mask/,keys(%v))}}+1;
     return $num;   
 }
 
@@ -189,31 +540,49 @@ sub BIN {
     my ($low,$high,$lower,$upper)=@_;
     my $mask=mask($lower,$upper);
     my $num=0;
-    map {
+    foreach (grep /$mask/,keys(%v)) {
         if (($v{$_}>=$low) && ($v{$_}<=$high)) {
             $num++;
         }
-    } grep /$mask/,keys %v;
+    }
     return $num;   
 }
 
 
+#-------------------------------------------------------
+
+=item SUM(range)
+
+returns the sum of items in the range.
+
+=cut
+
+#-------------------------------------------------------
 sub SUM {
     my $mask=mask(@_);
     my $sum=0;
-    map {
+    foreach (grep /$mask/,keys(%v)) {
         $sum+=$v{$_};
-    } grep /$mask/,keys %v;
+    }
     return $sum;   
 }
 
+#-------------------------------------------------------
+
+=item MEAN(range)
+
+compute the average of the items in the range.
+
+=cut
+
+#-------------------------------------------------------
 sub MEAN {
     my $mask=mask(@_);
     my $sum=0; my $num=0;
-    map {
+    foreach (grep /$mask/,keys(%v)) {
         $sum+=$v{$_};
         $num++;
-    } grep /$mask/,keys %v;
+    }
     if ($num) {
        return $sum/$num;
     } else {
@@ -221,58 +590,104 @@ sub MEAN {
     }   
 }
 
+#-------------------------------------------------------
+
+=item STDDEV(range)
+
+compute the standard deviation of the items in the range.
+
+=cut
+
+#-------------------------------------------------------
 sub STDDEV {
     my $mask=mask(@_);
     my $sum=0; my $num=0;
-    map {
+    foreach (grep /$mask/,keys(%v)) {
         $sum+=$v{$_};
         $num++;
-    } grep /$mask/,keys %v;
+    }
     unless ($num>1) { return undef; }
     my $mean=$sum/$num;
     $sum=0;
-    map {
+    foreach (grep /$mask/,keys(%v)) {
         $sum+=($v{$_}-$mean)**2;
-    } grep /$mask/,keys %v;
+    }
     return sqrt($sum/($num-1));    
 }
 
+#-------------------------------------------------------
+
+=item PROD(range)
+
+compute the product of the items in the range.
+
+=cut
+
+#-------------------------------------------------------
 sub PROD {
     my $mask=mask(@_);
     my $prod=1;
-    map {
+    foreach (grep /$mask/,keys(%v)) {
         $prod*=$v{$_};
-    } grep /$mask/,keys %v;
+    }
     return $prod;   
 }
 
+#-------------------------------------------------------
+
+=item MAX(range)
+
+compute the maximum of the items in the range.
+
+=cut
+
+#-------------------------------------------------------
 sub MAX {
     my $mask=mask(@_);
     my $max='-';
-    map {
+    foreach (grep /$mask/,keys(%v)) {
         unless ($max) { $max=$v{$_}; }
         if (($v{$_}>$max) || ($max eq '-')) { $max=$v{$_}; }
-    } grep /$mask/,keys %v;
+    } 
     return $max;   
 }
 
+#-------------------------------------------------------
+
+=item MIN(range)
+
+compute the minimum of the items in the range.
+
+=cut
+
+#-------------------------------------------------------
 sub MIN {
     my $mask=mask(@_);
     my $min='-';
-    map {
+    foreach (grep /$mask/,keys(%v)) {
         unless ($max) { $max=$v{$_}; }
         if (($v{$_}<$min) || ($min eq '-')) { $min=$v{$_}; }
-    } grep /$mask/,keys %v;
+    }
     return $min;   
 }
 
+#-------------------------------------------------------
+
+=item SUMMAX(num,lower,upper)
+
+compute the sum of the largest 'num' items in the range from
+'lower' to 'upper'
+
+=cut
+
+#-------------------------------------------------------
 sub SUMMAX {
     my ($num,$lower,$upper)=@_;
     my $mask=mask($lower,$upper);
     my @inside=();
-    map {
-	$inside[$#inside+1]=$v{$_};
-    } grep /$mask/,keys %v;
+    foreach (grep /$mask/,keys(%v)) {
+	push (@inside,$v{$_});
+    }
     @inside=sort(@inside);
     my $sum=0; my $i;
     for ($i=$#inside;(($i>$#inside-$num) && ($i>=0));$i--) { 
@@ -281,13 +696,23 @@ sub SUMMAX {
     return $sum;   
 }
 
+#-------------------------------------------------------
+
+=item SUMMIN(num,lower,upper)
+
+compute the sum of the smallest 'num' items in the range from
+'lower' to 'upper'
+
+=cut
+
+#-------------------------------------------------------
 sub SUMMIN {
     my ($num,$lower,$upper)=@_;
     my $mask=mask($lower,$upper);
     my @inside=();
-    map {
+    foreach (grep /$mask/,keys(%v)) {
 	$inside[$#inside+1]=$v{$_};
-    } grep /$mask/,keys %v;
+    }
     @inside=sort(@inside);
     my $sum=0; my $i;
     for ($i=0;(($i<$num) && ($i<=$#inside));$i++) { 
@@ -296,6 +721,115 @@ sub SUMMIN {
     return $sum;   
 }
 
+#-------------------------------------------------------
+
+=item MINPARM(parametername)
+
+Returns the minimum value of the parameters matching the parametername.
+parametername should be a string such as 'duedate'.
+
+=cut
+
+#-------------------------------------------------------
+sub MINPARM {
+    my ($expression) = @_;
+    my $min = undef;
+    study($expression);
+    foreach $parameter (keys(%c)) {
+        next if ($parameter !~ /$expression/);
+        if ((! defined($min)) || ($min > $c{$parameter})) {
+            $min = $c{$parameter} 
+        }
+    }
+    return $min;
+}
+
+#-------------------------------------------------------
+
+=item MAXPARM(parametername)
+
+Returns the maximum value of the parameters matching the input parameter name.
+parametername should be a string such as 'duedate'.
+
+=cut
+
+#-------------------------------------------------------
+sub MAXPARM {
+    my ($expression) = @_;
+    my $max = undef;
+    study($expression);
+    foreach $parameter (keys(%c)) {
+        next if ($parameter !~ /$expression/);
+        if ((! defined($min)) || ($max < $c{$parameter})) {
+            $max = $c{$parameter} 
+        }
+    }
+    return $max;
+}
+
+#--------------------------------------------------------
+sub expandnamed {
+    my $expression=shift;
+    if ($expression=~/^\&/) {
+	my ($func,$var,$formula)=($expression=~/^\&(\w+)\(([^\;]+)\;(.*)\)/);
+	my @vars=split(/\W+/,$formula);
+        my %values=();
+        undef %values;
+	foreach ( @vars ) {
+            my $varname=$_;
+            if ($varname=~/\D/) {
+               $formula=~s/$varname/'$c{\''.$varname.'\'}'/ge;
+               $varname=~s/$var/\(\\w\+\)/g;
+	       foreach (keys(%c)) {
+		  if ($_=~/$varname/) {
+		      $values{$1}=1;
+                  }
+               }
+	    }
+        }
+        if ($func eq 'EXPANDSUM') {
+            my $result='';
+	    foreach (keys(%values)) {
+                my $thissum=$formula;
+                $thissum=~s/$var/$_/g;
+                $result.=$thissum.'+';
+            } 
+            $result=~s/\+$//;
+            return $result;
+        } else {
+	    return 0;
+        }
+    } else {
+        # it is not a function, so it is a parameter name
+        # We should do the following:
+        #    1. Take the list of parameter names
+        #    2. look through the list for ones that match the parameter we want
+        #    3. If there are no collisions, return the one that matches
+        #    4. If there is a collision, return 'bad parameter name error'
+        my $returnvalue = '';
+        my @matches = ();
+        $#matches = -1;
+        study $expression;
+        foreach $parameter (keys(%c)) {
+            push @matches,$parameter if ($parameter =~ /$expression/);
+        }
+        if ($#matches == 0) {
+            $returnvalue = '$c{\''.$matches[0].'\'}';
+        } elsif ($#matches > 0) {
+            # more than one match.  Look for a concise one
+            $returnvalue =  "'non-unique parameter name : $expression'";
+            foreach (@matches) {
+                if (/^$expression$/) {
+                    $returnvalue = '$c{\''.$_.'\'}';
+                }
+            }
+        } else {
+            $returnvalue =  "'bad parameter name : $expression'";
+        }
+        return $returnvalue;
+    }
+}
+
 sub sett {
     %t=();
     my $pattern='';
@@ -304,29 +838,40 @@ sub sett {
     } else {
         $pattern='[A-Z]';
     }
-    map {
+
+# Deal with the template row
+    foreach (keys(%f)) {
 	if ($_=~/template\_(\w)/) {
 	  my $col=$1;
           unless ($col=~/^$pattern/) {
-            map {
+	    foreach (keys(%f)) {
 	      if ($_=~/A(\d+)/) {
 		my $trow=$1;
                 if ($trow) {
+                    # Get the name of this cell
 		    my $lb=$col.$trow;
+                    # Grab the template declaration
                     $t{$lb}=$f{'template_'.$col};
+                    # Replace '#' with the row number
                     $t{$lb}=~s/\#/$trow/g;
+                    # Replace '....' with ','
                     $t{$lb}=~s/\.\.+/\,/g;
+                    # Replace 'A0' with the value from 'A0'
                     $t{$lb}=~s/(^|[^\"\'])([A-Za-z]\d+)/$1\$v\{\'$2\'\}/g;
-                    $t{$lb}=~s/(^|[^\"\'])\[(\w+)\]/$1\$c\{\'$2\'\}/g;
+                    # Replace parameters
+                    $t{$lb}=~s/(^|[^\"\'])\[([^\]]+)\]/$1.&expandnamed($2)/ge;
                 }
 	      }
-            } keys %f;
+	    }
 	  }
       }
-    } keys %f;
-    map {
+    }
+
+# Deal with the normal cells
+    foreach (keys(%f)) {
 	if (($f{$_}) && ($_!~/template\_/)) {
-            if ($_=~/^$pattern/) {
+            my $matches=($_=~/^$pattern(\d+)/);
+            if  (($matches) && ($1)) {
 	        unless ($f{$_}=~/^\!/) {
 		    $t{$_}=$c{$_};
                 }
@@ -334,36 +879,54 @@ sub sett {
 	       $t{$_}=$f{$_};
                $t{$_}=~s/\.\.+/\,/g;
                $t{$_}=~s/(^|[^\"\'])([A-Za-z]\d+)/$1\$v\{\'$2\'\}/g;
-               $t{$_}=~s/(^|[^\"\'])\[([\w\.]+)\]/$1\$c\{\'$2\'\}/g;
+               $t{$_}=~s/(^|[^\"\'])\[([^\]]+)\]/$1.&expandnamed($2)/ge;
             }
         }
-    } keys %f;
+    }
+# For inserted lines, [B-Z] is also valid
+
+    unless ($sheettype eq 'assesscalc') {
+       foreach (keys(%f)) {
+	   if ($_=~/[B-Z](\d+)/) {
+	       if ($f{'A'.$1}=~/^[\~\-]/) {
+  	          $t{$_}=$f{$_};
+                  $t{$_}=~s/\.\.+/\,/g;
+                  $t{$_}=~s/(^|[^\"\'])([A-Za-z]\d+)/$1\$v\{\'$2\'\}/g;
+                  $t{$_}=~s/(^|[^\"\'])\[([^\]]+)\]/$1.&expandnamed($2)/ge;
+               }
+           }
+       }
+    }
+
+    # For some reason 'A0' gets special treatment...  This seems superfluous
+    # but I imagine it is here for a reason.
     $t{'A0'}=$f{'A0'};
     $t{'A0'}=~s/\.\.+/\,/g;
     $t{'A0'}=~s/(^|[^\"\'])([A-Za-z]\d+)/$1\$v\{\'$2\'\}/g;
-    $t{'A0'}=~s/(^|[^\"\'])\[([\w\.]+)\]/$1\$c\{\'$2\'\}/g;
+    $t{'A0'}=~s/(^|[^\"\'])\[([^\]]+)\]/$1.&expandnamed($2)/ge;
 }
 
