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  • Bug fixes for general core bugs in 4.2.x will end 22 April 2024 (12 months).
  • Bug fixes for security issues in 4.2.x will end 7 October 2024 (18 months).
  • PHP version: minimum PHP 8.0.0 Note: minimum PHP version has increased since Moodle 4.1. PHP 8.1.x is supported too.
<?php
// This file is part of Moodle - http://moodle.org/
//
// 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
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// 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 <http://www.gnu.org/licenses/>.

namespace qbank_statistics;

use core_question\statistics\questions\all_calculated_for_qubaid_condition;
< use quiz;
use quiz_statistics\tests\statistics_helper;
> use mod_quiz\quiz_attempt; use question_engine; > use mod_quiz\quiz_settings;
< use quiz_attempt;
/** * Tests for question statistics. * * @package qbank_statistics * @copyright 2021 Catalyst IT Australia Pty Ltd * @author Nathan Nguyen <nathannguyen@catalyst-au.net> * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later */ class helper_test extends \advanced_testcase { /** * Test quizzes that contain a specified question. * * @covers ::get_all_places_where_questions_were_attempted * @throws \coding_exception * @throws \dml_exception */ public function test_get_all_places_where_questions_were_attempted(): void { $this->resetAfterTest(); $this->setAdminUser(); $rcm = new \ReflectionMethod(helper::class, 'get_all_places_where_questions_were_attempted'); $rcm->setAccessible(true); // Create a course. $course = $this->getDataGenerator()->create_course(); // Create three quizzes. $quizgenerator = $this->getDataGenerator()->get_plugin_generator('mod_quiz'); $quiz1 = $quizgenerator->create_instance([ 'course' => $course->id, 'grade' => 100.0, 'sumgrades' => 2, 'layout' => '1,2,0' ]); $quiz1context = \context_module::instance($quiz1->cmid); $quiz2 = $quizgenerator->create_instance([ 'course' => $course->id, 'grade' => 100.0, 'sumgrades' => 2, 'layout' => '1,2,0' ]); $quiz2context = \context_module::instance($quiz2->cmid); $quiz3 = $quizgenerator->create_instance([ 'course' => $course->id, 'grade' => 100.0, 'sumgrades' => 2, 'layout' => '1,2,0' ]); $quiz3context = \context_module::instance($quiz3->cmid); // Create questions. /** @var \core_question_generator $questiongenerator */ $questiongenerator = $this->getDataGenerator()->get_plugin_generator('core_question'); $cat = $questiongenerator->create_question_category(); $question1 = $questiongenerator->create_question('shortanswer', null, array('category' => $cat->id)); $question2 = $questiongenerator->create_question('numerical', null, array('category' => $cat->id)); // Add question 1 to quiz 1 and make an attempt. quiz_add_quiz_question($question1->id, $quiz1); // Quiz 1 attempt. $this->submit_quiz($quiz1, [1 => ['answer' => 'frog']]); // Add questions 1 and 2 to quiz 2. quiz_add_quiz_question($question1->id, $quiz2); quiz_add_quiz_question($question2->id, $quiz2); $this->submit_quiz($quiz2, [1 => ['answer' => 'frog'], 2 => ['answer' => 10]]); // Checking quizzes that use question 1. $q1places = $rcm->invoke(null, [$question1->id]); $this->assertCount(2, $q1places); $this->assertEquals((object) ['component' => 'mod_quiz', 'contextid' => $quiz1context->id], $q1places[0]); $this->assertEquals((object) ['component' => 'mod_quiz', 'contextid' => $quiz2context->id], $q1places[1]); // Checking quizzes that contain question 2. $q2places = $rcm->invoke(null, [$question2->id]); $this->assertCount(1, $q2places); $this->assertEquals((object) ['component' => 'mod_quiz', 'contextid' => $quiz2context->id], $q2places[0]); // Add a random question to quiz3. quiz_add_random_questions($quiz3, 0, $cat->id, 1, false); $this->submit_quiz($quiz3, [1 => ['answer' => 'willbewrong']]); // Quiz 3 will now be in one of these arrays. $q1places = $rcm->invoke(null, [$question1->id]); $q2places = $rcm->invoke(null, [$question2->id]); if (count($q1places) == 3) { $newplace = end($q1places); } else { $newplace = end($q2places); } $this->assertEquals((object) ['component' => 'mod_quiz', 'contextid' => $quiz3context->id], $newplace); } /** * Create 2 quizzes. * * @return array return 2 quizzes * @throws \coding_exception */ private function prepare_quizzes(): array { // Create a course. $course = $this->getDataGenerator()->create_course(); // Make 2 quizzes. $quizgenerator = $this->getDataGenerator()->get_plugin_generator('mod_quiz'); $layout = '1,2,0,3,4,0'; $quiz1 = $quizgenerator->create_instance([ 'course' => $course->id, 'grade' => 100.0, 'sumgrades' => 2, 'layout' => $layout ]); $quiz2 = $quizgenerator->create_instance([ 'course' => $course->id, 'grade' => 100.0, 'sumgrades' => 2, 'layout' => $layout ]); /** @var \core_question_generator $questiongenerator */ $questiongenerator = $this->getDataGenerator()->get_plugin_generator('core_question'); $cat = $questiongenerator->create_question_category(); $page = 1; $questions = []; foreach (explode(',', $layout) as $slot) { if ($slot == 0) { $page += 1; continue; } $question = $questiongenerator->create_question('shortanswer', null, ['category' => $cat->id]); $questions[$slot] = $question; quiz_add_quiz_question($question->id, $quiz1, $page); quiz_add_quiz_question($question->id, $quiz2, $page); } return [$quiz1, $quiz2, $questions]; } /** * Submit quiz answers * * @param object $quiz * @param array $answers * @throws \moodle_exception */ private function submit_quiz(object $quiz, array $answers): void { // Create user. $user = $this->getDataGenerator()->create_user(); // Create attempt.
< $quizobj = quiz::create($quiz->id, $user->id);
> $quizobj = quiz_settings::create($quiz->id, $user->id);
$quba = question_engine::make_questions_usage_by_activity('mod_quiz', $quizobj->get_context()); $quba->set_preferred_behaviour($quizobj->get_quiz()->preferredbehaviour); $timenow = time(); $attempt = quiz_create_attempt($quizobj, 1, null, $timenow, false, $user->id); quiz_start_new_attempt($quizobj, $quba, $attempt, 1, $timenow); quiz_attempt_save_started($quizobj, $quba, $attempt); // Submit attempt. $attemptobj = quiz_attempt::create($attempt->id); $attemptobj->process_submitted_actions($timenow, false, $answers); $attemptobj->process_finish($timenow, false); } /** * Generate attempt answers. * * @param array $correctanswerflags array of 1 or 0 * 1 : generate correct answer * 0 : generate wrong answer * * @return array */ private function generate_attempt_answers(array $correctanswerflags): array { $attempt = []; for ($i = 1; $i <= 4; $i++) { if (isset($correctanswerflags) && $correctanswerflags[$i - 1] == 1) { // Correct answer. $attempt[$i] = ['answer' => 'frog']; } else { $attempt[$i] = ['answer' => 'false']; } } return $attempt; } /** * * Generate quizzes and submit answers. * * @param array $quiz1attempts quiz 1 attempts * @param array $quiz2attempts quiz 2 attempts * * @return array */ private function prepare_and_submit_quizzes(array $quiz1attempts, array $quiz2attempts): array { list($quiz1, $quiz2, $questions) = $this->prepare_quizzes(); // Submit attempts of quiz1. foreach ($quiz1attempts as $attempt) { $this->submit_quiz($quiz1, $attempt); } // Submit attempts of quiz2. foreach ($quiz2attempts as $attempt) { $this->submit_quiz($quiz2, $attempt); } // Calculate the statistics. $this->expectOutputRegex('~.*Calculations completed.*~'); statistics_helper::run_pending_recalculation_tasks(); return [$quiz1, $quiz2, $questions]; } /** * To use private helper::extract_item_value function. * * @param all_calculated_for_qubaid_condition $statistics the batch of statistics. * @param int $questionid a question id. * @param string $item ane of the field names in all_calculated_for_qubaid_condition, e.g. 