Skip to content


Subversion checkout URL

You can clone with
Download ZIP
Fetching contributors…

Cannot retrieve contributors at this time

95 lines (84 sloc) 3.92 kB
// This file is part of Moodle -
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Moodle. If not, see <>.
* Question behaviour that is like the interactive behaviour, but where the
* student is credited for parts of the question they got right on earlier tries.
* @package qbehaviour
* @subpackage interactivecountback
* @copyright 2009 The Open University
* @license GNU GPL v3 or later
defined('MOODLE_INTERNAL') || die();
require_once(dirname(__FILE__) . '/../interactive/behaviour.php');
* Question behaviour for interactive mode with count-back scoring.
* As an example, suppose we have a matching question with 4 parts, and 3 tries
* (penalty 1/3), and the question is worth 12 marks (so, 3 marks for each part).
* Suppose also that:
* - on the first try, the student gets the first two parts right, and the
* other two wrong.
* - on the second try, they are sure they got the first part right, so keep
* their answer the same, but they change their answer to the second part.
* They also get the answer to the thrid part right on this try, but still
* get the 4th part wrong.
* - On the final try, they get the first 3 parts right, but the 4th part still
* wrong.
* We want to grade them as follows.
* - For the first part, they were right first time, and did not change their
* answer, so we credit that part as right first time: 3/3
* - For the second part, although they were right first time, they then changed
* their mind, an only finally got it right on the third try, so 1/3.
* - For the third part, they got it right on the second try, and then did not
* change their answer, so 2/3.
* - For the last part, they were wrong at the last try, so 0/3.
* So, total mark is 6/12. (Really, a fraction of 0.5.)
* Of course, the details of the grading are acutally up to the particular
* question type. The point is that the final grade can take into account all
* of the tries the student made.
* @copyright 2009 The Open University
* @license GNU GPL v3 or later
class qbehaviour_interactivecountback extends qbehaviour_interactive {
const IS_ARCHETYPAL = false;
public function is_compatible_question(question_definition $question) {
return $question instanceof question_automatically_gradable_with_countback;
protected function adjust_fraction($fraction, question_attempt_pending_step $pendingstep) {
$totaltries = $this->qa->get_step(0)->get_behaviour_var('_triesleft');
$responses = array();
$lastsave = array();
foreach ($this->qa->get_step_iterator() as $step) {
if ($step->has_behaviour_var('submit') &&
$step->get_state() != question_state::$invalid) {
$responses[] = $step->get_qt_data();
$lastsave = array();
} else {
$lastsave = $step->get_qt_data();
$lastresponse = $pendingstep->get_qt_data();
if (!empty($lastresponse)) {
$responses[] = $lastresponse;
} else if (!empty($lastsave)) {
$responses[] = $lastsave;
return $this->question->compute_final_grade($responses, $totaltries);
Jump to Line
Something went wrong with that request. Please try again.