/**
* Output a graph as SVG.
* @param stack_abstract_graph $g the graph to display.
* @param string $id an id to add to the SVG node in the HTML.
*/
public static function render(stack_abstract_graph $g, $id)
{
$renderer = new self($g);
list($minx, $maxx) = $g->x_range();
$width = ceil((2 + $maxx - $minx) * self::SCALE / 2);
$height = ceil((0.3 + $g->max_depth()) * self::SCALE);
$output = '';
$output .= html_writer::start_tag('svg', array('id' => $id, 'class' => 'stack_abstract_graph', 'width' => $width . 'px', 'height' => $height . 'px', 'version' => '1.1', 'xmlns' => 'http://www.w3.org/2000/svg'));
$output .= $renderer->to_svg();
$output .= html_writer::end_tag('svg');
return $output;
}
/**
* Get a stack_abstract_graph represemtatopm of a PRT.
* @return stack_abstract_graph.
*/
protected function get_prt_graph($prt)
{
$graph = new stack_abstract_graph();
foreach ($prt->get_nodes_summary() as $nodekey => $summary) {
if ($summary->truenextnode == -1) {
$left = null;
} else {
$left = $summary->truenextnode + 1;
}
if ($summary->falsenextnode == -1) {
$right = null;
} else {
$right = $summary->falsenextnode + 1;
}
$graph->add_node($nodekey + 1, $left, $right, $summary->truescoremode . round($summary->truescore, 2), $summary->falsescoremode . round($summary->falsescore, 2));
}
$graph->layout();
return $graph;
}
/**
* Get a list of the PRT notes that should be present for a given PRT.
* @param string $prtname the name of a PRT.
* @return array list of nodes that should be present in the form definitino for this PRT.
*/
protected function get_prt_graph($prtname)
{
if (array_key_exists($prtname, $this->prtgraph)) {
return $this->prtgraph[$prtname];
}
// If the form has been submitted and is being redisplayed, and this is
// an existing PRT, base things on the submitted data.
$submitted = optional_param_array($prtname . 'truenextnode', null, PARAM_RAW);
if ($submitted) {
$truescoremode = optional_param_array($prtname . 'truescoremode', null, PARAM_RAW);
$truescore = optional_param_array($prtname . 'truescore', null, PARAM_RAW);
$falsenextnode = optional_param_array($prtname . 'falsenextnode', null, PARAM_RAW);
$falsescoremode = optional_param_array($prtname . 'falsescoremode', null, PARAM_RAW);
$falsescore = optional_param_array($prtname . 'falsescore', null, PARAM_RAW);
$graph = new stack_abstract_graph();
$deletednode = null;
$lastkey = -1;
foreach ($submitted as $key => $truenextnode) {
if (optional_param($prtname . 'nodedelete' . $key, false, PARAM_BOOL)) {
// Slightly odd to register the button here, especially since
// now this node has been deleted, this button will not exist,
// but anyway this works, and in necessary to stop the form
// from being submitted.
$this->_form->registerNoSubmitButton($prtname . 'nodedelete' . $key);
// For deleted nodes, we add them to the tree anyway, and
// then remove them again below. We have to do it that way
// because we also need to delete links that point to the
// deleted node.
$deletednode = $key;
}
if ($truenextnode == -1 || !array_key_exists($truenextnode, $submitted)) {
$left = null;
} else {
$left = $truenextnode + 1;
}
if ($falsenextnode[$key] == -1 || !array_key_exists($falsenextnode[$key], $submitted)) {
$right = null;
} else {
$right = $falsenextnode[$key] + 1;
}
$graph->add_node($key + 1, $left, $right, $truescoremode[$key] . round($truescore[$key], 2), $falsescoremode[$key] . round($falsescore[$key], 2), '#fgroup_id_' . $prtname . 'node_' . $key);
$lastkey = max($lastkey, $key);
}
if (optional_param($prtname . 'nodeadd', false, PARAM_BOOL)) {
$graph->add_node($lastkey + 2, null, null, '+0', '-0', '#fgroup_id_' . $prtname . 'node_' . $lastkey + 1);
}
if (!is_null($deletednode)) {
$graph->remove_node($deletednode + 1);
}
$graph->layout();
$this->prtgraph[$prtname] = $graph;
return $graph;
}
// Otherwise, if an existing question is being edited, and this is an
// existing PRT, base things on the existing question definition.