'facility'. * @return float|null the required value. */ private function extract_item_value(all_calculated_for_qubaid_condition $statistics, int $questionid, string $item): ?float { $rcm = new \ReflectionMethod(helper::class, 'extract_item_value'); $rcm->setAccessible(true); return $rcm->invoke(null, $statistics, $questionid, $item); } /** * To use private helper::load_statistics_for_place function (with mod_quiz component). * * @param \context $context the context to load the statistics for. * @return all_calculated_for_qubaid_condition|null question statistics. */ private function load_quiz_statistics_for_place(\context $context): ?all_calculated_for_qubaid_condition { $rcm = new \ReflectionMethod(helper::class, 'load_statistics_for_place'); $rcm->setAccessible(true); return $rcm->invoke(null, 'mod_quiz', $context); } /** * Data provider for {@see test_load_question_facility()}. * * @return \Generator */ public function load_question_facility_provider(): \Generator { yield 'Facility case 1' => [ 'Quiz 1 attempts' => [ $this->generate_attempt_answers([1, 0, 0, 0]), ], 'Expected quiz 1 facilities' => ['100.00%', '0.00%', '0.00%', '0.00%'], 'Quiz 2 attempts' => [ $this->generate_attempt_answers([1, 0, 0, 0]), $this->generate_attempt_answers([1, 1, 0, 0]), ], 'Expected quiz 2 facilities' => ['100.00%', '50.00%', '0.00%', '0.00%'], 'Expected average facilities' => ['100.00%', '25.00%', '0.00%', '0.00%'], ]; yield 'Facility case 2' => [ 'Quiz 1 attempts' => [ $this->generate_attempt_answers([1, 0, 0, 0]), $this->generate_attempt_answers([1, 1, 0, 0]), $this->generate_attempt_answers([1, 1, 1, 0]), ], 'Expected quiz 1 facilities' => ['100.00%', '66.67%', '33.33%', '0.00%'], 'Quiz 2 attempts' => [ $this->generate_attempt_answers([1, 0, 0, 0]), $this->generate_attempt_answers([1, 1, 0, 0]), $this->generate_attempt_answers([1, 1, 1, 0]), $this->generate_attempt_answers([1, 1, 1, 1]), ], 'Expected quiz 2 facilities' => ['100.00%', '75.00%', '50.00%', '25.00%'], 'Expected average facilities' => ['100.00%', '70.83%', '41.67%', '12.50%'], ]; } /** * Test question facility * * @dataProvider load_question_facility_provider * * @param array $quiz1attempts quiz 1 attempts * @param array $expectedquiz1facilities expected quiz 1 facilities * @param array $quiz2attempts quiz 2 attempts * @param array $expectedquiz2facilities expected quiz 2 facilities * @param array $expectedaveragefacilities expected average facilities */ public function test_load_question_facility( array $quiz1attempts, array $expectedquiz1facilities, array $quiz2attempts, array $expectedquiz2facilities, array $expectedaveragefacilities) : void { $this->resetAfterTest(); list($quiz1, $quiz2, $questions) = $this->prepare_and_submit_quizzes($quiz1attempts, $quiz2attempts); // Quiz 1 facilities. $stats = $this->load_quiz_statistics_for_place(\context_module::instance($quiz1->cmid)); $quiz1facility1 = $this->extract_item_value($stats, $questions[1]->id, 'facility'); $quiz1facility2 = $this->extract_item_value($stats, $questions[2]->id, 'facility'); $quiz1facility3 = $this->extract_item_value($stats, $questions[3]->id, 'facility'); $quiz1facility4 = $this->extract_item_value($stats, $questions[4]->id, 'facility'); $this->assertEquals($expectedquiz1facilities[0], helper::format_percentage($quiz1facility1)); $this->assertEquals($expectedquiz1facilities[1], helper::format_percentage($quiz1facility2)); $this->assertEquals($expectedquiz1facilities[2], helper::format_percentage($quiz1facility3)); $this->assertEquals($expectedquiz1facilities[3], helper::format_percentage($quiz1facility4)); // Quiz 2 facilities. $stats = $this->load_quiz_statistics_for_place(\context_module::instance($quiz2->cmid)); $quiz2facility1 = $this->extract_item_value($stats, $questions[1]->id, 'facility'); $quiz2facility2 = $this->extract_item_value($stats, $questions[2]->id, 'facility'); $quiz2facility3 = $this->extract_item_value($stats, $questions[3]->id, 'facility'); $quiz2facility4 = $this->extract_item_value($stats, $questions[4]->id, 