 sub calc {
-    %v=();
+    undef %v;
     &sett();
     my $notfinished=1;
+    my $lastcalc='';
     my $depth=0;
     while ($notfinished) {
 	$notfinished=0;
-        map {
+        foreach (keys(%t)) {
             my $old=$v{$_};
-            $v{$_}=eval($t{$_});
+            $v{$_}=eval $t{$_};
 	    if ($@) {
-		%v=();
-                return $@;
+		undef %v;
+                return $_.': '.$@;
             }
-	    if ($v{$_} ne $old) { $notfinished=1; }
-        } keys %t;
+	    if ($v{$_} ne $old) { $notfinished=1; $lastcalc=$_; }
+        }
         $depth++;
         if ($depth>100) {
-	    %v=();
-            return 'Maximum calculation depth exceeded';
+	    undef %v;
+            return $lastcalc.': Maximum calculation depth exceeded';
         }
     }
     return '';
@@ -372,14 +935,14 @@ sub calc {
 sub templaterow {
     my @cols=();
     $cols[0]='<b><font size=+1>Template</font></b>';
-    map {
+    foreach ('A','B','C','D','E','F','G','H','I','J','K','L','M',
+	     'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
+	     'a','b','c','d','e','f','g','h','i','j','k','l','m',
+	     'n','o','p','q','r','s','t','u','v','w','x','y','z') {
         my $fm=$f{'template_'.$_};
         $fm=~s/[\'\"]/\&\#34;/g;
         $cols[$#cols+1]="'template_$_','$fm'".'___eq___'.$fm;
-    } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-       'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
-       'a','b','c','d','e','f','g','h','i','j','k','l','m',
-       'n','o','p','q','r','s','t','u','v','w','x','y','z');
+    }
     return @cols;
 }
 
@@ -387,18 +950,31 @@ sub outrowassess {
     my $n=shift;
     my @cols=();
     if ($n) {
-       $cols[0]=$rl{$f{'A'.$n}};
+       my ($usy,$ufn)=split(/\_\_\&\&\&\_\_/,$f{'A'.$n});
+      if ($rowlabel{$usy}) {
+       $cols[0]=$rowlabel{$usy}.'<br>'.
+                '<select name="sel_'.$n.'" onChange="changesheet('.$n.
+                ')"><option name="default">Default</option>';
+      } else { $cols[0]=''; }
+       foreach (@os) {
+           $cols[0].='<option name="'.$_.'"';
+            if ($ufn eq $_) {
+               $cols[0].=' selected';
+            }
+            $cols[0].='>'.$_.'</option>';
+       }
+       $cols[0].='</select>';
     } else {
        $cols[0]='<b><font size=+1>Export</font></b>';
     }
-    map {
+    foreach ('A','B','C','D','E','F','G','H','I','J','K','L','M',
+	     'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
+	     'a','b','c','d','e','f','g','h','i','j','k','l','m',
+	     'n','o','p','q','r','s','t','u','v','w','x','y','z') {
         my $fm=$f{$_.$n};
         $fm=~s/[\'\"]/\&\#34;/g;
-        $cols[$#cols+1]="'$_$n','$fm'".'___eq___'.$v{$_.$n};
-    } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-       'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
-       'a','b','c','d','e','f','g','h','i','j','k','l','m',
-       'n','o','p','q','r','s','t','u','v','w','x','y','z');
+        push(@cols,"'$_$n','$fm'".'___eq___'.$v{$_.$n});
+    }
     return @cols;
 }
 
@@ -406,27 +982,27 @@ sub outrow {
     my $n=shift;
     my @cols=();
     if ($n) {
-       $cols[0]=$rl{$f{'A'.$n}};
+       $cols[0]=$rowlabel{$f{'A'.$n}};
     } else {
        $cols[0]='<b><font size=+1>Export</font></b>';
     }
-    map {
+    foreach ('A','B','C','D','E','F','G','H','I','J','K','L','M',
+	     'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
+	     'a','b','c','d','e','f','g','h','i','j','k','l','m',
+	     'n','o','p','q','r','s','t','u','v','w','x','y','z') {
         my $fm=$f{$_.$n};
         $fm=~s/[\'\"]/\&\#34;/g;
         $cols[$#cols+1]="'$_$n','$fm'".'___eq___'.$v{$_.$n};
-    } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-       'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
-       'a','b','c','d','e','f','g','h','i','j','k','l','m',
-       'n','o','p','q','r','s','t','u','v','w','x','y','z');
+    }
     return @cols;
 }
 
 sub exportrowa {
     my @exportarray=();
-    map {
+    foreach ('A','B','C','D','E','F','G','H','I','J','K','L','M',
+	     'N','O','P','Q','R','S','T','U','V','W','X','Y','Z') {
 	$exportarray[$#exportarray+1]=$v{$_.'0'};
-    } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-       'N','O','P','Q','R','S','T','U','V','W','X','Y','Z');
+    } 
     return @exportarray;
 }
 
@@ -450,18 +1026,25 @@ sub setconstants {
     %{$safeeval->varglob('c')}=%c;
 }
 
+# --------------------------------------------- Set names of other spreadsheets
+
+sub setothersheets {
+    my ($safeeval,@os)=@_;
+    @{$safeeval->varglob('os')}=@os;
+}
+
 # ------------------------------------------------ Add or change formula values
 
 sub setrowlabels {
-    my ($safeeval,%rl)=@_;
-    %{$safeeval->varglob('rl')}=%rl;
+    my ($safeeval,%rowlabel)=@_;
+    %{$safeeval->varglob('rowlabel')}=%rowlabel;
 }
 
 # ------------------------------------------------------- Calculate spreadsheet
 
 sub calcsheet {
     my $safeeval=shift;
-    $safeeval->reval('&calc();');
+    return $safeeval->reval('&calc();');
 }
 
 # ------------------------------------------------------------------ Get values
@@ -478,6 +1061,13 @@ sub getformulas {
     return %{$safeeval->varglob('f')};
 }
 
+# ----------------------------------------------------- Get value of $f{'A'.$n}
+
+sub getfa {
+    my ($safeeval,$n)=@_;
+    return $safeeval->reval('$f{"A'.$n.'"}');
+}
+
 # -------------------------------------------------------------------- Get type
 
 sub gettype {
@@ -590,6 +1180,7 @@ sub exportdata {
     return $safeeval->reval('&exportrowa()');
 }
 
+
 # ========================================================== End of Spreadsheet
 # =============================================================================
 
