public function test_implied_complex_mult3()
{
// This function name ends in an "i", so we need to check *s are not being inserted too many times here.
$s = 'sa:cdf_bernoulli(x,p)';
$at1 = new stack_cas_casstring($s);
$this->assertTrue($at1->get_valid('s', false, 1));
$this->assertEquals('cdf_bernoulli(x,p)', $at1->get_casstring());
}
/**
* Create the CAS context in which we will evaluate this PRT. This contains
* all the question variables, student responses, feedback variables, and all
* the sans, tans and atoptions expressions from all the nodes.
*
* @param stack_cas_session $questionvars the question varaibles.
* @param stack_options $options
* @param array $answers name => value the student response.
* @param int $seed the random number seed.
* @return stack_cas_session initialised with all the expressions this PRT will need.
*/
protected function create_cas_context_for_evaluation($questionvars, $options, $answers, $seed)
{
// Start with the question variables (note that order matters here).
$cascontext = clone $questionvars;
// Set the value of simp from this point onwards.
// If the question has simp:true, but the prt simp:false, then this needs to be done here.
if ($this->simplify) {
$simp = 'true';
} else {
$simp = 'false';
}
$cs = new stack_cas_casstring($simp);
$cs->set_key('simp');
$answervars = array($cs);
// Add the student's responses, but only those needed by this prt.
// Some irrelevant but invalid answers might break the CAS connection.
foreach ($this->get_required_variables(array_keys($answers)) as $name) {
if (array_key_exists($name . '_val', $answers)) {
$cs = new stack_cas_casstring($answers[$name . '_val']);
} else {
$cs = new stack_cas_casstring($answers[$name]);
}
// Validating as teacher at this stage removes the problem of "allowWords" which
// we don't have access to. This effectively allows any words here. But the
// student's answer has already been through validation.
$cs->get_valid('t');
// Setting the key must come after validation.
$cs->set_key($name);
$answervars[] = $cs;
}
$cascontext->add_vars($answervars);
// Add the feedback variables.
$cascontext->merge_session($this->feedbackvariables);
// Add all the expressions from all the nodes.
// Note this approach does not allow for effective guard clauses in the PRT.
// All the inputs to answer tests are evaluated at the start.
foreach ($this->nodes as $key => $node) {
$cascontext->add_vars($node->get_context_variables($key));
}
$cascontext->instantiate();
return $cascontext;
}
public function test_disp_mult_cross()
{
$a2 = array('make_multsgn("cross")', 'b:x*y');
$s2 = array();
foreach ($a2 as $s) {
$cs = new stack_cas_casstring($s);
$cs->get_valid('t');
$s2[] = $cs;
}
$cs2 = new stack_cas_session($s2, null, 0);
$this->assertTrue($cs2->get_valid());
$at1 = new stack_cas_text('@b@', $cs2, 0, 't');
$this->assertTrue($at1->get_valid());
$at1->get_display_castext();
$this->assertEquals($at1->get_display_castext(), '\\(x\\times y\\)');
}
/**
* This is the basic validation of the student's "answer".
* This method is only called if the input is not blank.
*
* Only a few input methods need to modify this method.
* For example, Matrix types have two dimensional contents arrays to loop over.
*
* @param array $contents the content array of the student's input.
* @return array of the validity, errors strings and modified contents.
*/
protected function validate_contents($contents, $forbiddenkeys)
{
$errors = $this->extra_validation($contents);
$valid = !$errors;
// Now validate the input as CAS code.
$modifiedcontents = array();
$allowwords = $this->get_parameter('allowWords', '');
foreach ($contents as $val) {
$answer = new stack_cas_casstring($val);
$answer->get_valid('s', $this->get_parameter('strictSyntax', true), $this->get_parameter('insertStars', 0), $allowwords);
// Ensure student hasn't used a variable name used by the teacher.
if ($forbiddenkeys) {
$answer->check_external_forbidden_words($forbiddenkeys);
}
$forbiddenwords = $this->get_parameter('forbidWords', '');
if ($forbiddenwords) {
$answer->check_external_forbidden_words_literal($forbiddenwords);
}
$modifiedcontents[] = $answer->get_casstring();
$valid = $valid && $answer->get_valid();
$errors .= $answer->get_errors();
}
return array($valid, $errors, $modifiedcontents);
}
/**
* Validates the options, when needed.
