See Release Notes
Long Term Support Release
<?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/>. /**< * Upgrade library code for the calculated multiple-choice question type. < * < * @package qtype < * @subpackage calculatedmulti < * @copyright 2011 The Open University < * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later < */ < < < defined('MOODLE_INTERNAL') || die(); < < < /*** Class for converting attempt data for calculated multiple-choice questions * when upgrading attempts to the new question engine. * * This class is used by the code in question/engine/upgrade/upgradelib.php. *> * @package qtype_calculatedmulti* @copyright 2011 The Open University * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later */ class qtype_calculatedmulti_qe2_attempt_updater extends question_qtype_attempt_updater { protected $selecteditem = null; /** @var array variable name => value */< protected $values;> protected $values = [];/** @var array variable names wrapped in {...}. Used by {@link substitute_values()}. */< protected $search;> protected $search = [];/** * @var array variable values, with negative numbers wrapped in (...). * Used by {@link substitute_values()}. */< protected $safevalue;> protected $safevalue = [];/** * @var array variable values, with negative numbers wrapped in (...). * Used by {@link substitute_values()}. */< protected $prettyvalue;> protected $prettyvalue = [];protected $order; public function question_summary() { return ''; // Done later, after we know which dataset is used. } public function right_answer() { if ($this->question->options->single) { foreach ($this->question->options->answers as $ans) { if ($ans->fraction > 0.999) { return $this->to_text($this->replace_expressions_in_text($ans->answer)); } }<} else {< $rightbits = array();> $rightbits = [];foreach ($this->question->options->answers as $ans) { if ($ans->fraction >= 0.000001) { $rightbits[] = $this->to_text($this->replace_expressions_in_text($ans->answer)); } } return implode('; ', $rightbits); } } protected function explode_answer($state) { if (strpos($state->answer, '-') < 7) { // Broken state, skip it. throw new coding_exception("Brokes state {$state->id} for calcluatedmulti question {$state->question}. (It did not specify a dataset."); }< list($datasetbit, $answer) = explode('-', $state->answer, 2);> [$datasetbit, $answer] = explode('-', $state->answer, 2);$selecteditem = substr($datasetbit, 7); if (is_null($this->selecteditem)) { $this->load_dataset($selecteditem); } else if ($this->selecteditem != $selecteditem) { $this->logger->log_assumption("Different states for calcluatedmulti question {$state->question} used different dataset items. Ignoring the change in state {$state->id} and coninuting to use item {$this->selecteditem}."); } if (strpos($answer, ':') !== false) {< list($order, $responses) = explode(':', $answer);> [$order, $responses] = explode(':', $answer);return $responses; } else { // Sometimes, a bug means that a state is missing the <order>: bit, // We need to deal with that. $this->logger->log_assumption("Dealing with missing order information in attempt at multiple choice question {$this->question->id}"); return $answer; } } public function response_summary($state) { $responses = $this->explode_answer($state); if ($this->question->options->single) { if (is_numeric($responses)) { if (array_key_exists($responses, $this->question->options->answers)) { return $this->to_text($this->replace_expressions_in_text(< $this->question->options->answers[$responses]->answer));> $this->question->options->answers[$responses]->answer > ));} else { $this->logger->log_assumption("Dealing with a place where the student selected a choice that was later deleted for multiple choice question {$this->question->id}"); return '[CHOICE THAT WAS LATER DELETED]'; } } else { return null; }<} else { if (!empty($responses)) { $responses = explode(',', $responses);< $bits = array();> $bits = [];foreach ($responses as $response) { if (array_key_exists($response, $this->question->options->answers)) { $bits[] = $this->to_text($this->replace_expressions_in_text(< $this->question->options->answers[$response]->answer));> $this->question->options->answers[$response]->answer > ));} else { $this->logger->log_assumption("Dealing with a place where the student selected a choice that was later deleted for multiple choice question {$this->question->id}"); $bits[] = '[CHOICE THAT WAS LATER DELETED]'; } } return implode('; ', $bits); } else { return null; } } } public function was_answered($state) { $responses = $this->explode_answer($state); if ($this->question->options->single) { return is_numeric($responses); } else { return !empty($responses); } } public function set_first_step_data_elements($state, &$data) { $this->explode_answer($state); $this->updater->qa->questionsummary = $this->to_text(< $this->replace_expressions_in_text($this->question->questiontext));> $this->replace_expressions_in_text($this->question->questiontext) > );$this->updater->qa->rightanswer = $this->right_answer($this->question); foreach ($this->values as $name => $value) { $data['_var_' . $name] = $value; }< list($datasetbit, $answer) = explode('-', $state->answer, 2); < list($order, $responses) = explode(':', $answer);> [$datasetbit, $answer] = explode('-', $state->answer, 2); > [$order, $responses] = explode(':', $answer);$data['_order'] = $order; $this->order = explode(',', $order); } public