@@ -602,44 +1193,41 @@ sub rown {
     my ($safeeval,$n)=@_;
     my $defaultbg;
     my $rowdata='';
+    my $dataflag=0;
     unless ($n eq '-') {
        $defaultbg=((($n-1)/5)==int(($n-1)/5))?'#E0E0':'#FFFF';
     } else {
        $defaultbg='#E0FF';
     }
-    if ((($n-1)/25)==int(($n-1)/25)) {
-        my $what='Student';
-        if (&gettype($safeeval) eq 'assesscalc') {
-	    $what='Item';
-	} elsif (&gettype($safeeval) eq 'studentcalc') {
-            $what='Assessment';
-        }
-	$rowdata.="</table>\n<br><table border=2>".
-        '<tr><td>&nbsp;<td>'.$what.'</td>';
-        map {
-           $rowdata.='<td>'.$_.'</td>';
-        } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-           'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
-           'a','b','c','d','e','f','g','h','i','j','k','l','m',
-           'n','o','p','q','r','s','t','u','v','w','x','y','z');
-        $rowdata.='</tr>';
+    unless ($ENV{'form.showcsv'}) {
+       $rowdata.="\n<tr><td><b><font size=+1>$n</font></b></td>";
+    } else {
+       $rowdata.="\n".'"'.$n.'"';
     }
-    $rowdata.="\n<tr><td><b><font size=+1>$n</font></b></td>";
     my $showf=0;
     my $proc;
-    my $maxred;
-    if (&gettype($safeeval) eq 'assesscalc') {
+    my $maxred=1;
+    my $sheettype=&gettype($safeeval);
+    if ($sheettype eq 'studentcalc') {
         $proc='&outrowassess';
-        $maxred=1;
+        $maxred=26;
     } else {
         $proc='&outrow';
+    }
+    if ($sheettype eq 'assesscalc') {
+        $maxred=1;
+    } else {
         $maxred=26;
     }
-    if ($n eq '-') { $proc='&templaterow'; $n=-1; }
-    map {
+    if (&getfa($safeeval,$n)=~/^[\~\-]/) { $maxred=1; }
+    if ($n eq '-') { $proc='&templaterow'; $n=-1; $dataflag=1; }
+    foreach ($safeeval->reval($proc.'('.$n.')')) {
        my $bgcolor=$defaultbg.((($showf-1)/5==int(($showf-1)/5))?'99':'DD');
        my ($fm,$vl)=split(/\_\_\_eq\_\_\_/,$_);
+       if ((($vl ne '') || ($vl eq '0')) &&
+           (($showf==1) || ($sheettype ne 'studentcalc'))) { $dataflag=1; }
        if ($showf==0) { $vl=$_; }
+      unless ($ENV{'form.showcsv'}) {
        if ($showf<=$maxred) { $bgcolor='#FFDDDD'; }
        if (($n==0) && ($showf<=26)) { $bgcolor='#CCCCFF'; } 
        if (($showf>$maxred) || ((!$n) && ($showf>0))) {
@@ -652,9 +1240,16 @@ sub rown {
        } else {
            $rowdata.='<td bgcolor='.$bgcolor.'>&nbsp;'.$vl.'&nbsp;</td>';
        }
+      } else {
+	  $rowdata.=',"'.$vl.'"';
+      }
        $showf++;
-    } $safeeval->reval($proc.'('.$n.')');
-    return $rowdata.'</tr>';
+    }  # End of foreach($safeval...)
+    if ($ENV{'form.showall'} || ($dataflag)) {
+       return $rowdata.($ENV{'form.showcsv'}?'':'</tr>');
+    } else {
+       return '';
+    }
 }
 
 # ------------------------------------------------------------- Print out sheet
@@ -674,35 +1269,116 @@ sub outsheet {
         $realm='Course';
     }
     my $maxyellow=52-$maxred;
-    my $tabledata=
+    my $tabledata;
+    unless ($ENV{'form.showcsv'}) {
+       $tabledata=
         '<table border=2><tr><th colspan=2 rowspan=2><font size=+2>'.
                   $realm.'</font></th>'.
                   '<td bgcolor=#FFDDDD colspan='.$maxred.
                   '><b><font size=+1>Import</font></b></td>'.
                   '<td colspan='.$maxyellow.
 		  '><b><font size=+1>Calculations</font></b></td></tr><tr>';
-    my $showf=0;
-    map {
-        $showf++;
-        if ($showf<=$maxred) { 
-           $tabledata.='<td bgcolor="#FFDDDD">'; 
-        } else {
-           $tabledata.='<td>';
-        }
-        $tabledata.="<b><font size=+1>$_</font></b></td>";
-    } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-       'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
-       'a','b','c','d','e','f','g','h','i','j','k','l','m',
-       'n','o','p','q','r','s','t','u','v','w','x','y','z');
-    $tabledata.='</tr>';
+       my $showf=0;
+       foreach ('A','B','C','D','E','F','G','H','I','J','K','L','M',
+                'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
+                'a','b','c','d','e','f','g','h','i','j','k','l','m',
+                'n','o','p','q','r','s','t','u','v','w','x','y','z') {
+           $showf++;
+           if ($showf<=$maxred) { 
+               $tabledata.='<td bgcolor="#FFDDDD">'; 
+           } else {
+               $tabledata.='<td>';
+           }
+           $tabledata.="<b><font size=+1>$_</font></b></td>";
+       }
+       $tabledata.='</tr>'.&rown($safeeval,'-').&rown($safeeval,0);
+   } else { $tabledata='<pre>'; }
+
+    $r->print($tabledata);
+
     my $row;
     my $maxrow=&getmaxrow($safeeval);
-    $tabledata.=&rown($safeeval,'-');
-    $r->print($tabledata);
-    for ($row=0;$row<=$maxrow;$row++) {
-        $r->print(&rown($safeeval,$row));
+
+    my @sortby=();
+    my @sortidx=();
+    for ($row=1;$row<=$maxrow;$row++) {
+       $sortby[$row-1]=$safeeval->reval('$f{"A'.$row.'"}');
+       $sortidx[$row-1]=$row-1;
+    }
+    @sortidx=sort { $sortby[$a] cmp $sortby[$b]; } @sortidx;
+        my $what='Student';
+        if (&gettype($safeeval) eq 'assesscalc') {
+	    $what='Item';
+	} elsif (&gettype($safeeval) eq 'studentcalc') {
+            $what='Assessment';
+        }
+
+    my $n=0;
+    for ($row=0;$row<$maxrow;$row++) {
+        my $thisrow=&rown($safeeval,$sortidx[$row]+1);
+        if ($thisrow) {
+            if (($n/25==int($n/25)) && (!$ENV{'form.showcsv'})) {
+                $r->print("</table>\n<br>\n");
+                $r->rflush();
+                $r->print('<table border=2><tr><td>&nbsp;<td>'.$what.'</td>');
+                $r->print('<td>'.join('</td><td>',
+                                      (split(//,'ABCDEFGHIJKLMNOPQRSTUVWXYZ'.
+                                            'abcdefghijklmnopqrstuvwxyz'))).
+                          "</td></tr>\n");
+            }
+            $n++;
+            $r->print($thisrow);
+        }
     }
-    $r->print('</table>');
+    $r->print($ENV{'form.showcsv'}?'</pre>':'</table>');
+}
+
+#
+# ----------------------------------------------- Read list of available sheets
+# 
+sub othersheets {
+    my ($safeeval,$stype)=@_;
+    #
+    my $cnum=&getcnum($safeeval);
+    my $cdom=&getcdom($safeeval);
+    my $chome=&getchome($safeeval);
+    #
+    my @alternatives=();
+    my %results=&Apache::lonnet::dump($stype.'_spreadsheets',$cdom,$cnum);
+    my ($tmp) = keys(%results);
+    unless ($tmp =~ /^(con_lost|error|no_such_host)/i) {
+        @alternatives = sort (keys(%results));
+    }
+    return @alternatives; 
+}
+
+
+#
+# -------------------------------------- Parse a spreadsheet
+# 
+sub parse_sheet {
+    # $sheetxml is a scalar reference or a scalar
+    my ($sheetxml) = @_;
+    if (! ref($sheetxml)) {
+        my $tmp = $sheetxml;
+        $sheetxml = \$tmp;
+    }
+    my %f;
+    my $parser=HTML::TokeParser->new($sheetxml);
+    my $token;
+    while ($token=$parser->get_token) {
+        if ($token->[0] eq 'S') {
+            if ($token->[1] eq 'field') {
+                $f{$token->[2]->{'col'}.$token->[2]->{'row'}}=
+                    $parser->get_text('/field');
+            }
+            if ($token->[1] eq 'template') {
+                $f{'template_'.$token->[2]->{'col'}}=
+                    $parser->get_text('/template');
+            }
+        }
+    }
+    return \%f;
 }
 
 #
@@ -716,17 +1392,22 @@ sub readsheet {
   my $cdom=&getcdom($safeeval);
   my $chome=&getchome($safeeval);
 
-# --------- There is no filename. Look for defaults in course and global, cache
-
-  unless($fn) {
+  if (! defined($fn)) {
+      # There is no filename. Look for defaults in course and global, cache
       unless ($fn=$defaultsheets{$cnum.'_'.$cdom.'_'.$stype}) {
-         $fn=&Apache::lonnet::reply('get:'.$cdom.':'.$cnum.
-                                    ':environment:spreadsheet_default_'.$stype,
-                                    $chome);
-         unless (($fn) && ($fn!~/^error\:/)) {
-	     $fn='default_'.$stype;
-         }
-         $defaultsheets{$cnum.'_'.$cdom.'_'.$stype}=$fn; 
+          my %tmphash = &Apache::lonnet::get('environment',
+                                             ['spreadsheet_default_'.$stype],
+                                             $cdom,$cnum);
+          my ($tmp) = keys(%tmphash);
+          if ($tmp =~ /^(con_lost|error|no_such_host)/i) {
+              $fn = 'default_'.$stype;
+          } else {
+              $fn = $tmphash{'spreadsheet_default_'.$stype};
+          } 
+          unless (($fn) && ($fn!~/^error\:/)) {
+ 	     $fn='default_'.$stype;
+          }
+          $defaultsheets{$cnum.'_'.$cdom.'_'.$stype}=$fn; 
       }
   }
 
