--- loncom/homework/default_homework.lcpm	2014/06/16 16:52:50	1.164
+++ loncom/homework/default_homework.lcpm	2014/06/25 16:50:51	1.169
@@ -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 1.164 2014/06/16 16:52:50 bisitz Exp $
+# $Id: default_homework.lcpm,v 1.169 2014/06/25 16:50:51 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -1033,17 +1033,6 @@ sub format_significant_figures {
     $number = abs($number);
     # needed to correct for a number greater than 1 (or
     my $power = ($number < 1) ? 0 : 1;
-    if ($power && $number =~ /^\d+$/) {
-        my $nonzeros = $number;
-        $nonzeros =~ s/0+$//;
-        if (length($number) - length($nonzeros) > 1) {
-            # convert to exponential form
-            my $n = $sig-1;
-            my $numSig = sprintf('%.' . $n . 'E', $number);
-            # return number with sign
-            return $sign.$numSig;
-        }
-    }
     # could round up. Take the integer part of log10.
     my $x10 = int(log($number)/log(10));
     # find number with values left of decimal pt = # of sign figs.
@@ -1054,16 +1043,47 @@ sub format_significant_figures {
     my ($zeros) = ($xint =~ /(0+)$/);
     # return number to original magnitude
     my $numSig = $xint*10**($x10-$sig+$power);
-    # insert trailing zero's if have decimal point
-    $numSig =~ s/^(\d+)\.(\d+)(\e?(.*)?)$/$1\.$2$zeros$3/;
-    # put a decimal pt for number ending with 0 and length = # of sig fig
-    $numSig.='.' if (length($numSig) == $sig && $numSig =~ /0$/);
-    if (length($numSig) < $sig) {
-	$numSig.='.'.substr($zeros,0,($sig-length($numSig)));
+    if ($numSig =~ /^(\d+)\.(\d+)/) {
+        # insert trailing zero's if have decimal point
+        my @digarray = split('',$1.$2);
+        my $sigcount;
+        while (@digarray > 0) {
+            my $item = shift(@digarray);
+            if ($item) {
+                $sigcount = 1 + @digarray;
+                last;
+            }
+        }
+        if (($sigcount) && ($sig >= $sigcount)) {
+            $zeros = substr($zeros,0,($sig - $sigcount));
+        }
+        $numSig =~ s/^(\d+)\.(\d+)(\e?(.*)?)$/$1\.$2$zeros$3/;
+    } else {
+        if ($numSig =~ /^(\d+)e([\+\-]\d+)$/i) {
+            my $pre_exp = $1;
+            my $exponent = $2;
+            $numSig = $pre_exp.'.'.$zeros.'E'.$exponent;
+        } elsif ($numSig =~ /0$/) {
+            # add decimal pt for number ending with 0 and length == # of sig figs
+            if (length($numSig) == $sig) {
+                $numSig.='.';
+            } elsif (length($numSig) > $sig) {
+                # exponential form for number ending with 0 and length > # of sig figs
+                my $fmtsig = $sig-1;
+                if ($fmtsig) {
+                    $numSig = sprintf('%.'.$fmtsig.'E',$numSig);
+                }
+            } elsif (length($numSig) < $sig) {
+                $numSig.='.'.substr($zeros,0,($sig-length($numSig)));
+            }
+        } else {
+            if (length($numSig) < $sig) {
+                $numSig.='.'.substr($zeros,0,($sig-length($numSig)));
+            }
+        }
     }
     # return number with sign
     return $sign.$numSig;
-
 }
 
 sub map {
@@ -1208,18 +1228,78 @@ sub sec {
 }
 
 sub submission {
-   my ($partid,$responseid,$subnumber,$encode)=@_;
+   my ($partid,$responseid,$subnumber,$encode,$cleanupnum)=@_;
    my $sub='';
    if ($subnumber) { $sub=$subnumber.':'; }
    my $output =
        &EXT('user.resource.'.$sub.'resource.'.$partid.'.'.$responseid.'.submission');
-   if ($encode) {
-       $output =~ s/&/&amp;/g;
-       $output =~ s/</&lt;/g;
-       $output =~ s/>/&gt;/g;
-       $output =~ s/"/&quot;/g;
-   };
-   return $output;
+   if (ref($output) eq 'ARRAY') {
+       my @items = @{$output};
+       if ($encode) {
+           @items = map { &encode_response($_); } @items;
+       }
+       if (ref($cleanupnum) eq 'HASH') {
+           @items = map { &cleanup_numerical_response($cleanupnum,$_); } @items;
+       }
+       return \@items;
+   } else {
+       if ($encode) {
+           $output = &encode_response($output);
+       }
+       if (ref($cleanupnum) eq 'HASH') {
+           $output = &cleanup_numerical_response($cleanupnum,$output);
+       }
+       return $output;
+   }
+}
+
+sub encode_response {
+    my ($value) = @_;
+    $value =~ s/&/&amp;/g;
+    $value =~ s/</&lt;/g;
+    $value =~ s/>/&gt;/g;
+    $value =~ s/"/&quot;/g;
+    return $value;
+}
+
+sub cleanup_numerical_response {
+    my ($cleanupnum,$value) = @_;
+    if (ref($cleanupnum) eq 'HASH') {
+        if ($cleanupnum->{exponent}) {
+            if ($value =~ m{^(.*)[\*xX]\s*10\s*\^\s*(\+|\-)?\s*(\d+)(.*)$}) {
+                my $pre_exp = $1;
+                my $sign = $2;
+                my $exponent = $3;
+                my $post_exp = $4;
+                if ($pre_exp !~ /\./) {
+                    $pre_exp .= '.';
+                }
+                if ($sign eq '') {
+                    $sign = '+';
+                }
+                $value = $pre_exp.'E'.$sign.$exponent.$post_exp;
+            }
+        }
+        if ($cleanupnum->{comma}) {
+            $value =~ s{(\d+),(\d+)}{$1$2};
+        }
+        if ($cleanupnum->{letterforzero}) {
+            $value =~ s/^\s*o(\.\d+)/0$1/i;
+        }
+        if ($cleanupnum->{spaces}) {
+            $value =~ s{^\s+|\s+$}{}g;
+            if ($value =~ m{^(.*)\.\s+(\d+)(.*)$}) {
+                my $pre_pt = $1;
+                my $decimal = $2;
+                my $post_dec = $3;
+                $value = $pre_pt.'.'.$decimal.$post_dec;
+            }
+        }
+        if ($cleanupnum->{format} =~ /^\d+s$/i) {
+            $value = &format_significant_figures($value,$cleanupnum->{format});
+        }
+    }
+    return $value;
 }
 
 sub currentpart {