function supply_missing_first_step_data(&$data) { $data['_order'] = implode(',', array_keys($this->question->options->answers)); } public function set_data_elements_for_step($state, &$data) { $responses = $this->explode_answer($state); if ($this->question->options->single) { if (is_numeric($responses)) { $flippedorder = array_combine(array_values($this->order), array_keys($this->order)); if (array_key_exists($responses, $flippedorder)) { $data['answer'] = $flippedorder[$responses]; } else { $data['answer'] = '-1'; } }<} else { $responses = explode(',', $responses); foreach ($this->order as $key => $ansid) { if (in_array($ansid, $responses)) { $data['choice' . $key] = 1; } else { $data['choice' . $key] = 0; } } } } public function load_dataset($selecteditem) { $this->selecteditem = $selecteditem; $this->updater->qa->variant = $selecteditem; $this->values = $this->qeupdater->load_dataset(< $this->question->id, $selecteditem);> $this->question->id, > $selecteditem > );// Prepare an array for {@link substitute_values()}.< $this->search = array(); < $this->safevalue = array(); < $this->prettyvalue = array();> $this->search = []; > $this->safevalue = []; > $this->prettyvalue = [];foreach ($this->values as $name => $value) { if (!is_numeric($value)) { $a = new stdClass(); $a->name = '{' . $name . '}'; $a->value = $value; throw new moodle_exception('notvalidnumber', 'qtype_calculated', '', $a); } $this->search[] = '{' . $name . '}'; $this->safevalue[] = '(' . $value . ')'; $this->prettyvalue[] = $this->format_float($value); } } /** * This function should be identical to * {@link qtype_calculated_variable_substituter::format_float()}. Except that * we do not try to do locale-aware replacement of the decimal point. * * Having to copy it here is a pain, but it is the standard rule about not * using library code (which may change in future) in upgrade code, which * exists at a point in time. * * Display a float properly formatted with a certain number of decimal places. * @param number $x the number to format * @param int $length restrict to this many decimal places or significant * figures. If null, the number is not rounded. * @param int format 1 => decimalformat, 2 => significantfigures. * @return string formtted number. */ public function format_float($x, $length = null, $format = null) { if (!is_null($length) && !is_null($format)) { if ($format == 1) { // Decimal places. $x = sprintf('%.' . $length . 'F', $x); } else if ($format == 2) { // Significant figures. $x = sprintf('%.' . $length . 'g', $x); } } return $x; } /** * Evaluate an expression using the variable values. * @param string $expression the expression. A PHP expression with placeholders * like {a} for where the variables need to go. * @return float the computed result. */ public function calculate($expression) { return $this->calculate_raw($this->substitute_values_for_eval($expression)); } /** * Evaluate an expression after the variable values have been substituted. * @param string $expression the expression. A PHP expression with placeholders * like {a} for where the variables need to go. * @return float the computed result. */ protected function calculate_raw($expression) { try { // In older PHP versions this this is a way to validate code passed to eval. // The trick came from http://php.net/manual/en/function.eval.php. if (@eval('return true; $result = ' . $expression . ';')) { return eval('return ' . $expression . ';'); } } catch (Throwable $e) { // PHP7 and later now throws ParseException and friends from eval(), // which is much better. } // In either case of an invalid $expression, we end here. return '[Invalid expression ' . $expression . ']'; } /** * Substitute variable placehodlers like {a} with their value wrapped in (). * @param string $expression the expression. A PHP expression with placeholders * like {a} for where the variables need to go. * @return string the expression with each placeholder replaced by the * corresponding value. */ protected function substitute_values_for_eval($expression) {< return str_replace($this->search, $this->safevalue, $expression);> return str_replace($this->search, $this->safevalue, $expression ?? '');} /** * Substitute variable placehodlers like {a} with their value without wrapping * the value in anything. * @param string $text some content with placeholders * like {a} for where the variables need to go. * @return string the expression with each placeholder replaced by the * corresponding value. */ protected function substitute_values_pretty($text) {< return str_replace($this->search, $this->prettyvalue, $text);> return str_replace($this->search, $this->prettyvalue, $text ?? '');} /** * Replace any embedded variables (like {a}) or formulae (like {={a} + {b}}) * in some text with the corresponding values. * @param string $text the text to process. * @return string the text with values substituted. */ public function replace_expressions_in_text($text, $length = null, $format = null) {> if ($text === null || $text === '') { $vs = $this; // Can't see to use $this in a PHP closure. > return $text; $text = preg_replace_callback(qtype_calculated::FORMULAS_IN_TEXT_REGEX, > } function ($matches) use ($vs, $format, $length) { >< $text = preg_replace_callback(qtype_calculated::FORMULAS_IN_TEXT_REGEX,> $text = preg_replace_callback( > qtype_calculated::FORMULAS_IN_TEXT_REGEX,< }, $text);> }, > $text > );return $this->substitute_values_pretty($text); } }