public/main/exercise/calculated_answer.class.php
<?php
/* For licensing terms, see /license.txt */
use Webit\Util\EvalMath\EvalMath;
/**
* Class CalculatedAnswer
* This class contains calculated answer form and answer processing functions.
*
* @author Imanol Losada
*/
class CalculatedAnswer extends Question
{
public $typePicture = 'calculated_answer.png';
public $explanationLangVar = 'Calculated question';
/**
* Constructor.
*/
public function __construct()
{
parent::__construct();
$this->type = CALCULATED_ANSWER;
$this->isContent = $this->getIsContent();
}
public function createAnswersForm($form)
{
$defaults = [];
$defaults['answer'] = get_lang('DefaultTextInBlanks');
if (!empty($this->id)) {
$objAnswer = new Answer($this->id);
$preArray = explode('@@', $objAnswer->selectAnswer(1));
$defaults['formula'] = array_pop($preArray);
$defaults['answer'] = array_shift($preArray);
$defaults['answer'] = preg_replace("/\[.*\]/", '', $defaults['answer']);
$defaults['weighting'] = $this->weighting;
}
$lowestValue = '1.00';
$highestValue = '20.00';
// javascript //
echo '<script>
function parseTextNumber(textNumber, floatValue) {
if (textNumber.indexOf(".") > -1) {
textNumber = parseFloat(textNumber);
floatValue.exists = "true";
} else {
textNumber = parseInt(textNumber);
}
return textNumber;
}
function updateRandomValue(element) {
// "floatValue" helps to distinguish between an integer (10) and a float with all 0 decimals (10.00)
var floatValue = { exists: "false" };
var index = (element.name).match(/\[[^\]]*\]/g);
var lowestValue = parseTextNumber(document.getElementById("lowestValue"+index).value, floatValue);
var highestValue = parseTextNumber(document.getElementById("highestValue"+index).value, floatValue);
var result = Math.random() * (highestValue - lowestValue) + lowestValue;
if (floatValue.exists == "true") {
result = parseFloat(result).toFixed(2);
} else {
result = parseInt(result);
}
document.getElementById("randomValue"+index).innerHTML = "'.get_lang('Range value').': " + result;
}
CKEDITOR.on("instanceCreated", function(e) {
if (e.editor.name === "answer") {
e.editor.on("change", updateBlanks);
}
});
var firstTime = true;
function updateBlanks(e) {
if (firstTime) {
field = document.getElementById("answer");
var answer = field.value;
} else {
var answer = e.editor.getData();
}
var blanks = answer.match(/\[[^\]]*\]/g);
var fields = "<div class=\"form-group\"><label class=\"col-sm-2\">'.get_lang('Variable ranges').'</label><div class=\"col-sm-8\"><table>";
if (blanks!=null) {
if (typeof updateBlanks.randomValues === "undefined") {
updateBlanks.randomValues = [];
}
for (i=0 ; i<blanks.length ; i++){
if (document.getElementById("lowestValue["+i+"]") && document.getElementById("highestValue["+i+"]")) {
lowestValue = document.getElementById("lowestValue["+i+"]").value;
highestValue = document.getElementById("highestValue["+i+"]").value;
} else {
lowestValue = '.$lowestValue.'.toFixed(2);
highestValue = '.$highestValue.'.toFixed(2);
for (j=0; j<blanks.length; j++) {
updateBlanks.randomValues[j] = parseFloat(Math.random() * (highestValue - lowestValue) + lowestValue).toFixed(2);
}
}
fields += "<tr><td><label>"+blanks[i]+"</label></td><td><input class=\"span1\" style=\"margin-left: 0em;\" size=\"5\" value=\""+lowestValue+"\" type=\"text\" id=\"lowestValue["+i+"]\" name=\"lowestValue["+i+"]\" onblur=\"updateRandomValue(this)\"/></td><td><input class=\"span1\" style=\"margin-left: 0em; width:80px;\" size=\"5\" value=\""+highestValue+"\" type=\"text\" id=\"highestValue["+i+"]\" name=\"highestValue["+i+"]\" onblur=\"updateRandomValue(this)\"/></td><td><label class=\"span3\" id=\"randomValue["+i+"]\"/>'.get_lang('Range value').': "+updateBlanks.randomValues[i]+"</label></td></tr>";
}
}
document.getElementById("blanks_weighting").innerHTML = fields + "</table></div></div>";
if (firstTime) {
firstTime = false;
}
}
window.onload = updateBlanks;
</script>';
// answer
$form->addElement('label', null, '<br /><br />'.get_lang('Please type your text below').', '.get_lang('and').' '.get_lang('use square brackets [...] to define one or more blanks'));
$form->addHtmlEditor(
'answer',
Display::return_icon('fill_field.png'),
true,
false,
[
'id' => 'answer',
'onkeyup' => 'javascript: updateBlanks(this);',
],
[