if (!empty($this->question->prts[$prtname]->nodes)) {
$graph = new stack_abstract_graph();
foreach ($this->question->prts[$prtname]->nodes as $node) {
if ($node->truenextnode == -1) {
$left = null;
} else {
$left = $node->truenextnode + 1;
}
if ($node->falsenextnode == -1) {
$right = null;
} else {
$right = $node->falsenextnode + 1;
}
$graph->add_node($node->nodename + 1, $left, $right, $node->truescoremode . round($node->truescore, 2), $node->falsescoremode . round($node->falsescore, 2), '#fgroup_id_' . $prtname . 'node_' . $node->nodename);
}
$graph->layout();
$this->prtgraph[$prtname] = $graph;
return $graph;
}
// Otherwise, it is a new PRT. Just one node.
$graph = new stack_abstract_graph();
$graph->add_node('1', null, null, '=1', '=0', '#fgroup_id_' . $prtname . 'node_0');
$graph->layout();
$this->prtgraph[$prtname] = $graph;
return $graph;
}
/**
* This graph has a link to a non-existent node. We verify that throws an exception.
*/
public function test_get_suggested_node_names()
{
$graph = new stack_abstract_graph();
$graph->add_node(1, 2, 3);
$graph->add_node(2, 7, null);
$graph->add_node(3, 2, 4);
$graph->add_node(4, 5, 6);
$graph->add_node(5, null, 9);
$graph->add_node(6, null, null);
$graph->add_node(7, null, null);
$graph->add_node(9, null, null);
$graph->layout();
$newnames = $graph->get_suggested_node_names();
$this->assertEquals(array(1 => 1, 3 => 2, 2 => 3, 7 => 4, 4 => 5, 5 => 6, 9 => 7, 6 => 8), $newnames);
}
$graph3->add_node(3, 4, 4, '+0.1', '-0.1');
$graph3->add_node(4, null, null, '+0.1', '-0.1');
$graph4 = new stack_abstract_graph();
$graph4->add_node(1, 3, 2, '=1', '=0');
$graph4->add_node(2, 4, 4, '+0.1', '-0.1');
$graph4->add_node(3, 4, 4, '+0.1', '-0.1');
$graph4->add_node(4, null, null, '+0.1', '-0.1');
$graph5 = new stack_abstract_graph();
$graph5->add_node(1, 7, 2, '=1', '=0');
$graph5->add_node(2, 7, 3, '+0.1', '-0.1');
$graph5->add_node(3, 7, 4, '+0.1', '-0.1');
$graph5->add_node(4, 7, 5, '+0.1', '-0.1');
$graph5->add_node(5, 7, 6, '+0.1', '-0.1');
$graph5->add_node(6, 7, 7, '+0.1', '-0.1');
$graph5->add_node(7, null, null, '+0.1', '-0.1');
$graph6 = new stack_abstract_graph();
$graph6->add_node(7, 10, 8, '=1', '=0');
$graph6->add_node(8, null, 9, '+0.1', '-0.1');
$graph6->add_node(9, 10, 10, '+0.1', '-0.1');
$graph6->add_node(10, null, null, '+0.1', '-0.1');
$examples = array($broken, $broken2, $tree, $tree2, $tree3, $graph, $graph2, $graph3, $graph4, $graph5, $graph6);
foreach ($examples as $example) {
$example->layout();
}
echo $OUTPUT->header();
echo $OUTPUT->heading('Example graphs');
$i = 0;
foreach ($examples as $example) {
echo stack_abstract_graph_svg_renderer::render($example, 'example' . $i++);
}
echo $OUTPUT->footer();
public function save_question_options($fromform)
{
global $DB;
$context = $fromform->context;
parent::save_question_options($fromform);
$options = $DB->get_record('qtype_stack_options', array('questionid' => $fromform->id));
if (!$options) {
$options = new stdClass();
$options->questionid = $fromform->id;
$options->questionvariables = '';
$options->specificfeedback = '';
$options->prtcorrect = '';
$options->prtpartiallycorrect = '';
$options->prtincorrect = '';
$options->id = $DB->insert_record('qtype_stack_options', $options);
}
$options->questionvariables = $fromform->questionvariables;
$options->specificfeedback = $this->import_or_save_files($fromform->specificfeedback, $context, 'qtype_stack', 'specificfeedback', $fromform->id);
$options->specificfeedbackformat = $fromform->specificfeedback['format'];
$options->questionnote = $fromform->questionnote;
$options->questionsimplify = $fromform->questionsimplify;