'facility'); $this->assertEquals($expectedquiz2facilities[0], helper::format_percentage($quiz2facility1)); $this->assertEquals($expectedquiz2facilities[1], helper::format_percentage($quiz2facility2)); $this->assertEquals($expectedquiz2facilities[2], helper::format_percentage($quiz2facility3)); $this->assertEquals($expectedquiz2facilities[3], helper::format_percentage($quiz2facility4)); // Average question facilities. $averagefacility1 = helper::calculate_average_question_facility($questions[1]->id); $averagefacility2 = helper::calculate_average_question_facility($questions[2]->id); $averagefacility3 = helper::calculate_average_question_facility($questions[3]->id); $averagefacility4 = helper::calculate_average_question_facility($questions[4]->id); $this->assertEquals($expectedaveragefacilities[0], helper::format_percentage($averagefacility1)); $this->assertEquals($expectedaveragefacilities[1], helper::format_percentage($averagefacility2)); $this->assertEquals($expectedaveragefacilities[2], helper::format_percentage($averagefacility3)); $this->assertEquals($expectedaveragefacilities[3], helper::format_percentage($averagefacility4)); } /** * Data provider for {@see test_load_question_discriminative_efficiency()}. * @return \Generator */ public function load_question_discriminative_efficiency_provider(): \Generator { yield 'Discriminative efficiency' => [ 'Quiz 1 attempts' => [ $this->generate_attempt_answers([1, 0, 0, 0]), $this->generate_attempt_answers([1, 1, 0, 0]), $this->generate_attempt_answers([1, 0, 1, 0]), $this->generate_attempt_answers([1, 1, 1, 1]), ], 'Expected quiz 1 discriminative efficiency' => ['N/A', '33.33%', '33.33%', '100.00%'], 'Quiz 2 attempts' => [ $this->generate_attempt_answers([1, 1, 1, 1]), $this->generate_attempt_answers([0, 0, 0, 0]), $this->generate_attempt_answers([1, 0, 0, 1]), $this->generate_attempt_answers([0, 1, 1, 0]), ], 'Expected quiz 2 discriminative efficiency' => ['50.00%', '50.00%', '50.00%', '50.00%'], 'Expected average discriminative efficiency' => ['50.00%', '41.67%', '41.67%', '75.00%'], ]; } /** * Test discriminative efficiency * * @dataProvider load_question_discriminative_efficiency_provider * * @param array $quiz1attempts quiz 1 attempts * @param array $expectedquiz1discriminativeefficiency expected quiz 1 discriminative efficiency * @param array $quiz2attempts quiz 2 attempts * @param array $expectedquiz2discriminativeefficiency expected quiz 2 discriminative efficiency * @param array $expectedaveragediscriminativeefficiency expected average discriminative efficiency */ public function test_load_question_discriminative_efficiency( array $quiz1attempts, array $expectedquiz1discriminativeefficiency, array $quiz2attempts, array $expectedquiz2discriminativeefficiency, array $expectedaveragediscriminativeefficiency ): void { $this->resetAfterTest(); list($quiz1, $quiz2, $questions) = $this->prepare_and_submit_quizzes($quiz1attempts, $quiz2attempts); // Quiz 1 discriminative efficiency. $stats = $this->load_quiz_statistics_for_place(\context_module::instance($quiz1->cmid)); $discriminativeefficiency1 = $this->extract_item_value($stats, $questions[1]->id, 'discriminativeefficiency'); $discriminativeefficiency2 = $this->extract_item_value($stats, $questions[2]->id, 'discriminativeefficiency'); $discriminativeefficiency3 = $this->extract_item_value($stats, $questions[3]->id, 'discriminativeefficiency'); $discriminativeefficiency4 = $this->extract_item_value($stats, $questions[4]->id, 'discriminativeefficiency'); $this->assertEquals($expectedquiz1discriminativeefficiency[0], helper::format_percentage($discriminativeefficiency1, false), "Failure in quiz 1 - question 1 discriminative efficiency"); $this->assertEquals($expectedquiz1discriminativeefficiency[1], helper::format_percentage($discriminativeefficiency2, false), "Failure in quiz 1 - question 2 discriminative efficiency"); $this->assertEquals($expectedquiz1discriminativeefficiency[2], helper::format_percentage($discriminativeefficiency3, false), "Failure in quiz 1 - question 3 discriminative efficiency"); $this->assertEquals($expectedquiz1discriminativeefficiency[3], helper::format_percentage($discriminativeefficiency4, false), "Failure