@@ -745,41 +1426,34 @@ sub readsheet {
      my %f=();
 
      if ($fn=~/^default\_/) {
-	my $sheetxml='';
-       {
+         my $sheetxml='';
          my $fh;
-         if ($fh=Apache::File->new($includedir.
-                         '/default.'.&gettype($safeeval))) {
-               $sheetxml=join('',<$fh>);
-          }
-       }
-        my $parser=HTML::TokeParser->new(\$sheetxml);
-        my $token;
-        while ($token=$parser->get_token) {
-          if ($token->[0] eq 'S') {
- 	     if ($token->[1] eq 'field') {
- 		 $f{$token->[2]->{'col'}.$token->[2]->{'row'}}=
- 		     $parser->get_text('/field');
- 	     }
-             if ($token->[1] eq 'template') {
-                 $f{'template_'.$token->[2]->{'col'}}=
-                     $parser->get_text('/template');
+         my $dfn=$fn;
+         $dfn=~s/\_/\./g;
+         if ($fh=Apache::File->new($includedir.'/'.$dfn)) {
+             $sheetxml=join('',<$fh>);
+         } else {
+             $sheetxml='<field row="0" col="A">"Error"</field>';
+         }
+         %f=%{&parse_sheet(\$sheetxml)};
+     } elsif($fn=~/\/*\.spreadsheet$/) {
+         my $sheetxml=&Apache::lonnet::getfile
+             (&Apache::lonnet::filelocation('',$fn));
+         if ($sheetxml == -1) {
+             $sheetxml='<field row="0" col="A">"Error loading spreadsheet '
+                 .$fn.'"</field>';
+         }
+         %f=%{&parse_sheet(\$sheetxml)};
+     } else {
+         my $sheet='';
+         my %tmphash = &Apache::lonnet::dump($fn,$cdom,$cnum);
+         my ($tmp) = keys(%tmphash);
+         unless ($tmp =~ /^(con_lost|error|no_such_host)/i) {
+             foreach (keys(%tmphash)) {
+                 $f{$_}=$tmphash{$_};
              }
-          }
-        }
-      } else {
-          my $sheet='';
-          my $reply=&Apache::lonnet::reply('dump:'.$cdom.':'.$cnum.':'.$fn,
-                                         $chome);
-          unless ($reply=~/^error\:/) {
-             $sheet=$reply;
-	  }
-          map {
-             my ($name,$value)=split(/\=/,$_);
-             $f{&Apache::lonnet::unescape($name)}=
-	        &Apache::lonnet::unescape($value);
-          } split(/\&/,$sheet);
-       }
+         }
+     }
 # --------------------------------------------------------------- Cache and set
        $spreadsheets{$cnum.'_'.$cdom.'_'.$stype.'_'.$fn}=join('___;___',%f);  
        &setformulas($safeeval,%f);
@@ -824,17 +1498,20 @@ sub writesheet {
     $spreadsheets{$cnum.'_'.$cdom.'_'.$stype.'_'.$fn}=join('___;___',%f);    
 # ----------------------------------------------------------------- Write sheet
     my $sheetdata='';
-    map {
+    foreach (keys(%f)) {
+     unless ($f{$_} eq 'import') {
        $sheetdata.=&Apache::lonnet::escape($_).'='.
 	   &Apache::lonnet::escape($f{$_}).'&';
-    } keys %f;
+     }
+    }
     $sheetdata=~s/\&$//;
     my $reply=&Apache::lonnet::reply('put:'.$cdom.':'.$cnum.':'.$fn.':'.
               $sheetdata,$chome);
     if ($reply eq 'ok') {
           $reply=&Apache::lonnet::reply('put:'.$cdom.':'.$cnum.':'.
               $stype.'_spreadsheets:'.
-              &Apache::lonnet::escape($fn).'='.$ENV{'user.name'},
+              &Apache::lonnet::escape($fn).'='.$ENV{'user.name'}.'@'.
+                                               $ENV{'user.domain'},
               $chome);
           if ($reply eq 'ok') {
               if ($makedef) { 
@@ -883,6 +1560,7 @@ sub tmpread {
     $fn=$tmpdir.$fn.'.tmp';
     my $fh;
     my %fo=();
+    my $countrows=0;
     if ($fh=Apache::File->new($fn)) {
         my $name;
         while ($name=<$fh>) {
@@ -890,9 +1568,29 @@ sub tmpread {
             my $value=<$fh>;
             chomp($value);
             $fo{$name}=$value;
+            if ($name=~/^A(\d+)$/) {
+		if ($1>$countrows) {
+		    $countrows=$1;
+                }
+            }
         }
     }
-    if ($nfield) { $fo{$nfield}=$nform; }
+    if ($nform eq 'changesheet') {
+        $fo{'A'.$nfield}=(split(/\_\_\&\&\&\_\_/,$fo{'A'.$nfield}))[0];
+        unless ($ENV{'form.sel_'.$nfield} eq 'Default') {
+	    $fo{'A'.$nfield}.='__&&&__'.$ENV{'form.sel_'.$nfield};
+        }
+    } elsif ($nfield eq 'insertrow') {
+        $countrows++;
+        my $newrow=substr('000000'.$countrows,-7);
+        if ($nform eq 'top') {
+	    $fo{'A'.$countrows}='--- '.$newrow;
+        } else {
+            $fo{'A'.$countrows}='~~~ '.$newrow;
+        }
+    } else {
+       if ($nfield) { $fo{$nfield}=$nform; }
+    }
     &setformulas($safeeval,%fo);
 }
 
@@ -920,7 +1618,7 @@ sub parmval {
 # ----------------------------------------------------- Cascading lookup scheme
        my $rwhat=$what;
        $what=~s/^parameter\_//;
-       $what=~s/\_/\./;
+       $what=~s/\_([^\_]+)$/\.$1/;
 
