Questionnaire: divide by zero warning

Set up a course which has multiple groups in it, at least one of which has no members.

Set up a questionnaire to use "visible groups", and log in as a student and complete a response.

Go to 'View all Responses' link

• the Visible groups drop down displaying as All participants

Select a group from the drop down ending in (0)

• group is changed and there are no results displaying on the page

Select the 'Your response' tab from the top

• I see Warning code displaying between the survey name and the first table

Warning: Division by zero in /vle/www_root/mod/questionnaire/questionnaire.class.php on line 3153 Notice: Undefined offset: 1 in /vle/www_root/mod/questionnaire/questionnaire.class.php on line 3325 Notice: Undefined offset: 2 in /vle/www_root/mod/questionnaire/questionnaire.class.php on line 3325 Notice: Undefined offset: 3 in /vle/www_root/mod/questionnaire/questionnaire.class.php on line 3325 Notice: Undefined offset: 4 in /vle/www_root/mod/questionnaire/questionnaire.class.php on line 3325 Notice: Undefined offset: 5 in /vle/www_root/mod/questionnaire/questionnaire.class.php on line 3325 Notice: Undefined offset: 6 in /vle/www_root/mod/questionnaire/questionnaire.class.php on line 3325 Notice: Undefined offset: 7 in /vle/www_root/mod/questionnaire/questionnaire.class.php on line 3325

This is because it is impossible to compare your result with the results from a group that has no members.

The same thing might happen if the group has members but no responses submitted - but I haven't tested that.

I know some changes to groups have been done for 2.7.x, so I'm not sure if this issue will still be relevant on 2.7. It isn't critical, but nice to fix on the 2.6 branch anyway?