*
* @return (bool, string)
* @access public
*/
public function validate_atoptions($opt)
{
if ($this->processcasoptions) {
$cs = new stack_cas_casstring($opt);
return array($cs->get_valid('t'), $cs->get_errors());
}
return array(true, '');
}
/**
* Extract the CAS commands from the string
*
* @access public
* @return bool false if no commands to extract, true if succeeds.
*/
private function extract_cas_commands()
{
// First check contains @s.
$count = preg_match_all('~(?<!@)@(?!@)~', $this->trimmedcastext, $notused);
if ($count == 0) {
// Nothing to do.
return null;
} else {
// Extract the CAS commands.
$temp = stack_utils::all_substring_between($this->trimmedcastext, '@', '@', true);
// Create array of commands matching with their labels.
$i = 0;
$valid = true;
$errors = '';
$cmdarray = array();
$labels = array();
$sessionkeys = array();
if (is_a($this->session, 'stack_cas_session')) {
$sessionkeys = $this->session->get_all_keys();
}
foreach ($temp as $cmd) {
// Trim of surrounding white space and CAS commands.
$cmd = stack_utils::trim_commands($cmd);
$cs = new stack_cas_casstring($cmd);
$cs->get_valid($this->security, $this->syntax, $this->insertstars);
do {
// ... make sure names are not already in use.
$key = 'caschat' . $i;
$i++;
} while (in_array($key, $sessionkeys));
$sesionkeys[] = $key;
$labels[] = $key;
$cs->set_key($key, true);
$cmdarray[] = $cs;
$valid = $valid && $cs->get_valid();
$errors .= $cs->get_errors();
}
if (!$valid) {
$this->valid = false;
$this->errors .= stack_string('stackCas_invalidCommand') . '</br>' . $errors;
}
if (!empty($cmdarray)) {
$newsession = $this->session;
if (null === $newsession) {
$newsession = new stack_cas_session($cmdarray, null, $this->seed);
} else {
$newsession->add_vars($cmdarray);
}
$this->session = $newsession;
// Now replace the commannds with their labels in the text.
$this->trimmedcastext = stack_utils::replace_between($this->trimmedcastext, '@', '@', $labels, true);
}
}
}
/**
* Get the context variables that this node uses, so that they can be
* pre-evaluated prior to transversing the tree.
* @param string $key used to make the variable names unique to this node.
* @return array of stack_cas_casstring
*/
public function get_context_variables($key)
{
$variables = array();
$this->sans->set_key('PRSANS' . $key);
$variables[] = $this->sans;
$this->tans->set_key('PRTANS' . $key);
$variables[] = $this->tans;
if ($this->process_atoptions()) {
$atopts = new stack_cas_casstring($this->atoptions);
$atopts->get_valid('t', false, 0);
$atopts->set_key('PRATOPT' . $key);
$variables[] = $atopts;
}
return $variables;
}
private function validate()
{
if (empty($this->raw) or '' == trim($this->raw)) {
$this->valid = true;
return true;
}
// CAS keyval may not contain @ or $.
if (strpos($this->raw, '@') !== false || strpos($this->raw, '$') !== false) {
$this->errors = stack_string('illegalcaschars');
$this->valid = false;
return false;
}
// Subtle one: must protect things inside strings before we explode.