        my $symbparm=$symb.'.'.$what;
        my $mapparm=$mapname.'___(all).'.$what;
@@ -992,79 +1690,101 @@ sub updateclasssheet {
     my $cdom=&getcdom($safeeval);
     my $cid=&getcid($safeeval);
     my $chome=&getchome($safeeval);
-
-# ---------------------------------------------- Read class list and row labels
-
-    my $classlst=&Apache::lonnet::reply
-                                 ('dump:'.$cdom.':'.$cnum.':classlist',$chome);
+    #
+    # Read class list and row labels
+    my %classlist;
+    my @tmp = &Apache::lonnet::dump('classlist',$cdom,$cnum);
+    if ($tmp[0] !~ /^error/) {
+        %classlist = @tmp;
+    } else {
+        return 'Could not access course data';
+    }
+    undef @tmp;
+    #
     my %currentlist=();
     my $now=time;
-    unless ($classlst=~/^error\:/) {
-        map {
-            my ($name,$value)=split(/\=/,$_);
-            my ($end,$start)=split(/\:/,&Apache::lonnet::unescape($value));
-            my $active=1;
-            if (($end) && ($now>$end)) { $active=0; }
-            if ($active) {
-                my $rowlabel='';
-                $name=&Apache::lonnet::unescape($name);
-                my ($sname,$sdom)=split(/\:/,$name);
-                my $ssec=&Apache::lonnet::usection($sdom,$sname,$cid);
-                if ($ssec==-1) {
-                    $rowlabel='<font color=red>Data not available: '.$name.
-			      '</font>';
+    foreach my $student (keys(%classlist)) {
+        my ($end,$start)=split(/\:/,$classlist{$student});
+        my $active=1;
+        $active = 0 if (($end) && ($now>$end));
+        $active = 1 if ($ENV{'form.Status'} eq 'Any');
+        $active = !$active if ($ENV{'form.Status'} eq 'Expired');
+        if ($active) {
+            my $rowlabel='';
+            my ($studentName,$studentDomain)=split(/\:/,$student);
+            my $studentSection=&Apache::lonnet::usection($studentDomain,
+                                                         $studentName,$cid);
+            if ($studentSection==-1) {
+                unless ($ENV{'form.showcsv'}) {
+                    $rowlabel='<font color=red>Data not available: '.
+                        $studentName.'</font>';
                 } else {
-                    my %reply=&Apache::lonnet::idrget($sdom,$sname);
-                    my $reply=&Apache::lonnet::reply('get:'.$sdom.':'.$sname.
-		      ':environment:firstname&middlename&lastname&generation',
-                      &Apache::lonnet::homeserver($sname,$sdom));
-                    $rowlabel=$ssec.'&nbsp;'.$reply{$sname}.'<br>';
-                    map {
-                        $rowlabel.=&Apache::lonnet::unescape($_).' ';
-                    } split(/\&/,$reply);
+                    $rowlabel='ERROR","'.$studentName.
+                        '","Data not available","","","';
                 }
-		$currentlist{&Apache::lonnet::unescape($name)}=$rowlabel;
-            }
-        } split(/\&/,$classlst);
-#
-# -------------------- Find discrepancies between the course row table and this
-#
-        my %f=&getformulas($safeeval);
-        my $changed=0;
-
-        my $maxrow=0;
-        my %existing=();
-
-# ----------------------------------------------------------- Now obsolete rows
-	map {
-	    if ($_=~/^A(\d+)/) {
-                $maxrow=($1>$maxrow)?$1:$maxrow;
-                $existing{$f{$_}}=1;
-		unless ((defined($currentlist{$f{$_}})) || (!$1)) {
-		   $f{$_}='!!! Obsolete';
-                   $changed=1;
+            } else {
+                my %reply=&Apache::lonnet::idrget($studentDomain,$studentName);
+                my %studentInformation=&Apache::lonnet::get
+                    ('environment',
+                     ['lastname','generation','firstname','middlename','id'],
+                     $studentDomain,$studentName);
+                if (! $ENV{'form.showcsv'}) {
+                    $rowlabel='<a href="/adm/studentcalc?uname='.$studentName.
+                        '&udom='.$studentDomain.'">'.
+                            $studentSection.'&nbsp;';
+                    foreach ('id','firstname','middlename',
+                             'lastname','generation'){
+                        $rowlabel.=$studentInformation{$_}."&nbsp;";
+                    }
+                    $rowlabel.='</a>';
+                } else {
+                    $rowlabel= '"'.join('","',
+                                        ($studentSection,
+                                         $studentInformation{'id'},
+                                         $studentInformation{'firstname'},
+                                         $studentInformation{'middlename'},
+                                         $studentInformation{'lastname'},
+                                         $studentInformation{'generation'})
+                                        ).'"';
                 }
             }
-        } keys %f;
-
-# -------------------------------------------------------- New and unknown keys
-     
-        map {
-            unless ($existing{$_}) {
-		$changed=1;
-                $maxrow++;
-                $f{'A'.$maxrow}=$_;
+            $currentlist{$student}=$rowlabel;
+        } # end of if ($active)
+    } # end of foreach my $student (keys(%classlist))
+    #
+    # Find discrepancies between the course row table and this
+    #
+    my %f=&getformulas($safeeval);
+    my $changed=0;
+    #
+    my $maxrow=0;
+    my %existing=();
+    #
+    # Now obsolete rows
+    foreach (keys(%f)) {
+        if ($_=~/^A(\d+)/) {
+            $maxrow=($1>$maxrow)?$1:$maxrow;
+            $existing{$f{$_}}=1;
+            unless ((defined($currentlist{$f{$_}})) || (!$1) ||
+                    ($f{$_}=~/^(\~\~\~|\-\-\-)/)) {
+                $f{$_}='!!! Obsolete';
+                $changed=1;
             }
-        } sort keys %currentlist;        
-     
-        if ($changed) { &setformulas($safeeval,%f); }
-
-        &setmaxrow($safeeval,$maxrow);
-        &setrowlabels($safeeval,%currentlist);
-
-    } else {
-        return 'Could not access course data';
+        }
     }
+    #
+    # New and unknown keys
+    foreach (sort keys(%currentlist)) {
+        unless ($existing{$_}) {
+            $changed=1;
+            $maxrow++;
+            $f{'A'.$maxrow}=$_;
+        }
+    }
+    if ($changed) { &setformulas($safeeval,%f); }
+    #
+    &setmaxrow($safeeval,$maxrow);
+    &setrowlabels($safeeval,%currentlist);
 }
 
 # ----------------------------------- Update rows for student and assess sheets
@@ -1077,13 +1797,40 @@ sub updatestudentassesssheet {
     unless ($updatedata{$ENV{'request.course.fn'}.'_'.$stype}) {
 # -------------------------------------------------------------------- Tie hash
       if (tie(%bighash,'GDBM_File',$ENV{'request.course.fn'}.'.db',
-                       &GDBM_READER,0640)) {
+                       &GDBM_READER(),0640)) {
 # --------------------------------------------------------- Get all assessments
 
-	my %allkeys=();
-        my %allassess=();
+	my %allkeys=('timestamp' => 
+                     'Timestamp of Last Transaction<br>timestamp',
+                     'subnumber' =>
+                     'Number of Submissions<br>subnumber',
+                     'tutornumber' =>
+                     'Number of Tutor Responses<br>tutornumber',
+                     'totalpoints' =>
+                     'Total Points Granted<br>totalpoints');
+
+        my $adduserstr='';
+        if ((&getuname($safeeval) ne $ENV{'user.name'}) ||
+            (&getudom($safeeval) ne $ENV{'user.domain'})) {
+            $adduserstr='&uname='.&getuname($safeeval).
+		'&udom='.&getudom($safeeval);
+        }
+
+        my %allassess=('_feedback' =>
+	              '<a href="/adm/assesscalc?usymb=_feedback'.$adduserstr.
+                       '">Feedback</a>',
+                       '_evaluation' =>
+	              '<a href="/adm/assesscalc?usymb=_evaluation'.$adduserstr.
+                       '">Evaluation</a>',
+                       '_tutoring' =>
+	              '<a href="/adm/assesscalc?usymb=_tutoring'.$adduserstr.
+                       '">Tutoring</a>',
+                       '_discussion' =>
+	              '<a href="/adm/assesscalc?usymb=_discussion'.$adduserstr.
+                       '">Discussion</a>'
+        );
 
-        map {
+        foreach (keys(%bighash)) {
 	    if ($_=~/^src\_(\d+)\.(\d+)$/) {
 	       my $mapid=$1;
                my $resid=$2;
@@ -1095,9 +1842,11 @@ sub updatestudentassesssheet {
 			    '___'.$resid.'___'.
 			    &Apache::lonnet::declutter($srcf);
 		 $allassess{$symb}=
-    '<a href="/adm/assesscalc?usymb='.$symb.'">'.$bighash{'title_'.$id}.'</a>';
+	            '<a href="/adm/assesscalc?usymb='.$symb.$adduserstr.'">'.
+                     $bighash{'title_'.$id}.'</a>';
                  if ($stype eq 'assesscalc') {
-                   map {
+		     foreach (split(/\,/,
+				    &Apache::lonnet::metadata($srcf,'keys'))) {
                        if (($_=~/^stores\_(.*)/) || ($_=~/^parameter\_(.*)/)) {
 			  my $key=$_;
                           my $display=
@@ -1109,11 +1858,11 @@ sub updatestudentassesssheet {
                           $display.='<br>'.$key;
                           $allkeys{$key}=$display;
 		       }
-                   } split(/\,/,&Apache::lonnet::metadata($srcf,'keys'));
+                   } # end of foreach
 	         }
 	      }
 	   }
-        } keys %bighash;
+        } # end of foreach (keys(%bighash))
         untie(%bighash);
     
 #
@@ -1145,26 +1894,31 @@ sub updatestudentassesssheet {
         my %existing=();
 
 # ----------------------------------------------------------- Now obsolete rows
-	map {
+	foreach (keys(%f)) {
 	    if ($_=~/^A(\d+)/) {
                 $maxrow=($1>$maxrow)?$1:$maxrow;
-                $existing{$f{$_}}=1;
-		unless ((defined($current{$f{$_}})) || (!$1)) {
-		   $f{$_}='!!! Obsolete';
+                my ($usy,$ufn)=split(/\_\_\&\&\&\_\_/,$f{$_});
+                $existing{$usy}=1;
+		unless ((defined($current{$usy})) || (!$1) ||
+                        ($f{$_}=~/^(\~\~\~|\-\-\-)/)){
+ 		   $f{$_}='!!! Obsolete';
                    $changed=1;
+	        } elsif ($ufn) {
+		    $current{$usy}
+                       =~s/assesscalc\?usymb\=/assesscalc\?ufn\=$ufn\&usymb\=/;
                 }
             }
-        } keys %f;
+        }
 
 # -------------------------------------------------------- New and unknown keys
      
-        map {
+        foreach (keys(%current)) {
             unless ($existing{$_}) {
 		$changed=1;
                 $maxrow++;
                 $f{'A'.$maxrow}=$_;
             }
-        } keys %current;        
+        }
     
