public function scatterplotAction($scope = 'concept', $groupingId = '', $debug = false)
{
$this->view->disable();
// Get our context (this takes care of starting the session, too)
$context = $this->getDI()->getShared('ltiContext');
if (!$context->valid) {
echo '[{"error":"Invalid lti context"}]';
return;
}
// Get the list of questions associated with concepts for the given scope and grouping ID
$questions = [];
switch ($scope) {
case "concept":
// Filter based on concept
$questions = MappingHelper::questionsInConcept($groupingId);
break;
case "unit":
// Filter based on unit
$questions = MappingHelper::questionsInConcepts(MappingHelper::conceptsInUnit($groupingId));
break;
default:
echo '[{"error":"Invalid scope option"}]';
return;
break;
}
if ($debug) {
echo "questions for scope {$scope} and grouping {$groupingId}: \n";
print_r($questions);
}
$classHelper = new ClassHelper();
// Array of questions with more details about each
$questionDetails = array();
// Get some info about each question
foreach ($questions as $question) {
// Check that it's a valid question
if ($question != false) {
// Get number of attempts
$question["attempts"] = MasteryHelper::countAttemptsForQuestion($context->getUserName(), $question["OA Quiz ID"], $question["Question Number"], $debug);
$question["scaledAttemptScore"] = $classHelper->calculateScaledAttemptScoreForQuestion($question["attempts"], $question["OA Quiz ID"], $question["Question Number"], $debug);
// Get amount of associated videos watched
// Note that question ID is being used instead of assessment ID and question number, since we're searching the csv mapping and not dealing with assessment statements here
$question["videoPercentage"] = MasteryHelper::calculateUniqueVideoPercentageForQuestion($context->getUserName(), $questionId);
$questionDetails[] = $question;
}
}
/*
function randomPoint($group, $q) {
// Randomly return outliers
if (rand(0,30) == 5) {
return [$group, $q["quizNumber"], $q["questionNumber"], rand(-10000, 1000), rand(-10000, 1000)];
}
return [$group, $q["quizNumber"], $q["questionNumber"], rand(-100, 100), rand(-100, 100)];
}
$result = [];
// For now, return random points based on number of questions
$numPoints = count($questionDetails);
//foreach ($questionDetails as $q) {
//$result [] =
//}
//
for ($i=0; $i<$numPoints; $i++) {
$result []= randomPoint("student", $questionDetails[$i]);
for ($j=0; $j<10; $j++) {
$result []= randomPoint("class", $questionDetails[$i]);
}
}
$xValues = array_map(function($point) { return $point[3]; }, $result);
$yValues = array_map(function($point) { return $point[4]; }, $result);
// TODO check that xValues and yValues have a length, otherwise statshelper will spit out errors
// Perform some statistics grossness
// Remove any outliers for both axes, based on 1.5*IQR
// Cap and floor x outliers
$xStats = StatsHelper::boxPlotValues($xValues);
$result = array_map(function($point) use ($xStats) {
$x = $point[3];
// Floor upper outliers
if ($x > $xStats['q3'] + (1.5 * $xStats['iqr'])) {
$x = $xStats['q3'] + (.5 * $xStats['iqr']);
}
// Cap lower outliers
if ($x < $xStats['q1'] - (1.5 * $xStats['iqr'])) {
$x = $xStats['q1'] - (.5 * $xStats['iqr']);
}
$point[3] = $x;
return $point;
}, $result);
// Scale all the scores from 0 to 10
// TODO
// Cap and floor y outliers
$yStats = StatsHelper::boxPlotValues($yValues);
$result = array_map(function($point) use ($yStats) {
$y = $point[4];
// Floor upper outliers
if ($y > $yStats['q3'] + (1.5 * $yStats['iqr'])) {
$y = $yStats['q3'] + (.5 * $yStats['iqr']);
}
// Cap lower outliers
if ($y < $yStats['q1'] - (1.5 * $yStats['iqr'])) {
$y = $yStats['q1'] - (.5 * $yStats['iqr']);
}
$point[4] = $y;
return $point;
}, $result);
//print_r($result);
//print_r($yStats);
//die();
*/
// X = video percentage, Y = question attempts
$headerRow = ["group", "quiz_number", "question_number", "x", "y"];
$result = array_map(function ($q) {
return ["student", $q["OA Quiz ID"], $q["Question Number"], $q["videoPercentage"], $q["scaledAttemptScore"]];
}, $questionDetails);
if ($debug) {
echo "question details for scope {$scope} and grouping {$groupingId}: \n";
print_r($questionDetails);
print_r($result);
}
// Output data as csv so that we only have to send header information once for so many points
if (!$debug) {
header("Content-Type: text/csv");
}
$output = fopen("php://output", "w");
fputcsv($output, $headerRow);
foreach ($result as $row) {
fputcsv($output, $row);
// here you can change delimiter/enclosure
}
fclose($output);
}