$str = $this->raw;
$strings = stack_utils::all_substring_strings($str);
foreach ($strings as $key => $string) {
$str = str_replace('"' . $string . '"', '[STR:' . $key . ']', $str);
}
$str = str_replace("\n", ';', $str);
$str = stack_utils::remove_comments($str);
$str = str_replace(';', "\n", $str);
$kvarray = explode("\n", $str);
foreach ($strings as $key => $string) {
foreach ($kvarray as $kkey => $kstr) {
$kvarray[$kkey] = str_replace('[STR:' . $key . ']', '"' . $string . '"', $kstr);
}
}
// 23/4/12 - significant changes to the way keyvals are interpreted. Use Maxima assignmentsm i.e. x:2.
$errors = '';
$valid = true;
$vars = array();
foreach ($kvarray as $kvs) {
$kvs = trim($kvs);
if ('' != $kvs) {
$cs = new stack_cas_casstring($kvs);
$cs->get_valid($this->security, $this->syntax, $this->insertstars);
$vars[] = $cs;
}
}
$this->session->add_vars($vars);
$this->valid = $this->session->get_valid();
$this->errors = $this->session->get_errors();
}
/**
* Create the actual response data. The response data in the test case may
* include expressions in terms of the question variables.
* @param qtype_stack_question $question the question - with $question->session initialised.
* @return array the respones to send to $quba->process_action.
*/
public static function compute_response(qtype_stack_question $question, $inputs)
{
// If the question has simp:false, then the local options should reflect this.
// In this case, test constructors (question authors) will need to explicitly simplify their test case constructions.
$localoptions = clone $question->options;
// Start with the question variables (note that order matters here).
$cascontext = new stack_cas_session(null, $localoptions, $question->seed);
$question->add_question_vars_to_session($cascontext);
// Turn off simplification - we *always* need test cases to be unsimplified, even if the question option is true.
$vars = array();
$cs = new stack_cas_casstring('false');
$cs->set_key('simp');
$vars[] = $cs;
// Now add the expressions we want evaluated.
foreach ($inputs as $name => $value) {
if ('' !== $value) {
$cs = new stack_cas_casstring($value);
if ($cs->get_valid('t')) {
$cs->set_key('testresponse_' . $name);
$vars[] = $cs;
}
}
}
$cascontext->add_vars($vars);
$cascontext->instantiate();
$response = array();
foreach ($inputs as $name => $notused) {
$computedinput = $cascontext->get_value_key('testresponse_' . $name);
// In the case we start with an invalid input, and hence don't send it to the CAS
// We want the response to constitute the raw invalid input.
// This permits invalid expressions in the inputs, and to compute with valid expressions.
if ('' == $computedinput) {
$computedinput = $inputs[$name];
}
if (array_key_exists($name, $question->inputs)) {
$response = array_merge($response, $question->inputs[$name]->maxima_to_response_array($computedinput));
}
}
return $response;
}
public function test_exception_5()
{
$at1 = new stack_cas_casstring("x=1");
$this->setExpectedException('stack_exception');
$at1->get_valid('t', true, 'a');
}
public function test_plot_fail()
{
$cs = array('a:0', 'p:plot(a*x/0,[x,-2,2],[y,-2,2])');
foreach ($cs as $s) {
$cs = new stack_cas_casstring($s);
$cs->get_valid('t');
$s1[] = $cs;
}
$at1 = new stack_cas_session($s1, null, 0);
$at1->instantiate();
$this->assertEquals('0', $at1->get_value_key('a'));
$this->assertEquals('Division by zero.', trim($at1->get_errors_key('p')));
$this->assertFalse(strpos($at1->get_value_key('p'), 'STACK auto-generated plot of 0 with parameters'));
}
public function test_do_test_3()
{
// Nontrivial use of the feeback variables.
// Error in authoring ends up in loop. STACK should bail.
$options = new stack_options();
$seed = 12345;
$questionvars = new stack_cas_keyval('n:3; p:(x+1)^n; ta:p;', $options, $seed, 't');
// Feeback variables.
$cstrings = array('sa1:sans', 'sa2:expand(sans)');
foreach ($cstrings as $s) {
$cs = new stack_cas_casstring($s);
$cs->get_valid('t');
$s1[] = $cs;
}
$feedbackvars = new stack_cas_session($s1, $options, $seed);
$feedbackvars->get_valid();
// Define the tree itself.