$options->assumepositive = $fromform->assumepositive;
$options->prtcorrect = $this->import_or_save_files($fromform->prtcorrect, $context, 'qtype_stack', 'prtcorrect', $fromform->id);
$options->prtcorrectformat = $fromform->prtcorrect['format'];
$options->prtpartiallycorrect = $this->import_or_save_files($fromform->prtpartiallycorrect, $context, 'qtype_stack', 'prtpartiallycorrect', $fromform->id);
$options->prtpartiallycorrectformat = $fromform->prtpartiallycorrect['format'];
$options->prtincorrect = $this->import_or_save_files($fromform->prtincorrect, $context, 'qtype_stack', 'prtincorrect', $fromform->id);
$options->prtincorrectformat = $fromform->prtincorrect['format'];
$options->multiplicationsign = $fromform->multiplicationsign;
$options->sqrtsign = $fromform->sqrtsign;
$options->complexno = $fromform->complexno;
$options->inversetrig = $fromform->inversetrig;
$options->matrixparens = $fromform->matrixparens;
$options->variantsselectionseed = $fromform->variantsselectionseed;
$DB->update_record('qtype_stack_options', $options);
$inputnames = stack_utils::extract_placeholders($fromform->questiontext, 'input');
$inputs = $DB->get_records('qtype_stack_inputs', array('questionid' => $fromform->id), '', 'name, id, questionid');
$questionhasinputs = false;
foreach ($inputnames as $inputname) {
if (array_key_exists($inputname, $inputs)) {
$input = $inputs[$inputname];
unset($inputs[$inputname]);
} else {
$input = new stdClass();
$input->questionid = $fromform->id;
$input->name = $inputname;
$input->options = '';
$input->id = $DB->insert_record('qtype_stack_inputs', $input);
}
$input->type = $fromform->{$inputname . 'type'};
$input->tans = $fromform->{$inputname . 'modelans'};
$input->boxsize = $fromform->{$inputname . 'boxsize'};
$input->strictsyntax = $fromform->{$inputname . 'strictsyntax'};
$input->insertstars = $fromform->{$inputname . 'insertstars'};
$input->syntaxhint = $fromform->{$inputname . 'syntaxhint'};
$input->forbidwords = $fromform->{$inputname . 'forbidwords'};
$input->allowwords = $fromform->{$inputname . 'allowwords'};
$input->forbidfloat = $fromform->{$inputname . 'forbidfloat'};
$input->requirelowestterms = $fromform->{$inputname . 'requirelowestterms'};
$input->checkanswertype = $fromform->{$inputname . 'checkanswertype'};
$input->mustverify = $fromform->{$inputname . 'mustverify'};
$input->showvalidation = $fromform->{$inputname . 'showvalidation'};
$input->options = $fromform->{$inputname . 'options'};
$questionhasinputs = true;
$DB->update_record('qtype_stack_inputs', $input);
}
if ($inputs) {
list($test, $params) = $DB->get_in_or_equal(array_keys($inputs));
$params[] = $fromform->id;
$DB->delete_records_select('qtype_stack_inputs', 'name ' . $test . ' AND questionid = ?', $params);
}
if (!$questionhasinputs) {
// A question with no inputs is an information item.
$DB->set_field('question', 'length', 0, array('id' => $fromform->id));
}
$prtnames = stack_utils::extract_placeholders($fromform->questiontext . $options->specificfeedback, 'feedback');
$prts = $DB->get_records('qtype_stack_prts', array('questionid' => $fromform->id), '', 'name, id, questionid');
foreach ($prtnames as $prtname) {
if (array_key_exists($prtname, $prts)) {
$prt = $prts[$prtname];
unset($prts[$prtname]);
} else {
$prt = new stdClass();
$prt->questionid = $fromform->id;
$prt->name = $prtname;
$prt->feedbackvariables = '';
$prt->firstnodename = 0;
$prt->id = $DB->insert_record('qtype_stack_prts', $prt);
}
// Find the root node of the PRT.
// Otherwise, if an existing question is being edited, and this is an
// existing PRT, base things on the existing question definition.