         if ($changed) { &setformulas($safeeval,%f); }
 
@@ -1182,30 +1936,28 @@ sub loadstudent {
     my %c=();
     my %f=&getformulas($safeeval);
     $cachedassess=&getuname($safeeval).':'.&getudom($safeeval);
-    %cachedstores=();
-    {
-      my $reply=&Apache::lonnet::reply('dump:'.&getudom($safeeval).':'.
-                                               &getuname($safeeval).':'.
-                                               &getcid($safeeval),
-                                               &getuhome($safeeval));
-      unless ($reply=~/^error\:/) {
-         map {
-            my ($name,$value)=split(/\=/,$_);
-            $cachedstores{&Apache::lonnet::unescape($name)}=
-	                  &Apache::lonnet::unescape($value);
-         } split(/\&/,$reply);
-      }
+    # Get ALL the student preformance data
+    my @tmp = &Apache::lonnet::dump(&getcid($safeeval),
+                                    &getudom($safeeval),
+                                    &getuname($safeeval),
+                                    undef);
+    if ($tmp[0] !~ /^error:/) {
+        %cachedstores = @tmp;
     }
+    undef @tmp;
+    # 
     my @assessdata=();
-    map {
+    foreach (keys(%f)) {
 	if ($_=~/^A(\d+)/) {
 	   my $row=$1;
-           unless ($f{$_}=~/^\!/) {
+           unless (($f{$_}=~/^[\!\~\-]/) || ($row==0)) {
+	      my ($usy,$ufn)=split(/__&&&\__/,$f{$_});
 	      @assessdata=&exportsheet(&getuname($safeeval),
                                        &getudom($safeeval),
-                                       'assesscalc',$f{$_});
+                                       'assesscalc',$usy,$ufn);
               my $index=0;
-              map {
+              foreach ('A','B','C','D','E','F','G','H','I','J','K','L','M',
+	               'N','O','P','Q','R','S','T','U','V','W','X','Y','Z') {
                   if ($assessdata[$index]) {
 		     my $col=$_;
 		     if ($assessdata[$index]=~/\D/) {
@@ -1218,11 +1970,10 @@ sub loadstudent {
                      }
 		  }
                   $index++;
-              } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-                 'N','O','P','Q','R','S','T','U','V','W','X','Y','Z');
+              }
 	   }
         }
-    } keys %f;
+    }
     $cachedassess='';
     undef %cachedstores;
     &setformulas($safeeval,%f);
@@ -1236,29 +1987,29 @@ sub loadcourse {
     my %c=();
     my %f=&getformulas($safeeval);
     my $total=0;
-    map {
+    foreach (keys(%f)) {
 	if ($_=~/^A(\d+)/) {
-	    unless ($f{$_}=~/^\!/) { $total++; }
+	    unless ($f{$_}=~/^[\!\~\-]/) { $total++; }
         }
-    } keys %f;
+    }
     my $now=0;
     my $since=time;
     $r->print(<<ENDPOP);
 <script>
     popwin=open('','popwin','width=400,height=100');
     popwin.document.writeln('<html><body bgcolor="#FFFFFF">'+
-      '<h1>Spreadsheet Calculation Progress</h1>'+
+      '<h3>Spreadsheet Calculation Progress</h3>'+
       '<form name=popremain>'+
       '<input type=text size=35 name=remaining value=Starting></form>'+
       '</body></html>');
-    popwin.document.close;
+    popwin.document.close();
 </script>
 ENDPOP
     $r->rflush();
-    map {
+    foreach (keys(%f)) {
 	if ($_=~/^A(\d+)/) {
 	   my $row=$1;
-           unless ($f{$_}=~/^\!/) {
+           unless (($f{$_}=~/^[\!\~\-]/)  || ($row==0)) {
 	      my @studentdata=&exportsheet(split(/\:/,$f{$_}),
                                            'studentcalc');
               undef %userrdatas;
@@ -1269,27 +2020,27 @@ ENDPOP
               $r->rflush(); 
 
               my $index=0;
-              map {
+              foreach ('A','B','C','D','E','F','G','H','I','J','K','L','M',
+                       'N','O','P','Q','R','S','T','U','V','W','X','Y','Z') {
                   if ($studentdata[$index]) {
-		     my $col=$_;
-		     if ($studentdata[$index]=~/\D/) {
-                         $c{$col.$row}="'".$studentdata[$index]."'";
- 		     } else {
-		         $c{$col.$row}=$studentdata[$index];
-		     }
-                     unless ($col eq 'A') { 
-			 $f{$col.$row}='import';
-                     }
+                      my $col=$_;
+                      if ($studentdata[$index]=~/\D/) {
+                          $c{$col.$row}="'".$studentdata[$index]."'";
+                      } else {
+                          $c{$col.$row}=$studentdata[$index];
+                      }
+                      unless ($col eq 'A') { 
+                          $f{$col.$row}='import';
+                      }
 		  }
                   $index++;
-              } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-                 'N','O','P','Q','R','S','T','U','V','W','X','Y','Z');
+              }
 	   }
         }
-    } keys %f;
+    }
     &setformulas($safeeval,%f);
     &setconstants($safeeval,%c);
-    $r->print('<script>popwin.close</script>');
+    $r->print('<script>popwin.close()</script>');
     $r->rflush(); 
 }
 
@@ -1322,9 +2073,9 @@ sub loadassessment {
        my $version=$cachedstores{'version:'.$symb};
        my $scope;
        for ($scope=1;$scope<=$version;$scope++) {
-           map {
+           foreach (split(/\:/,$cachedstores{$scope.':keys:'.$symb})) {
                $returnhash{$_}=$cachedstores{$scope.':'.$symb.':'.$_};
-           } split(/\:/,$cachedstores{$scope.':keys:'.$symb}); 
+           } 
        }
 
    } else {
@@ -1336,20 +2087,32 @@ sub loadassessment {
        "restore:$udom:$uname:".
        &Apache::lonnet::escape($namespace).":".
        &Apache::lonnet::escape($symb),$uhome);
-    map {
+    foreach (split(/\&/,$answer)) {
 	my ($name,$value)=split(/\=/,$_);
         $returnhash{&Apache::lonnet::unescape($name)}=
                     &Apache::lonnet::unescape($value);
-    } split(/\&/,$answer);
+    }
     my $version;
     for ($version=1;$version<=$returnhash{'version'};$version++) {
-       map {
+       foreach (split(/\:/,$returnhash{$version.':keys'})) {
           $returnhash{$_}=$returnhash{$version.':'.$_};
-       } split(/\:/,$returnhash{$version.':keys'});
+       } 
     }
    }
 # ----------------------------- returnhash now has all stores for this resource
 
+# --------- convert all "_" to "." to be able to use libraries, multiparts, etc
+
+    my @oldkeys=keys %returnhash;
+
+    foreach (@oldkeys) {
+        my $name=$_;
+        my $value=$returnhash{$_};
+        delete $returnhash{$_};
+        $name=~s/\_/\./g;
+        $returnhash{$name}=$value;
+    }
+
 # ---------------------------- initialize coursedata and userdata for this user
     undef %courseopt;
     undef %useropt;
@@ -1367,11 +2130,11 @@ sub loadassessment {
             $courserdatas{$cid.'.last_cache'}=time;
          }
       }
-      map {
+      foreach (split(/\&/,$courserdatas{$cid})) {
          my ($name,$value)=split(/\=/,$_);
          $courseopt{$userprefix.&Apache::lonnet::unescape($name)}=
                     &Apache::lonnet::unescape($value);  
-      } split(/\&/,$courserdatas{$cid});
+      }
 # --------------------------------------------------- Get userdata (if present)
       unless
         ((time-$userrdatas{$uname.'___'.$udom.'.last_cache'})<240) {
@@ -1382,38 +2145,52 @@ sub loadassessment {
 	     $userrdatas{$uname.'___'.$udom.'.last_cache'}=time;
          }
       }
-      map {
+      foreach (split(/\&/,$userrdatas{$uname.'___'.$udom})) {
          my ($name,$value)=split(/\=/,$_);
          $useropt{$userprefix.&Apache::lonnet::unescape($name)}=
 	          &Apache::lonnet::unescape($value);
-      } split(/\&/,$userrdatas{$uname.'___'.$udom});
+      }
     }
 # ----------------- now courseopt, useropt initialized for this user and course
 # (used by parmval)
 
+#
+# Load keys for this assessment only
+#
+    my %thisassess=();
+    my ($symap,$syid,$srcf)=split(/\_\_\_/,$symb);
+    
+    foreach (split(/\,/,&Apache::lonnet::metadata($srcf,'keys'))) {
+        $thisassess{$_}=1;
+    } 
+#
+# Load parameters
+#
    my %c=();
 
    if (tie(%parmhash,'GDBM_File',
-           &getcfn($safeeval).'_parms.db',&GDBM_READER,0640)) {
+           &getcfn($safeeval).'_parms.db',&GDBM_READER(),0640)) {
     my %f=&getformulas($safeeval);
-    map {
+    foreach (keys(%f))  {
 	if ($_=~/^A/) {
-            unless ($f{$_}=~/^\!/) {
+            unless ($f{$_}=~/^[\!\~\-]/) {
   	       if ($f{$_}=~/^parameter/) {
+		if ($thisassess{$f{$_}}) {
                   my $val=&parmval($f{$_},$safeeval);
                   $c{$_}=$val;
                   $c{$f{$_}}=$val;
+	        }
 	       } else {
 		  my $key=$f{$_};
                   my $ckey=$key;
                   $key=~s/^stores\_/resource\./;
-                  $key=~s/\_/\./;
+                  $key=~s/\_/\./g;
  	          $c{$_}=$returnhash{$key};
                   $c{$ckey}=$returnhash{$key};
 	       }
 	   }
         }
-    } keys %f;
+    }
     untie(%parmhash);
    }
    &setconstants($safeeval,%c);
@@ -1435,11 +2212,11 @@ sub hiddenfield {
 sub selectbox {
     my ($title,$name,$value,%options)=@_;
     my $selout="\n<p><b>$title:</b><br>".'<select name="'.$name.'">';
-    map {
+    foreach (sort keys(%options)) {
         $selout.='<option value="'.$_.'"';
         if ($_ eq $value) { $selout.=' selected'; }
         $selout.='>'.$options{$_}.'</option>';
-    } sort keys %options;
+    }
     return $selout.'</select>';
 }
 