in quiz 1 - question 4 discriminative efficiency"); // Quiz 2 discriminative efficiency. $stats = $this->load_quiz_statistics_for_place(\context_module::instance($quiz2->cmid)); $discriminativeefficiency1 = $this->extract_item_value($stats, $questions[1]->id, 'discriminativeefficiency'); $discriminativeefficiency2 = $this->extract_item_value($stats, $questions[2]->id, 'discriminativeefficiency'); $discriminativeefficiency3 = $this->extract_item_value($stats, $questions[3]->id, 'discriminativeefficiency'); $discriminativeefficiency4 = $this->extract_item_value($stats, $questions[4]->id, 'discriminativeefficiency'); $this->assertEquals($expectedquiz2discriminativeefficiency[0], helper::format_percentage($discriminativeefficiency1, false), "Failure in quiz 2 - question 1 discriminative efficiency"); $this->assertEquals($expectedquiz2discriminativeefficiency[1], helper::format_percentage($discriminativeefficiency2, false), "Failure in quiz 2 - question 2 discriminative efficiency"); $this->assertEquals($expectedquiz2discriminativeefficiency[2], helper::format_percentage($discriminativeefficiency3, false), "Failure in quiz 2 - question 3 discriminative efficiency"); $this->assertEquals($expectedquiz2discriminativeefficiency[3], helper::format_percentage($discriminativeefficiency4, false), "Failure in quiz 2 - question 4 discriminative efficiency"); // Average question discriminative efficiency. $avgdiscriminativeefficiency1 = helper::calculate_average_question_discriminative_efficiency($questions[1]->id); $avgdiscriminativeefficiency2 = helper::calculate_average_question_discriminative_efficiency($questions[2]->id); $avgdiscriminativeefficiency3 = helper::calculate_average_question_discriminative_efficiency($questions[3]->id); $avgdiscriminativeefficiency4 = helper::calculate_average_question_discriminative_efficiency($questions[4]->id); $this->assertEquals($expectedaveragediscriminativeefficiency[0], helper::format_percentage($avgdiscriminativeefficiency1, false), "Failure in question 1 average discriminative efficiency"); $this->assertEquals($expectedaveragediscriminativeefficiency[1], helper::format_percentage($avgdiscriminativeefficiency2, false), "Failure in question 2 average discriminative efficiency"); $this->assertEquals($expectedaveragediscriminativeefficiency[2], helper::format_percentage($avgdiscriminativeefficiency3, false), "Failure in question 3 average discriminative efficiency"); $this->assertEquals($expectedaveragediscriminativeefficiency[3], helper::format_percentage($avgdiscriminativeefficiency4, false), "Failure in question 4 average discriminative efficiency"); } /** * Data provider for {@see test_load_question_discrimination_index()}. * @return \Generator */ public function load_question_discrimination_index_provider(): \Generator { yield 'Discrimination Index' => [ 'Quiz 1 attempts' => [ $this->generate_attempt_answers([1, 0, 0, 0]), $this->generate_attempt_answers([1, 1, 0, 0]), $this->generate_attempt_answers([1, 0, 1, 0]), $this->generate_attempt_answers([1, 1, 1, 1]), ], 'Expected quiz 1 Discrimination Index' => ['N/A', '30.15%', '30.15%', '81.65%'], 'Quiz 2 attempts' => [ $this->generate_attempt_answers([1, 1, 1, 1]), $this->generate_attempt_answers([0, 0, 0, 0]), $this->generate_attempt_answers([1, 0, 0, 1]), $this->generate_attempt_answers([0, 1, 1, 0]), ], 'Expected quiz 2 discrimination Index' => ['44.72%', '44.72%', '44.72%', '44.72%'], 'Expected average discrimination Index' => ['44.72%', '37.44%', '37.44%', '63.19%'], ]; } /** * Test discrimination index * * @dataProvider load_question_discrimination_index_provider * * @param array $quiz1attempts quiz 1 attempts * @param array $expectedquiz1discriminationindex expected quiz 1 discrimination index * @param array $quiz2attempts quiz 2 attempts * @param array $expectedquiz2discriminationindex expected quiz 2 discrimination index * @param array $expectedaveragediscriminationindex