'ToolbarSet' => 'TestQuestionDescription',
'Width' => '100%',
'Height' => '350',
]
);
$form->addRule('answer', get_lang('Please type the text'), 'required');
$form->addRule(
'answer',
get_lang('Please define at least one blank with square brackets [...]'),
'regex',
'/\[.*\]/'
);
$form->addElement(
'label',
null,
get_lang('If you want only integer values write both limits without decimals')
);
$form->addHtml('<div id="blanks_weighting"></div>');
$notationListButton = Display::url(
get_lang('Formula notation'),
api_get_path(WEB_CODE_PATH).'exercise/evalmathnotation.php',
[
'class' => 'btn btn--info ajax',
'data-title' => get_lang('Formula notation'),
'_target' => '_blank',
]
);
$form->addElement(
'label',
null,
$notationListButton
);
$form->addText(
'formula',
[get_lang('Formula'), get_lang('Formula sample: sqrt( [x] / [y] ) * ( e ^ ( ln(pi) ) )')],
true,
['id' => 'formula']
);
$form->addRule('formula', get_lang('Please, write the formula'), 'required');
$form->addElement('text', 'weighting', get_lang('Score'), ['id' => 'weighting']);
$form->setDefaults(['weighting' => '10']);
$form->addElement('text', 'answerVariations', get_lang('Question variations'));
$form->addRule(
'answerVariations',
get_lang('GiveQuestion variations'),
'required'
);
$form->setDefaults(['answerVariations' => '1']);
global $text;
// setting the save button here and not in the question class.php
$form->addButtonSave($text, 'submitQuestion');
if (!empty($this->id)) {
$form->setDefaults($defaults);
} else {
if (1 == $this->isContent) {
$form->setDefaults($defaults);
}
}
}
public function processAnswersCreation($form, $exercise)
{
if (!self::isAnswered()) {
$table = Database::get_course_table(TABLE_QUIZ_ANSWER);
Database::delete(
$table,
[
'c_id = ? AND question_id = ?' => [
$this->course['real_id'],
$this->id,
],
]
);
$answer = $form->getSubmitValue('answer');
$formula = $form->getSubmitValue('formula');
$lowestValues = $form->getSubmitValue('lowestValue');
$highestValues = $form->getSubmitValue('highestValue');
$answerVariations = $form->getSubmitValue('answerVariations');
$this->weighting = $form->getSubmitValue('weighting');
// Create as many answers as $answerVariations
for ($j = 0; $j < $answerVariations; $j++) {
$auxAnswer = $answer;
$auxFormula = $formula;
$nb = preg_match_all('/\[[^\]]*\]/', $auxAnswer, $blanks);
if ($nb > 0) {
for ($i = 0; $i < $nb; $i++) {
$blankItem = $blanks[0][$i];
// take random float values when one or both edge values have a decimal point
$randomValue =
false !== strpos($lowestValues[$i], '.') ||
false !== strpos($highestValues[$i], '.') ?
mt_rand($lowestValues[$i] * 100, $highestValues[$i] * 100) / 100 : mt_rand($lowestValues[$i], $highestValues[$i]);
$auxAnswer = str_replace($blankItem, $randomValue, $auxAnswer);
$auxFormula = str_replace($blankItem, $randomValue, $auxFormula);
}
$math = new EvalMath();
$result = $math->evaluate($auxFormula);
$result = number_format($result, 2, '.', '');
// Remove decimal trailing zeros
$result = rtrim($result, '0');
// If it is an integer (ends in .00) remove the decimal point
if ('.' === mb_substr($result, -1)) {
$result = str_replace('.', '', $result);
}
// Attach formula
$auxAnswer .= ' ['.$result.']@@'.$formula;
}
$this->save($exercise);
$objAnswer = new Answer($this->id);
$objAnswer->createAnswer($auxAnswer, 1, '', $this->weighting, '');
$objAnswer->position = [];
$objAnswer->save();
}
}
}
public function return_header(Exercise $exercise, $counter = null, $score = [])
{
$header = parent::return_header($exercise, $counter, $score);
$header .= '<table class="'.$this->questionTableClass.'"><tr>';
$header .= '<th>'.get_lang('Answer').'</th>';
if ($exercise->showExpectedChoice()) {
$header .= '<th>'.get_lang('Your choice').'</th>';
if ($exercise->showExpectedChoiceColumn()) {
$header .= '<th>'.get_lang('Expected choice').'</th>';
}
$header .= '<th class="text-center">'.get_lang('Status').'</th>';
}
$header .= '</tr>';
return $header;
}
/**
* Returns true if the current question has been attempted to be answered.
*
* @return bool
*/
public function isAnswered()
{
$table = Database::get_main_table(TABLE_STATISTIC_TRACK_E_ATTEMPT);
$result = Database::select(
'question_id',
$table,
[
'where' => [
'question_id = ?' => [
$this->id,
],
],
]
);
return empty($result) ? false : true;
}
}