$sans = new stack_cas_casstring('sa1');
$sans->get_valid('t');
$tans = new stack_cas_casstring('ta');
$tans->get_valid('t');
$node = new stack_potentialresponse_node($sans, $tans, 'AlgEquiv', '', true);
$node->add_branch(0, '=', 0, '', -1, 'Test 1 false. Look: \\[@(sa1)^2@ \\neq @(sa2)^2@\\]', FORMAT_HTML, '1-0-0');
$node->add_branch(1, '=', 1, '', 1, 'Test 1 true. ', FORMAT_HTML, '1-0-1');
$potentialresponses[] = $node;
$sans = new stack_cas_casstring('sa2');
$sans->get_valid('t');
$tans = new stack_cas_casstring('ta');
$tans->get_valid('t');
$node = new stack_potentialresponse_node($sans, $tans, 'FacForm', 'x', true);
$node->add_branch(0, '-', 0.7, '', 0, 'Test 2 false.', FORMAT_HTML, '1-1-0');
$node->add_branch(1, '+', 1, '', 3, 'Test 2 true', FORMAT_HTML, '1-1-1');
$potentialresponses[] = $node;
$tree = new stack_potentialresponse_tree('', '', true, 5, $feedbackvars, $potentialresponses, 0);
// Some data from students.
$answers = array('sans' => '(x+1)^3');
$result = $tree->evaluate_response($questionvars->get_session(), $options, $answers, $seed);
$this->assertTrue($result->valid);
$this->assertEquals('', $result->errors);
$this->assertEquals(0.3, $result->score);
$this->assertEquals(0, $result->penalty);
$this->assertEquals(2, count($result->feedback));
$this->assertEquals('Test 1 true.', $result->feedback[0]->feedback);
$this->assertEquals('Test 2 false.', $result->feedback[1]->feedback);
$this->assertEquals(array('1-0-1', 'ATFacForm_notfactored.', '1-1-0', '[PRT-CIRCULARITY]=0'), $result->answernotes);
$this->assertEquals(array('sa1', 'ta'), $tree->get_required_variables(array('sa1', 'sa3', 'ta', 'ssa1', 'a1', 't')));
}
public static function make_stack_question_runtime_prt_err()
{
$q = self::make_a_stack_question();
$q->name = 'runtime_prt_err';
$q->questionvariables = "";
$q->questiontext = '<p>Give an example of a system of equations with a unique solution.</p>' . '<p>[[input:ans1]] [[validation:ans1]]</p>';
$q->specificfeedback = '[[feedback:Result]]';
$q->questionnote = '';
$q->inputs['ans1'] = stack_input_factory::make('algebraic', 'ans1', '[x+y=1,x-y=1]', array('boxWidth' => 25));
$feedbackvars = new stack_cas_keyval('', null, 0, 't');
$sans = new stack_cas_casstring('all_listp(equationp,ans1)');
$sans->get_valid('t');
$tans = new stack_cas_casstring('true');
$tans->get_valid('t');
$node0 = new stack_potentialresponse_node($sans, $tans, 'AlgEquiv', '', true);
$node0->add_branch(0, '=', 0, '', -1, 'Your answer should be a list of equations!', FORMAT_HTML, 'Result-0-F');
$node0->add_branch(1, '=', 0, '', 1, 'Your answer is a list of equations.', FORMAT_HTML, 'Result-0-T');
$sans = new stack_cas_casstring('solve(ans1,listofvars(ans1))');
$sans->get_valid('t');
$tans = new stack_cas_casstring('[]');
$tans->get_valid('t');
$node1 = new stack_potentialresponse_node($sans, $tans, 'AlgEquiv', '', true);
$node1->add_branch(0, '=', 0, $q->penalty, -1, 'Your equations have no solution!', FORMAT_HTML, 'Result-1-F');
$node1->add_branch(1, '=', 0, $q->penalty, 2, 'You have some solutions!', FORMAT_HTML, 'Result-1-T');