expected average discrimination index */ public function test_load_question_discrimination_index( array $quiz1attempts, array $expectedquiz1discriminationindex, array $quiz2attempts, array $expectedquiz2discriminationindex, array $expectedaveragediscriminationindex ): void { $this->resetAfterTest(); list($quiz1, $quiz2, $questions) = $this->prepare_and_submit_quizzes($quiz1attempts, $quiz2attempts); // Quiz 1 discrimination index. $stats = $this->load_quiz_statistics_for_place(\context_module::instance($quiz1->cmid)); $discriminationindex1 = $this->extract_item_value($stats, $questions[1]->id, 'discriminationindex'); $discriminationindex2 = $this->extract_item_value($stats, $questions[2]->id, 'discriminationindex'); $discriminationindex3 = $this->extract_item_value($stats, $questions[3]->id, 'discriminationindex'); $discriminationindex4 = $this->extract_item_value($stats, $questions[4]->id, 'discriminationindex'); $this->assertEquals($expectedquiz1discriminationindex[0], helper::format_percentage($discriminationindex1, false), "Failure in quiz 1 - question 1 discrimination index"); $this->assertEquals($expectedquiz1discriminationindex[1], helper::format_percentage($discriminationindex2, false), "Failure in quiz 1 - question 2 discrimination index"); $this->assertEquals($expectedquiz1discriminationindex[2], helper::format_percentage($discriminationindex3, false), "Failure in quiz 1 - question 3 discrimination index"); $this->assertEquals($expectedquiz1discriminationindex[3], helper::format_percentage($discriminationindex4, false), "Failure in quiz 1 - question 4 discrimination index"); // Quiz 2 discrimination index. $stats = $this->load_quiz_statistics_for_place(\context_module::instance($quiz2->cmid)); $discriminationindex1 = $this->extract_item_value($stats, $questions[1]->id, 'discriminationindex'); $discriminationindex2 = $this->extract_item_value($stats, $questions[2]->id, 'discriminationindex'); $discriminationindex3 = $this->extract_item_value($stats, $questions[3]->id, 'discriminationindex'); $discriminationindex4 = $this->extract_item_value($stats, $questions[4]->id, 'discriminationindex'); $this->assertEquals($expectedquiz2discriminationindex[0], helper::format_percentage($discriminationindex1, false), "Failure in quiz 2 - question 1 discrimination index"); $this->assertEquals($expectedquiz2discriminationindex[1], helper::format_percentage($discriminationindex2, false), "Failure in quiz 2 - question 2 discrimination index"); $this->assertEquals($expectedquiz2discriminationindex[2], helper::format_percentage($discriminationindex3, false), "Failure in quiz 2 - question 3 discrimination index"); $this->assertEquals($expectedquiz2discriminationindex[3], helper::format_percentage($discriminationindex4, false), "Failure in quiz 2 - question 4 discrimination index"); // Average question discrimination index. $avgdiscriminationindex1 = helper::calculate_average_question_discrimination_index($questions[1]->id); $avgdiscriminationindex2 = helper::calculate_average_question_discrimination_index($questions[2]->id); $avgdiscriminationindex3 = helper::calculate_average_question_discrimination_index($questions[3]->id); $avgdiscriminationindex4 = helper::calculate_average_question_discrimination_index($questions[4]->id); $this->assertEquals($expectedaveragediscriminationindex[0], helper::format_percentage($avgdiscriminationindex1, false), "Failure in question 1 average discrimination index"); $this->assertEquals($expectedaveragediscriminationindex[1], helper::format_percentage($avgdiscriminationindex2, false), "Failure in question 2 average discrimination index"); $this->assertEquals($expectedaveragediscriminationindex[2], helper::format_percentage($avgdiscriminationindex3, false), "Failure in question 3 average discrimination index"); $this->assertEquals($expectedaveragediscriminationindex[3], helper::format_percentage($avgdiscriminationindex4, false), "Failure in question 4 average discrimination index"); } }