@@ -1475,22 +2252,235 @@ sub loadrows {
     }
 }
 
+# ======================================================= Forced recalculation?
+
+sub checkthis {
+    my ($keyname,$time)=@_;
+    return ($time<$expiredates{$keyname});
+}
+sub forcedrecalc {
+    my ($uname,$udom,$stype,$usymb)=@_;
+    my $key=$uname.':'.$udom.':'.$stype.':'.$usymb;
+    my $time=$oldsheets{$key.'.time'};
+    if ($ENV{'form.forcerecalc'}) { return 1; }
+    unless ($time) { return 1; }
+    if ($stype eq 'assesscalc') {
+        my $map=(split(/\_\_\_/,$usymb))[0];
+        if (&checkthis('::assesscalc:',$time) ||
+            &checkthis('::assesscalc:'.$map,$time) ||
+            &checkthis('::assesscalc:'.$usymb,$time) ||
+            &checkthis($uname.':'.$udom.':assesscalc:',$time) ||
+            &checkthis($uname.':'.$udom.':assesscalc:'.$map,$time) ||
+            &checkthis($uname.':'.$udom.':assesscalc:'.$usymb,$time)) {
+            return 1;
+        } 
+    } else {
+        if (&checkthis('::studentcalc:',$time) || 
+            &checkthis($uname.':'.$udom.':studentcalc:',$time)) {
+	    return 1;
+        }
+    }
+    return 0; 
+}
+
 # ============================================================== Export handler
 #
 # Non-interactive call from with program
 #
 
 sub exportsheet {
+ my ($uname,$udom,$stype,$usymb,$fn)=@_;
+ my @exportarr=();
+
+ if (($usymb=~/^\_(\w+)/) && (!$fn)) {
+    $fn='default_'.$1;
+ }
+
+#
+# Check if cached
+#
+
+ my $key=$uname.':'.$udom.':'.$stype.':'.$usymb;
+ my $found='';
+
+ if ($oldsheets{$key}) {
+     foreach (split(/\_\_\_\&\_\_\_/,$oldsheets{$key})) {
+         my ($name,$value)=split(/\_\_\_\=\_\_\_/,$_);
+         if ($name eq $fn) {
+	     $found=$value;
+         }
+     }
+ }
+
+ unless ($found) {
+     &cachedssheets($uname,$udom,&Apache::lonnet::homeserver($uname,$udom));
+     if ($oldsheets{$key}) {
+	foreach (split(/\_\_\_\&\_\_\_/,$oldsheets{$key})) {
+            my ($name,$value)=split(/\_\_\_\=\_\_\_/,$_);
+            if ($name eq $fn) {
+	        $found=$value;
+            }
+        } 
+     }
+ }
+#
+# Check if still valid
+#
+ if ($found) {
+     if (&forcedrecalc($uname,$udom,$stype,$usymb)) {
+	 $found='';
+     }
+ }
  
-    my ($uname,$udom,$stype,$usymb,$fn)=@_;
+ if ($found) {
+#
+# Return what was cached
+#
+     @exportarr=split(/\_\_\_\;\_\_\_/,$found);
+
+ } else {
+#
+# Not cached
+#        
+
     my $thissheet=&makenewsheet($uname,$udom,$stype,$usymb);
     &readsheet($thissheet,$fn);
     &updatesheet($thissheet);
     &loadrows($thissheet);
-    &calcsheet($thissheet);
-    return &exportdata($thissheet);
+    &calcsheet($thissheet); 
+    @exportarr=&exportdata($thissheet);
+#
+# Store now
+#
+    my $cid=$ENV{'request.course.id'}; 
+    my $current='';
+    if ($stype eq 'studentcalc') {
+       $current=&Apache::lonnet::reply('get:'.
+                                     $ENV{'course.'.$cid.'.domain'}.':'.
+                                     $ENV{'course.'.$cid.'.num'}.
+				     ':nohist_calculatedsheets:'.
+                                     &Apache::lonnet::escape($key),
+                                     $ENV{'course.'.$cid.'.home'});
+    } else {
+       $current=&Apache::lonnet::reply('get:'.
+                                     &getudom($thissheet).':'.
+                                     &getuname($thissheet).
+				     ':nohist_calculatedsheets_'.
+                                     $ENV{'request.course.id'}.':'.
+                                     &Apache::lonnet::escape($key),
+                                     &getuhome($thissheet));
+
+    }
+    my %currentlystored=();
+    unless ($current=~/^error\:/) {
+       foreach (split(/\_\_\_\&\_\_\_/,&Apache::lonnet::unescape($current))) {
+           my ($name,$value)=split(/\_\_\_\=\_\_\_/,$_);
+           $currentlystored{$name}=$value;
+       }
+    }
+    $currentlystored{$fn}=join('___;___',@exportarr);
+
+    my $newstore='';
+    foreach (keys(%currentlystored)) {
+        if ($newstore) { $newstore.='___&___'; }
+        $newstore.=$_.'___=___'.$currentlystored{$_};
+    }
+    my $now=time;
+    if ($stype eq 'studentcalc') {
+       &Apache::lonnet::reply('put:'.
+                         $ENV{'course.'.$cid.'.domain'}.':'.
+                         $ENV{'course.'.$cid.'.num'}.
+			 ':nohist_calculatedsheets:'.
+                         &Apache::lonnet::escape($key).'='.
+			 &Apache::lonnet::escape($newstore).'&'.
+                         &Apache::lonnet::escape($key).'.time='.$now,
+                         $ENV{'course.'.$cid.'.home'});
+   } else {
+       &Apache::lonnet::reply('put:'.
+                         &getudom($thissheet).':'.
+                         &getuname($thissheet).
+			 ':nohist_calculatedsheets_'.
+                         $ENV{'request.course.id'}.':'.
+                         &Apache::lonnet::escape($key).'='.
+			 &Apache::lonnet::escape($newstore).'&'.
+                         &Apache::lonnet::escape($key).'.time='.$now,
+                         &getuhome($thissheet));
+   }
+ }
+ return @exportarr;
+}
+# ============================================================ Expiration Dates
+#
+# Load previously cached student spreadsheets for this course
+#
+
+sub expirationdates {
+    undef %expiredates;
+    my $cid=$ENV{'request.course.id'};
+    my $reply=&Apache::lonnet::reply('dump:'.
+				     $ENV{'course.'.$cid.'.domain'}.':'.
+                                     $ENV{'course.'.$cid.'.num'}.
+				     ':nohist_expirationdates',
+                                     $ENV{'course.'.$cid.'.home'});
+    unless ($reply=~/^error\:/) {
+	foreach (split(/\&/,$reply)) {
+            my ($name,$value)=split(/\=/,$_);
+            $expiredates{&Apache::lonnet::unescape($name)}
+                        =&Apache::lonnet::unescape($value);
+        }
+    }
+}
+
+# ===================================================== Calculated sheets cache
+#
+# Load previously cached student spreadsheets for this course
+#
+
+sub cachedcsheets {
+    my $cid=$ENV{'request.course.id'};
+    my $reply=&Apache::lonnet::reply('dump:'.
+				     $ENV{'course.'.$cid.'.domain'}.':'.
+                                     $ENV{'course.'.$cid.'.num'}.
+				     ':nohist_calculatedsheets',
+                                     $ENV{'course.'.$cid.'.home'});
+    unless ($reply=~/^error\:/) {
+	foreach ( split(/\&/,$reply)) {
+            my ($name,$value)=split(/\=/,$_);
+            $oldsheets{&Apache::lonnet::unescape($name)}
+                      =&Apache::lonnet::unescape($value);
+        }
+    }
+}
+
+# ===================================================== Calculated sheets cache
+#
+# Load previously cached assessment spreadsheets for this student
+#
+
+sub cachedssheets {
+  my ($sname,$sdom,$shome)=@_;
+  unless (($loadedcaches{$sname.'_'.$sdom}) || ($shome eq 'no_host')) {
+    my $cid=$ENV{'request.course.id'};
+    my $reply=&Apache::lonnet::reply('dump:'.$sdom.':'.$sname.
+			             ':nohist_calculatedsheets_'.
+                                      $ENV{'request.course.id'},
+                                     $shome);
+    unless ($reply=~/^error\:/) {
+	foreach ( split(/\&/,$reply)) {
+            my ($name,$value)=split(/\=/,$_);
+            $oldsheets{&Apache::lonnet::unescape($name)}
+                      =&Apache::lonnet::unescape($value);
+        }
+    }
+    $loadedcaches{$sname.'_'.$sdom}=1;
+  }
 }
 
+# ===================================================== Calculated sheets cache
+#
+# Load previously cached assessment spreadsheets for this student
+#
+
 # ================================================================ Main handler
 #
 # Interactive call to screen
@@ -1518,18 +2508,17 @@ $tmpdir=$r->dir_config('lonDaemons').'/t
 
 # --------------------------- Get query string for limited number of parameters
 
-    map {
-       my ($name, $value) = split(/=/,$_);
-       $value =~ tr/+/ /;
-       $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
-       if (($name eq 'uname') || ($name eq 'udom') || 
-           ($name eq 'usymb') || ($name eq 'ufn')) {
-           unless ($ENV{'form.'.$name}) {
-              $ENV{'form.'.$name}=$value;
-	   }
-       }
-    } (split(/&/,$ENV{'QUERY_STRING'}));
+    &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},
+                                            ['uname','udom','usymb','ufn']);
 