$graph = new stack_abstract_graph();
foreach ($fromform->{$prtname . 'answertest'} as $nodename => $notused) {
$truenextnode = $fromform->{$prtname . 'truenextnode'}[$nodename];
$falsenextnode = $fromform->{$prtname . 'falsenextnode'}[$nodename];
if ($truenextnode == -1) {
$left = null;
} else {
$left = $truenextnode + 1;
}
if ($falsenextnode == -1) {
$right = null;
} else {
$right = $falsenextnode + 1;
}
$graph->add_node($nodename + 1, $left, $right);
}
$graph->layout();
$roots = $graph->get_roots();
if (count($roots) != 1 || $graph->get_broken_cycles()) {
throw new coding_exception('The PRT ' . $prtname . ' is malformed.');
}
reset($roots);
$firstnode = key($roots) - 1;
$prt->value = $fromform->{$prtname . 'value'};
$prt->autosimplify = $fromform->{$prtname . 'autosimplify'};
$prt->feedbackvariables = $fromform->{$prtname . 'feedbackvariables'};
$prt->firstnodename = $firstnode;
$DB->update_record('qtype_stack_prts', $prt);
$nodes = $DB->get_records('qtype_stack_prt_nodes', array('questionid' => $fromform->id, 'prtname' => $prtname), '', 'nodename, id, questionid, prtname');
foreach ($fromform->{$prtname . 'answertest'} as $nodename => $notused) {
if (array_key_exists($nodename, $nodes)) {
$node = $nodes[$nodename];
unset($nodes[$nodename]);
} else {
$node = new stdClass();
$node->questionid = $fromform->id;
$node->prtname = $prtname;
$node->nodename = $nodename;
$node->truefeedback = '';
$node->falsefeedback = '';
$node->id = $DB->insert_record('qtype_stack_prt_nodes', $node);
}
$node->answertest = $fromform->{$prtname . 'answertest'}[$nodename];
$node->sans = $fromform->{$prtname . 'sans'}[$nodename];
$node->tans = $fromform->{$prtname . 'tans'}[$nodename];
$node->testoptions = $fromform->{$prtname . 'testoptions'}[$nodename];
$node->quiet = $fromform->{$prtname . 'quiet'}[$nodename];
$node->truescoremode = $fromform->{$prtname . 'truescoremode'}[$nodename];
$node->truescore = $fromform->{$prtname . 'truescore'}[$nodename];
$node->truepenalty = $fromform->{$prtname . 'truepenalty'}[$nodename];
$node->truenextnode = $fromform->{$prtname . 'truenextnode'}[$nodename];
$node->trueanswernote = $fromform->{$prtname . 'trueanswernote'}[$nodename];
$node->truefeedback = $this->import_or_save_files($fromform->{$prtname . 'truefeedback'}[$nodename], $context, 'qtype_stack', 'prtnodetruefeedback', $node->id);
$node->truefeedbackformat = $fromform->{$prtname . 'truefeedback'}[$nodename]['format'];
$node->falsescoremode = $fromform->{$prtname . 'falsescoremode'}[$nodename];
$node->falsescore = $fromform->{$prtname . 'falsescore'}[$nodename];
$node->falsepenalty = $fromform->{$prtname . 'falsepenalty'}[$nodename];
$node->falsenextnode = $fromform->{$prtname . 'falsenextnode'}[$nodename];
$node->falseanswernote = $fromform->{$prtname . 'falseanswernote'}[$nodename];
$node->falsefeedback = $this->import_or_save_files($fromform->{$prtname . 'falsefeedback'}[$nodename], $context, 'qtype_stack', 'prtnodefalsefeedback', $node->id);
$node->falsefeedbackformat = $fromform->{$prtname . 'falsefeedback'}[$nodename]['format'];
if ('' === $node->truepenalty) {
$node->truepenalty = null;
}
if ('' === $node->falsepenalty) {
$node->falsepenalty = null;
}
$DB->update_record('qtype_stack_prt_nodes', $node);
}
if ($nodes) {
list($test, $params) = $DB->get_in_or_equal(array_keys($nodes));
$params[] = $fromform->id;
$params[] = $prt->name;
$DB->delete_records_select('qtype_stack_prt_nodes', 'nodename ' . $test . ' AND questionid = ? AND prtname = ?', $params);
}
}
if ($prts) {
list($test, $params) = $DB->get_in_or_equal(array_keys($prts));
$params[] = $fromform->id;
$DB->delete_records_select('qtype_stack_prt_nodes', 'prtname ' . $test . ' AND questionid = ?', $params);
$DB->delete_records_select('qtype_stack_prts', 'name ' . $test . ' AND questionid = ?', $params);
}
$this->save_hints($fromform);
if (isset($fromform->deployedseeds)) {
$DB->delete_records('qtype_stack_deployed_seeds', array('questionid' => $fromform->id));
foreach ($fromform->deployedseeds as $deployedseed) {
$record = new stdClass();
$record->questionid = $fromform->id;
$record->seed = $deployedseed;
$DB->insert_record('qtype_stack_deployed_seeds', $record, false);
}
}
// This is a bit of a hack. If doing 'Make a copy' when saving the
// editing form, then detect that here, and try to copy the question
// tests from the original question.