$sans = new stack_cas_casstring('length(solve(ans1,listofvars(ans1)))');
$sans->get_valid('t');
$tans = new stack_cas_casstring('1');
$tans->get_valid('t');
$node2 = new stack_potentialresponse_node($sans, $tans, 'AlgEquiv', '', true);
$node2->add_branch(0, '=', 0, $q->penalty, -1, 'You should have only one solution.', FORMAT_HTML, 'Result-2-F');
$node2->add_branch(1, '=', 1, $q->penalty, -1, 'Good, you have one solution.', FORMAT_HTML, 'Result-2-T');
$q->prts['Result'] = new stack_potentialresponse_tree('Result', '', true, 1, $feedbackvars->get_session(), array($node0, $node1, $node2), 0);
return $q;
}
protected function initialise_question_instance(question_definition $question, $questiondata)
{
parent::initialise_question_instance($question, $questiondata);
$question->questionvariables = $questiondata->options->questionvariables;
$question->questionnote = $questiondata->options->questionnote;
$question->specificfeedback = $questiondata->options->specificfeedback;
$question->specificfeedbackformat = $questiondata->options->specificfeedbackformat;
$question->prtcorrect = $questiondata->options->prtcorrect;
$question->prtcorrectformat = $questiondata->options->prtcorrectformat;
$question->prtpartiallycorrect = $questiondata->options->prtpartiallycorrect;
$question->prtpartiallycorrectformat = $questiondata->options->prtpartiallycorrectformat;
$question->prtincorrect = $questiondata->options->prtincorrect;
$question->prtincorrectformat = $questiondata->options->prtincorrectformat;
$question->variantsselectionseed = $questiondata->options->variantsselectionseed;
$question->options = new stack_options();
$question->options->set_option('multiplicationsign', $questiondata->options->multiplicationsign);
$question->options->set_option('complexno', $questiondata->options->complexno);
$question->options->set_option('inversetrig', $questiondata->options->inversetrig);
$question->options->set_option('matrixparens', $questiondata->options->matrixparens);
$question->options->set_option('sqrtsign', (bool) $questiondata->options->sqrtsign);
$question->options->set_option('simplify', (bool) $questiondata->options->questionsimplify);
$question->options->set_option('assumepos', (bool) $questiondata->options->assumepositive);
$requiredparams = stack_input_factory::get_parameters_used();
foreach ($questiondata->inputs as $name => $inputdata) {
$allparameters = array('boxWidth' => $inputdata->boxsize, 'strictSyntax' => (bool) $inputdata->strictsyntax, 'insertStars' => (int) $inputdata->insertstars, 'syntaxHint' => $inputdata->syntaxhint, 'forbidWords' => $inputdata->forbidwords, 'allowWords' => $inputdata->allowwords, 'forbidFloats' => (bool) $inputdata->forbidfloat, 'lowestTerms' => (bool) $inputdata->requirelowestterms, 'sameType' => (bool) $inputdata->checkanswertype, 'mustVerify' => (bool) $inputdata->mustverify, 'showValidation' => $inputdata->showvalidation);
$parameters = array();
foreach ($requiredparams[$inputdata->type] as $paramname) {
if ($paramname == 'inputType') {
continue;
}
$parameters[$paramname] = $allparameters[$paramname];
}
// TODO: Do something with $inputdata->options here.
