--- loncom/homework/functionplotresponse.pm	2011/09/28 23:33:52	1.64
+++ loncom/homework/functionplotresponse.pm	2011/10/13 01:54:12	1.65
@@ -1,7 +1,7 @@
 # LearningOnline Network with CAPA
 # option list style responses
 #
-# $Id: functionplotresponse.pm,v 1.64 2011/09/28 23:33:52 www Exp $
+# $Id: functionplotresponse.pm,v 1.65 2011/10/13 01:54:12 www Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -31,6 +31,7 @@ use strict;
 use Apache::response();
 use Apache::lonlocal;
 use Apache::lonnet;
+use Apache::run;
  
 BEGIN {
   &Apache::lonxml::register('Apache::functionplotresponse',('functionplotresponse','backgroundplot','spline',
@@ -563,7 +564,7 @@ sub start_functionplotrule {
                                    ['lt','less than'],
                                    ['le','less than or equal']],$token).
              $result.= &Apache::edit::select_or_text_arg('Value:','value',
-                                               [['undef','not defined']],$token,'8').
+                                               [['undef','not defined']],$token,'30').
              &Apache::edit::text_arg('Percent error:','percenterror',
                                      $token,'8').
              &Apache::edit::end_row();
@@ -979,15 +980,49 @@ sub actualval {
    my ($i,$xmin,$xmax)=@_;
    return $xmin+$i/400.*($xmax-$xmin);
 }
+
+sub fpr_f {
+   my ($arg)=@_;
+   return $Apache::functionplotresponse::func[&array_index($Apache::functionplotresponse::fpr_xmin,
+                                                           $Apache::functionplotresponse::fpr_xmax,
+                                                           $arg)];
+}
+
+sub fpr_dfdx {
+   my ($arg)=@_;
+   return $Apache::functionplotresponse::dfuncdx[&array_index($Apache::functionplotresponse::fpr_xmin,
+                                                              $Apache::functionplotresponse::fpr_xmax,
+                                                              $arg)];
+}
+
+sub fpr_d2fdx2 {
+   my ($arg)=@_;
+   return $Apache::functionplotresponse::d2funcdx2[&array_index($Apache::functionplotresponse::fpr_xmin,
+                                                                $Apache::functionplotresponse::fpr_xmax,
+                                                                $arg)];
+}
  
 sub functionplotrulecheck {
-   my ($rule,$xmin,$xmax,$ymin,$ymax)=@_;
+   my ($rule,$xmin,$xmax,$ymin,$ymax,$safeeval)=@_;
 
    my ($label,$derivative,$xinitial,$xinitiallabel,$xfinal,$xfinallabel,$minimumlength,$maximumlength,$relationship,$value,$percent)
       =split(/\:/,$rule);
    $percent=($percent>0?$percent:5);
    &addlog("=================");
    &addlog("Rule $label for ".($derivative<0?'integral':('function itself','first derivative','second derivative')[$derivative])." $relationship $value");
+#
+# Evaluate the value
+#
+   if ($value=~/\D/) {
+      $Apache::functionplotresponse::fpr_xmin=$xmin;
+      $Apache::functionplotresponse::fpr_xmax=$xmax;
+      $value=&Apache::run::run($value,$safeeval);
+      &addlog("Value evaluated to $value");
+   }
+
+#
+# Minimum and maximum lengths of the interval
+#
    if ((defined($minimumlength)) || (defined($maximumlength))) {
       &addlog("Minimumlength $minimumlength Maximumlength $maximumlength");
    }
@@ -1186,7 +1221,7 @@ sub end_functionplotruleset {
 
 # We have a function that we can actually grade, go through the spline rules.
            foreach my $rule (@Apache::functionplotresponse::functionplotrules) {
-              unless (&functionplotrulecheck($rule,$xmin,$xmax,$ymin,$ymax)) {
+              unless (&functionplotrulecheck($rule,$xmin,$xmax,$ymin,$ymax,$safeeval)) {
                  $ad='INCORRECT';
                  last;
               }