+    if (($ENV{'form.usymb'}=~/^\_(\w+)/) && (!$ENV{'form.ufn'})) {
+	$ENV{'form.ufn'}='default_'.$1;
+    }
+
+# -------------------------------------- Interactive loading of specific sheet?
+    if (($ENV{'form.load'}) && ($ENV{'form.loadthissheet'} ne 'Default')) {
+	$ENV{'form.ufn'}=$ENV{'form.loadthissheet'};
+    }
 # ------------------------------------------- Nothing there? Must be login user
 
     my $aname;
@@ -1558,18 +2547,28 @@ $tmpdir=$r->dir_config('lonDaemons').'/t
 
     function celledit(cn,cf) {
         var cnf=prompt(cn,cf);
-	if (cnf!=null) {
-	    document.sheet.unewfield.value=cn;
+        if (cnf!=null) {
+            document.sheet.unewfield.value=cn;
             document.sheet.unewformula.value=cnf;
             document.sheet.submit();
         }
     }
 
+    function changesheet(cn) {
+	document.sheet.unewfield.value=cn;
+        document.sheet.unewformula.value='changesheet';
+        document.sheet.submit();
+    }
+
+    function insertrow(cn) {
+	document.sheet.unewfield.value='insertrow';
+        document.sheet.unewformula.value=cn;
+        document.sheet.submit();
+    }
+
 </script>
 ENDSCRIPT
-    $r->print('</head><body bgcolor="#FFFFFF">'.
-       '<img align=right src=/adm/lonIcons/lonlogos.gif>'.
-       '<h1>LON-CAPA Spreadsheet</h1>'.
+   $r->print('</head>'.&Apache::loncommon::bodytag('Grades Spreadsheet').
        '<form action="'.$r->uri.'" name=sheet method=post>'.
        &hiddenfield('uname',$ENV{'form.uname'}).
        &hiddenfield('udom',$ENV{'form.udom'}).
@@ -1581,6 +2580,18 @@ ENDSCRIPT
 
     $r->rflush();
 
+# ---------------------------------------------------------------- Full recalc?
+
+
+    if ($ENV{'form.forcerecalc'}) {
+	$r->print('<h4>Completely Recalculating Sheet ...</h4>');
+        undef %spreadsheets;
+        undef %courserdatas;
+        undef %userrdatas;
+        undef %defaultsheets;
+        undef %updatedata;
+   }
+ 
 # ---------------------------------------- Read new sheet or modified worksheet
 
     $r->uri=~/\/(\w+)$/;
@@ -1616,34 +2627,42 @@ ENDSCRIPT
         } else {
            $r->print('<br><b>Section/Group:</b> '.&getcsec($asheet));
         }
+        if ($ENV{'form.usymb'}) {
+           $r->print('<br><b>Assessment:</b> <tt>'.$ENV{'form.usymb'}.'</tt>');
+        }
     }
 
-# ---------------------------------------------------------------- Course title
-
-    $r->print('<h1>'.
-            $ENV{'course.'.$ENV{'request.course.id'}.'.description'}.'</h1>');
-
-
-# ---------------------------------------------------- See if something to save
+# ---------------------------------------------------- See if user can see this
 
-    if (&Apache::lonnet::allowed('opa',$ENV{'request.course.id'})) {
-        my $fname='';
-	if ($ENV{'form.saveas'} && ($fname=$ENV{'form.newfn'})) {
-            $fname=~s/\W/\_/g;
-            if ($fname eq 'default') { $fname='course_default'; }
-            $fname.='_'.&gettype($asheet);
-            &setfilename($asheet,$fname);
-            $ENV{'form.ufn'}=$fname;
-	    $r->print('<p>Saving spreadsheet: '.
-                         &writesheet($asheet,$ENV{'form.makedefufn'}).'<p>');
-	}
+    if ((&gettype($asheet) eq 'classcalc') || 
+        (&getuname($asheet) ne $ENV{'user.name'}) ||
+        (&getudom($asheet) ne $ENV{'user.domain'})) {
+        unless (&Apache::lonnet::allowed('vgr',&getcid($asheet))) {
+	    $r->print(
+           '<h1>Access Permission Denied</h1></form></body></html>');
+            return OK;
+        }
     }
 
-# ------------------------------------------------ Write the modified worksheet
+# ---------------------------------------------------------- Additional options
 
-   $r->print('<b>Current sheet:</b> '.&getfilename($asheet).'<p>');
-
-   &tmpwrite($asheet);
+    $r->print(
+ '<input type=submit name=forcerecalc value="Completely Recalculate Sheet"><p>'
+		 );
+    if (&gettype($asheet) eq 'assesscalc') {
+       $r->print ('<p><font size=+2><a href="/adm/studentcalc?uname='.
+                                               &getuname($asheet).
+                                               '&udom='.&getudom($asheet).
+                  '">Level up: Student Sheet</a></font><p>');
+    }
+    
+    if ((&gettype($asheet) eq 'studentcalc') && 
+        (&Apache::lonnet::allowed('vgr',&getcid($asheet)))) {
+       $r->print (
+                   '<p><font size=+2><a href="/adm/classcalc">'.
+                   'Level up: Course Sheet</a></font><p>');
+    }
+    
 
 # ----------------------------------------------------------------- Save dialog
 
@@ -1659,10 +2678,45 @@ ENDSCRIPT
 
     $r->print(&hiddenfield('ufn',&getfilename($asheet)));
 
+# ----------------------------------------------------------------- Load dialog
+    if (&Apache::lonnet::allowed('opa',$ENV{'request.course.id'})) {
+	$r->print('<p><input type=submit name=load value="Load ...">'.
+                  '<select name="loadthissheet">'.
+                  '<option name="default">Default</option>');
+        foreach (&othersheets($asheet,&gettype($asheet))) {
+	    $r->print('<option name="'.$_.'"');
+            if ($ENV{'form.ufn'} eq $_) {
+               $r->print(' selected');
+            }
+            $r->print('>'.$_.'</option>');
+        } 
+        $r->print('</select><p>');
+        if (&gettype($asheet) eq 'studentcalc') {
+	    &setothersheets($asheet,&othersheets($asheet,'assesscalc'));
+        }
+    }
+
+# --------------------------------------------------------------- Cached sheets
+
+    &expirationdates();
+
+    undef %oldsheets;
+    undef %loadedcaches;
+
+    if (&gettype($asheet) eq 'classcalc') {
+        $r->print("Loading previously calculated student sheets ...<br>\n");
+        $r->rflush();
+        &cachedcsheets();
+    } elsif (&gettype($asheet) eq 'studentcalc') {
+        $r->print("Loading previously calculated assessment sheets ...<br>\n");
+        $r->rflush();
+        &cachedssheets(&getuname($asheet),&getudom($asheet),
+                       &getuhome($asheet));
+    }
 
 # ----------------------------------------------------- Update sheet, load rows
 
-    $r->print("Loaded sheet, updating rows ...<br>\n");
+    $r->print("Loaded sheet(s), updating rows ...<br>\n");
     $r->rflush();
 
     &updatesheet($asheet);
@@ -1678,6 +2732,71 @@ ENDSCRIPT
     my $calcoutput=&calcsheet($asheet);
     $r->print('<h3><font color=red>'.$calcoutput.'</h3></font>');
 
+# ---------------------------------------------------- See if something to save
+
+    if (&Apache::lonnet::allowed('opa',$ENV{'request.course.id'})) {
+        my $fname='';
+	if ($ENV{'form.saveas'} && ($fname=$ENV{'form.newfn'})) {
+            $fname=~s/\W/\_/g;
+            if ($fname eq 'default') { $fname='course_default'; }
+            $fname.='_'.&gettype($asheet);
+            &setfilename($asheet,$fname);
+            $ENV{'form.ufn'}=$fname;
+	    $r->print('<p>Saving spreadsheet: '.
+                         &writesheet($asheet,$ENV{'form.makedefufn'}).'<p>');
+	}
+    }
+
+# ------------------------------------------------ Write the modified worksheet
+
+   $r->print('<b>Current sheet:</b> '.&getfilename($asheet).'<p>');
+
+   &tmpwrite($asheet);
+
+    if (&gettype($asheet) eq 'studentcalc') {
+	$r->print('<br>Show rows with empty A column: ');
+    } else {
+        $r->print('<br>Show empty rows: ');
+    } 
+
+    $r->print(&hiddenfield('userselhidden','true').
+             '<input type=checkbox name=showall onClick="submit()"');
+
+    if ($ENV{'form.showall'}) { 
+       $r->print(' checked'); 
+    } else {
+	unless ($ENV{'form.userselhidden'}) {
+           unless 
+	($ENV{'course.'.$ENV{'request.course.id'}.'.hideemptyrows'} eq 'yes') {
+          $r->print(' checked');
+          $ENV{'form.showall'}=1;
+           }
+       }
+    }
+    $r->print('>');
+
+    if (&gettype($asheet) eq 'classcalc') {
+       $r->print(
+   ' Output CSV format: <input type=checkbox name=showcsv onClick="submit()"');
+       if ($ENV{'form.showcsv'}) { $r->print(' checked'); }
+       $r->print('>');
+    }
+
+# ------------------------------------------------------------------ Insertrows
+    $r->print('&nbsp;Student Status: '.
+              &Apache::lonhtmlcommon::StatusOptions
+              ($ENV{'form.Status'},'sheet'));
+
+   $r->print(<<ENDINSERTBUTTONS);
+<br>
+<input type='button' onClick='insertrow("top");' 
+value='Insert Row Top'>
+<input type='button' onClick='insertrow("bottom");' 
+value='Insert Row Bottom'><br>
+ENDINSERTBUTTONS
+
+# ------------------------------------------------------------- Print out sheet
+
     &outsheet($r,$asheet);
     $r->print('</form></body></html>');
 
@@ -1697,16 +2816,4 @@ __END__
 
 
 
-
-
-
-
-
-
-
-
-
-
-
-