/**
* getAverageRating
*/
public function getAverageRating($survey_id, $relation_subject = false)
{
if (!is_numeric($survey_id)) {
return false;
}
require_once 'models/education/education_survey_entry.php';
$SurveyEntry = new education_survey_entry();
$average_rating = $SurveyEntry->getWeightedMean($survey_id, $relation_subject);
if (is_numeric($average_rating)) {
return $average_rating;
} else {
return 'n/a';
}
}
/**
* calculateSurveyAverageRating
*/
public function calculateSurveyAverageRating($survey_detail, $relation_subject = fals)
{
if (!is_array($survey_detail)) {
return false;
}
if (!is_array($survey_detail['question_list'])) {
return false;
}
$survey_total_x = 0;
$survey_total_sum = 0;
foreach ($survey_detail['question_list'] as $k => $item) {
$question_total_x = 0;
$question_total_sum = 0;
if (($item['type'] == 'radio' || $item['type'] == 'select') && is_array($item['answer_list'])) {
foreach ($item['answer_list'] as $answer_k => $answer_item) {
$question_total_x = $question_total_x + $answer_item['usage_count'] * $answer_item['points'];
$question_total_sum = $question_total_sum + $answer_item['usage_count'];
}
if ($question_total_sum > 0) {
$survey_detail['question_list'][$k]['average_rating'] = $question_total_x / $question_total_sum;
} else {
$survey_detail['question_list'][$k]['average_rating'] = 'n/a';
}
} else {
$survey_detail['question_list'][$k]['average_rating'] = 'n/a';
}
$survey_total_x = $survey_total_x + $question_total_x;
$survey_total_sum = $survey_total_sum + $question_total_sum;
}
if ($survey_total_sum > 0) {
$survey_detail['average_rating'] = $survey_total_x / $survey_total_sum;
} else {
$survey_detail['average_rating'] = 'n/a';
}
/**
* weighted mean rating
* calculating manually at this place, but we could use education_survey_entry->getWeightedMean()
*/
/* Option 1: manual
$weighted_mean_top = 0;
$weighted_mean_bottom = 0;
foreach ($survey_detail['question_list'] as $k=>$item) {
if (is_numeric($item['average_rating'])) {
$weighted_mean_top = $weighted_mean_top + $item['weight'] * $item['average_rating'];
$weighted_mean_bottom = $weighted_mean_bottom + $item['weight'];
}
}
if ($weighted_mean_bottom > 0) {
$survey_detail['weighted_mean'] = $weighted_mean_top / $weighted_mean_bottom;
} else {
$survey_detail['weighted_mean'] = 'n/a';
}*/
// Option 2: weighted mean calculated from education_survey_entry->getWeightedMean()
require_once 'models/education/education_survey_entry.php';
$SurveyEntry = new education_survey_entry();
$weighted_mean = $SurveyEntry->getWeightedMean($survey_detail['id'], $relation_subject);
if (is_numeric($weighted_mean)) {
$survey_detail['weighted_mean'] = $weighted_mean;
} else {
$survey_detail['weighted_mean'] = 'n/a';
}
return $survey_detail;
}