if (!isset($fromform->testcases) && !empty($fromform->makecopy)) {
$oldquestionid = optional_param('id', 0, PARAM_INT);
if ($oldquestionid) {
$fromform->testcases = $this->load_question_tests($oldquestionid);
}
}
if (isset($fromform->testcases)) {
// If the data includes the defintion of the question tests that there
// should be (i.e. when doing import) then replace the existing set
// of tests with the new one.
$this->save_question_tests($fromform->id, $fromform->testcases);
}
// Irrespective of what else has happened, ensure there is no garbage
// in the database, for example if we delete a PRT, remove the expected
// values for that PRT while leaving the rest of the testcases alone.
list($nametest, $params) = $DB->get_in_or_equal($inputnames, SQL_PARAMS_NAMED, 'input', false, null);
$params['questionid'] = $fromform->id;
$DB->delete_records_select('qtype_stack_qtest_inputs', 'questionid = :questionid AND inputname ' . $nametest, $params);
list($nametest, $params) = $DB->get_in_or_equal($prtnames, SQL_PARAMS_NAMED, 'prt', false, null);
$params['questionid'] = $fromform->id;
$DB->delete_records_select('qtype_stack_qtest_expected', 'questionid = :questionid AND prtname ' . $nametest, $params);
}
foreach ($trees as $qname => $tree) {
$key = json_encode($tree);
$uniquetrees[$key] = $tree;
$qnamesused[$key][] = $qname;
if (array_key_exists($key, $frequency)) {
$frequency[$key] += 1;
} else {
$frequency[$key] = 1;
}
}
arsort($frequency);
echo $OUTPUT->header();
$i = 0;
foreach ($frequency as $key => $count) {
$uniquetree = $uniquetrees[$key];
$tree = new stack_abstract_graph();
foreach ($uniquetree as $node => $branches) {
list($left, $right) = $branches;
if ($left == -1) {
$left = null;
} else {
$left += 1;
}
if ($right == -1) {
$right = null;
} else {
$right += 1;
}
$tree->add_node($node + 1, $left, $right);
}
reset($uniquetree);
/**
* When restoring old data, that does not have the essay options information
* in the XML, supply defaults.
*/
protected function after_execute_question()
{
global $DB;
$prtswithoutfirstnode = $DB->get_records('qtype_stack_prts', array('firstnodename' => -1), '', 'id, questionid, name');
foreach ($prtswithoutfirstnode as $prt) {
$nodes = $DB->get_records('qtype_stack_prt_nodes', array('questionid' => $prt->questionid, 'prtname' => $prt->name), '', 'nodename, truenextnode, falsenextnode');
// Find the root node of the PRT.
// Otherwise, if an existing question is being edited, and this is an
// existing PRT, base things on the existing question definition.
$graph = new stack_abstract_graph();
foreach ($nodes as $node) {
if ($node->truenextnode == -1) {
$left = null;
} else {
$left = $node->truenextnode + 1;
}
if ($node->falsenextnode == -1) {
$right = null;
} else {
$right = $node->falsenextnode + 1;
}
$graph->add_node($node->nodename + 1, $left, $right);
}
$graph->layout();
$roots = $graph->get_roots();
if (count($roots) != 1 || $graph->get_broken_cycles()) {
$questions = $DB->get_records('question', array('id' => $prt->questionid), '', 'name');
$qnames = array();
foreach ($questions as $q) {
$qnames[] = $q->name;
}
if (count($roots) != 1) {
$err = 'abnormal root count: ' . count($roots) . '(<>1)';
} else {
$err = 'broken cycles: ' . implode('.', $graph->get_broken_cycles());
}
throw new coding_exception('The PRT named "' . $prt->name . '" is malformed in question id ' . $prt->questionid . ', question named "' . implode(', ', $qnames) . '". Error reported: ' . $err);
}
reset($roots);
$firstnode = key($roots) - 1;
$DB->set_field('qtype_stack_prts', 'firstnodename', $firstnode, array('id' => $prt->id));
}
}
