--- loncom/homework/default_homework.lcpm	2010/12/16 16:01:01	1.151
+++ loncom/homework/default_homework.lcpm	2011/06/08 01:39:28	1.157
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA 
 # used by lonxml::xmlparse() as input variable $safeinit to Apache::run::run()
 #
-# $Id: default_homework.lcpm,v 1.151 2010/12/16 16:01:01 raeburn Exp $
+# $Id: default_homework.lcpm,v 1.157 2011/06/08 01:39:28 www Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -270,7 +270,10 @@ sub caparesponse_check_list {
     my $type = $LONCAPA::CAPAresponse_args{'type'};
     my $answerunit=$LONCAPA::CAPAresponse_args{'unit'};
     &LONCAPA_INTERNAL_DEBUG("Got type :$type: answer unit :$answerunit:\n");
-    
+   
+    my $preprocess=$LONCAPA::CAPAresponse_args{'preprocess'};
+    $preprocess=~s/^\&//;
+
     my $num_input_lines =
 	scalar(@{$LONCAPA::CAPAresponse_answer->{'answers'}});
     
@@ -309,12 +312,19 @@ sub caparesponse_check_list {
 
     &LONCAPA_INTERNAL_DEBUG("Initial final response :$responses->[0][-1]:");
     my $unit;
+    my ($allowalgebra)=(&parameter_setting('allowalgebra',&currentpart())=~/^(yes|1|on)$/i);
     if ($type eq 'float' || $type eq '') {
 	#for numerical problems split off the unit
-#	if ( $responses->[0][-1]=~ /(.*[^\s])\s+([^\s]+)/ ) {
-        if ( $responses->[0][-1]=~ /^([\d\.\,\s\$]*(?:(?:[xX\*]10[\^\*]*|[eE]*)[\+\-]*\d*)*(?:^|\S)\d+)([\$\s\w\^\*\/\(\)\+\-]*[^\d\.\s\,][\$\s\w\^\*\/\(\)\+\-]*)$/ ) {
-	    $responses->[0][-1]=$1;
-	    $unit=&capa_formula_fix($2);
+        my $part1;
+        my $part2;
+        if ($allowalgebra) {
+           ($part1,$part2)=($responses->[0][-1]=~ /^(.*[^\s])\s+([^\s]+)$/); 
+        } else {
+           ($part1,$part2)=($responses->[0][-1]=~ /^([\d\.\,\s\$]*(?:(?:[xX\*]10[\^\*]*|[eE]*)[\+\-]*\d*)*(?:^|\S)\d+)([\$\s\w\^\*\/\(\)\+\-]*[^\d\.\s\,][\$\s\w\^\*\/\(\)\+\-]*)$/);
+        }
+        if (defined($part1) && defined($part2)) {
+	    $responses->[0][-1]=$part1;
+	    $unit=&capa_formula_fix($part2);
             &LONCAPA_INTERNAL_DEBUG("Found unit :$unit:");
 	}
     }
@@ -322,7 +332,15 @@ sub caparesponse_check_list {
     $unit=~s/\s//;
     my $error;
     foreach my $response (@$responses) {
-       foreach my $element (@$response) {	
+       foreach my $element (@$response) {
+          # See if we have preprocessor
+          if ($preprocess=~/\S/) {
+             if (defined(&$preprocess)) {
+                no strict 'refs';
+                $element=&$preprocess($element);
+                use strict 'refs';
+             }
+          }
           if (($type eq 'float') || (($type eq '') && ($unit ne ''))) {
               $element =~ s/\s//g;
           }
@@ -344,6 +362,10 @@ sub caparesponse_check_list {
           if (($element==0) && ($unit!~/\w/) && ($answerunit=~/\w/)) {
              $appendunit=$answerunit;
           }
+# Do the math for the student if allowed
+          if ($allowalgebra) {
+             $element=&cas('maxima',$element);
+          }
           if ($appendunit ne '') {
               $element .= " $appendunit";
           }  
@@ -364,6 +386,7 @@ sub caparesponse_check_list {
         if (ref($LONCAPA::CAPAresponse_answer->{'answers'}) eq 'ARRAY') {
             foreach my $strans (@{$LONCAPA::CAPAresponse_answer->{'answers'}}) {
                 if (ref($strans) eq 'ARRAY') {
+                    $ansstring = join("\0",@{$strans});
                     foreach my $item (@{$strans}) {  
                         if ($item =~ /[\000-\037]/) {
                             $allow_control_char = 1;
@@ -373,15 +396,6 @@ sub caparesponse_check_list {
             }
         }
     }
-    if (($type eq 'cs') || ($type eq 'ci')) {
-        if (ref($LONCAPA::CAPAresponse_answer->{'answers'}) eq 'ARRAY') {
-            foreach my $answer (@{ $LONCAPA::CAPAresponse_answer->{'answers'} }) {
-                if (ref($answer) eq 'ARRAY') {
-                    $ansstring = join("\0",@{$answer});
-                }
-            }
-        }
-    }
 
 #    &LONCAPA_INTERNAL_DEBUG(&LONCAPA_INTERNAL_Dumper($responses));
     my %memoized;
@@ -1133,11 +1147,24 @@ sub class {
     return $course;
 }
 
+sub classid {
+    my $courseid = &EXT('request.course.id');
+    $courseid = '' if $courseid eq "";
+    return $courseid;
+}
+
 sub firstname {
     my $firstname = &EXT('environment.firstname');
     $firstname = '' if $firstname eq "";
     return $firstname;
 }
+
+sub middlename {
+    my $middlename = &EXT('environment.middlename');
+    $middlename = '' if $middlename eq "";
+    return $middlename;
+}
+
                                                                                 
 sub lastname {
     my $lastname = &EXT('environment.lastname');
@@ -1204,6 +1231,40 @@ sub answer_date_epoch {
     return &EXT('resource.'.$partid.'.answerdate');
 }
 
+sub parameter_setting {
+    my ($which,$partid)=@_;
+    unless ($partid) { $partid=0; }
+    return &EXT('resource.'.$partid.'.'.$which);
+}
+
+sub stored_data {
+    my ($which,$partid)=@_;
+    unless ($partid) { $partid=0; }
+    return &EXT('user.resource.resource.'.$partid.'.'.$which);
+}
+
+sub wrong_bubbles {
+    my ($correct,$lower,$upper,$step,@given)=@_;
+    my @array=();
+    my %hash=();
+    foreach my $new (@given) {
+        $hash{$new}=1;
+    }
+    my $num=int(&parameter_setting('numbubbles',&currentpart()));
+    unless ($num) { $num=8; }
+    if ($num>1) {
+        for (my $i=0;$i<=500;$i++) {
+            my $new=&random($lower,$upper,$step);
+            if ($hash{$new}) { next; }
+            if (abs($new-$correct)<$step) { next; }
+            $hash{$new}=1;
+            @array=keys(%hash);
+            if ($#array+2>=$num) { last; }
+        }
+    }
+    return @array;
+}
+
 sub array_moments {
     my @input=@_;
     my (@output,$N);