[LON-CAPA-users] restricting incorrect answers in exam mode
Gerd Kortemeyer
lon-capa-users@mail.lon-capa.org
Thu, 23 Mar 2006 20:37:49 -0500
Hi Nathan,
On Mar 23, 2006, at 6:15 PM, Felicia Berryman wrote:
>
>> I'd like to restrict the incorrect answers that LON-CAPA
>> generates for exam mode to a certain range, namely 0 to 1. Is
>> there a simple way to do this?
>
>
> There is not built-in method with LON-CAPA where you can specify a
> range for your wrong answers. See http://bugs.loncapa.org/
> show_bug.cgi?id=2702. You can however hard-code what answers
> appear for your wrong answers. Then you can specify the array of
> wrong answers in the incorrect answer location. There is also a
> parameter for number of bubbles. Make sure that the you specify at
> least number-of-bubbles - 1 wrong answers. The default is 8
> bubbles in exam mode.
I have provided a few routines in
/res/msu/kortemey/physicslib/wrong.library
You'll need to include this library in your problem.
Then you can call
@wrong=&wrongperc(0,1,0.01,$correct,10);
That will generate a "wrong" array with values between 0 and 1 in
steps of 0.01 that miss the value $correct by 10 percent.
@wrong=&wrongabs(3,15,0.5,$correct,0.5);
will generate wrong values between 3 and 15 missing $correct by
absolute 0.5
That wrong array needs to be put into the <numericalresponse>
incorrect location, as Felicia explains above.
If you want to include certain values, you can do
@wrong=(0,1,&wrongperc(0.01,0.99,0.01,$correct,10,5);
That way, you always have 0 and 1 as answers, as well as 5 additional
wrong answers between 0.01 and 0.99 in steps of 0.01, but missing
$correct by 10 percent.
- Gerd.