--- loncom/homework/default_homework.lcpm	2001/07/23 22:40:59	1.32
+++ loncom/homework/default_homework.lcpm	2001/10/05 22:28:31	1.38
@@ -7,27 +7,23 @@
 # 05/31/2001 H. K. Ng
 #
 #init some globals
-$RANDOMINIT=0;
+$hidden::RANDOMINIT=0;
 $pi=atan2(1,1)*4;
 $rad2deg=180.0/$pi;
 $deg2rad=$pi/180.0;
 
 sub caparesponse_check {
-  my $answer='';  #done
-  my $type='';    #done
+  #not properly used yet: calc
+  #not to be used: $ans_fmt
+  my ($answer,$type,$tol,$sig,$ans_fmt,$unit,$calc) = 
+	eval $_[1].';return ($answer,$type,$tol,$sig,$ans_fmt,$unit,$calc);';
+
   my $tol_type=''; # gets it's value from whether tol has a % or not done
-  my $tol='';     #done
-  my $sig='';     #done lowerbnd,upperbnd
   my $sig_lbound=''; #done
   my $sig_ubound=''; #done
-  my $ans_fmt='';
-  my $unit='';     #done
-  my $calc='';
   my ($response,$expr)=@_;
 
 
-  ($answer,$type,$tol,$sig,$ans_fmt,
-   $unit,$calc) = eval $expr.';return ($answer,$type,$tol,$sig,$ans_fmt,$unit,$calc);';
   #type's definitons come from capaParser.h
   my $message='';
   #remove leading and trailing whitespace
@@ -88,14 +84,14 @@ sub caparesponse_check {
   elsif ($result =='12') { $result='WANTED_NUMERIC'; }
   else  {$result = "ERROR: Unknown Result:$result:$@:";}
 
-  return "$result:<br />Error $error:<br />Answer $answer:<br />Response $response:<br /> type-$type|$tol|$tol_type|$sig:$sig_lbound:$sig_ubound|$units<br />$message$expr";
+  return "$result:<br />Error $error:<br />Answer $answer:<br />Response $response:<br /> type-$type|$tol|$tol_type|$sig:$sig_lbound:$sig_ubound|$unit|<br />$message$expr";
 }
 
-sub caparesponse_check_list {
-  my ($response,$expr)=@_;
+sub get_array_args {
+  my ($expr,$arg)=@_;
   # do these first, because who knows what varname the instructor might have used
   # but it probably isn't $CAPARESPONSE_CHECK_LIST_answer
-  my $CAPARESPONSE_CHECK_LIST_answer = eval $expr.';return $answer';
+  my $CAPARESPONSE_CHECK_LIST_answer = eval $expr.';return $'.$arg; #'
   my (@list) = eval $CAPARESPONSE_CHECK_LIST_answer;
   my $result='';
   $result.="error:$@:<br />";
@@ -104,6 +100,12 @@ sub caparesponse_check_list {
     $result.="list zero is undefined<br />";
     $list[0]=$CAPARESPONSE_CHECK_LIST_answer;
   }
+  return @list;
+}
+
+sub caparesponse_check_list {
+  my ($response,$expr)=@_;
+  my (@list) = &get_array_args($expr,'answer');
   my $aresult='';
   my $current_answer;
   $result.="Got response :$CAPARESPONSE_CHECK_LIST_answer:$list[0]:<br />";
@@ -189,7 +191,10 @@ sub hinton {
 
 sub random {
   my ($start,$end,$step)=@_;
-  if ( ! $RANDOMINIT ) { srand($external::randomseed); $RANDOMINIT=1; }
+  if ( ! $hidden::RANDOMINIT ) {
+    srand($external::randomseed);
+    $hidden::RANDOMINIT=1;
+  }
   my $num=1+int(($end-$start)/$step);
   my $result=$start + int(rand() * $num)*$step;
   return $result;
@@ -268,16 +273,9 @@ sub random_noncentral_f {
 }
 
 sub random_multivariate_normal {
-  my ($item_cnt,$seed,@mean) = @_;
-  return "Number of deviates must be greater than 0" if $item_cnt <= 0;
-  my (@covar,@retArray);
-  my $ind = 0;
-  while ($ind<$item_cnt) {
-     push @covar, pop (@mean);
-     $ind++;
-  }
+  my ($item_cnt,$seed,$mean,$covar) = @_;
   &random_set_seed_from_phrase($seed);
-  @retArray=&math_random_multivariate_normal($item_cnt,@mean,@covar);
+  @retArray=&math_random_multivariate_normal($item_cnt,@$mean,@$covar);
   return @retArray;
 }