Log Message:
-----------
Fixed a bug where if you specified a variable other than dx, the
division by zero check didn't work properly.
Modified Files:
--------------
pg/macros:
parserDifferenceQuotient.pl
Revision Data
-------------
Index: parserDifferenceQuotient.pl
===================================================================
RCS file: /webwork/cvs/system/pg/macros/parserDifferenceQuotient.pl,v
retrieving revision 1.2
retrieving revision 1.3
diff -Lmacros/parserDifferenceQuotient.pl -Lmacros/parserDifferenceQuotient.pl -u -r1.2 -r1.3
--- macros/parserDifferenceQuotient.pl
+++ macros/parserDifferenceQuotient.pl
@@ -52,10 +52,10 @@
$dx . '|' . $context->{_variables}->{pattern};
$context->update;
$context->variables->add($dx=>'Real');
- $dx = bless $self->SUPER::new($formula), $class;
- $dx->{isValue} = 1; $dx->{isFormula} = 1;
+ $q = bless $self->SUPER::new($formula), $class;
+ $q->{isValue} = 1; $q->{isFormula} = 1; $q->{dx} = $dx;
main::Context($current); # put back the original context;
- return $dx;
+ return $q;
}
sub cmp_class {'a Difference Quotient'}
@@ -66,10 +66,10 @@
)}
sub cmp_postprocess {
- my $self = shift; my $ans = shift;
+ my $self = shift; my $ans = shift; my $dx = $self->{dx};
return if $ans->{score} == 0 || $ans->{isPreview};
$main::__student_value__ = $ans->{student_value};
- my ($value,$err) = main::PG_restricted_eval('$__student_value__->reduce(dx=>0)');
+ my ($value,$err) = main::PG_restricted_eval('$__student_value__->substitute('.$dx.'=>0)->reduce');
$self->cmp_Error($ans,"It looks like you didn't finish simplifying your answer")
if $err && $err =~ m/division by zero/i;
}
|