$question->inputs[$name] = stack_input_factory::make($inputdata->type, $inputdata->name, $inputdata->tans, $parameters);
}
$totalvalue = 0;
foreach ($questiondata->prts as $name => $prtdata) {
$totalvalue += $prtdata->value;
}
if ($questiondata->prts && $totalvalue < 1.0E-7) {
throw new coding_exception('There is an error authoring your question. ' . 'The $totalvalue, the marks available for the question, must be positive in question ' . $question->name);
}
foreach ($questiondata->prts as $name => $prtdata) {
$nodes = array();
foreach ($prtdata->nodes as $nodedata) {
$sans = new stack_cas_casstring($nodedata->sans);
$sans->get_valid('t');
$tans = new stack_cas_casstring($nodedata->tans);
$tans->get_valid('t');
if (is_null($nodedata->falsepenalty) || $nodedata->falsepenalty === '') {
$falsepenalty = $questiondata->penalty;
} else {
$falsepenalty = $nodedata->falsepenalty;
}
if (is_null($nodedata->truepenalty) || $nodedata->truepenalty === '') {
$truepenalty = $questiondata->penalty;
} else {
$truepenalty = $nodedata->truepenalty;
}
$node = new stack_potentialresponse_node($sans, $tans, $nodedata->answertest, $nodedata->testoptions, (bool) $nodedata->quiet, '', $nodedata->id);
$node->add_branch(0, $nodedata->falsescoremode, $nodedata->falsescore, $falsepenalty, $nodedata->falsenextnode, $nodedata->falsefeedback, $nodedata->falsefeedbackformat, $nodedata->falseanswernote);
$node->add_branch(1, $nodedata->truescoremode, $nodedata->truescore, $truepenalty, $nodedata->truenextnode, $nodedata->truefeedback, $nodedata->truefeedbackformat, $nodedata->trueanswernote);
$nodes[$nodedata->nodename] = $node;
}
// TODO $feedbackvariables, and $sans, $tans, should probably still be strings
// here, and should be converted to CAS stuff later, only if needed.
if ($prtdata->feedbackvariables) {
$feedbackvariables = new stack_cas_keyval($prtdata->feedbackvariables, null, null, 't');
$feedbackvariables = $feedbackvariables->get_session();
} else {
$feedbackvariables = null;
}
$question->prts[$name] = new stack_potentialresponse_tree($name, '', (bool) $prtdata->autosimplify, $prtdata->value / $totalvalue, $feedbackvariables, $nodes, $prtdata->firstnodename);
}
$question->deployedseeds = array_values($questiondata->deployedseeds);
}
public static function run_test($test)
{
// Note: What we would really like to do is the following.
// $el = stack_input_factory::make('algebraic', 'sans1', 'x');
// $el->set_parameter('insertStars', 1);
// $el->set_parameter('strictSyntax', false);
// $el->set_parameter('sameType', false);
// $cs = $el->validate_student_response($test->rawstring);
// However, we want to pull apart the bits to expose where the various errors occur.
$cs = new stack_cas_casstring($test->rawstring);
$cs->get_valid('s', false, 1);
$cs->set_cas_validation_casstring('sans1', true, true, false, null);
$phpvalid = $cs->get_valid();
if ($phpvalid) {
// Trim off stack_validate_typeless([..], true, true).
$phpcasstring = $cs->get_casstring();
$phpcasstring = substr($phpcasstring, 25);
$phpcasstring = substr($phpcasstring, 0, strlen($phpcasstring) - 12);
$outputphpcasstring = $phpcasstring;
} else {
$phpcasstring = '';
$outputphpcasstring = 'N/A...';
}
$errors = $cs->get_errors();
$passed = true;
if ('php_true' === $test->phpvalid) {
$expected = true;
} else {
$expected = false;
}
if ($phpvalid != $expected) {
$passed = false;
$errors .= ' ' . stack_string('phpvalidatemismatch');
}
if ($phpvalid && $phpcasstring != $test->phpcasstring) {
$passed = false;
$errors .= ' ' . stack_maxima_format_casstring($phpcasstring) . ' \\(\\neq \\) ' . stack_maxima_format_casstring($test->phpcasstring);
}
$casvalid = '';
$caserrors = '';
$casvalue = '';
$casdisplay = '';
if ($cs->get_valid()) {
$options = new stack_options();
$options->set_option('simplify', false);
$session = new stack_cas_session(array($cs), $options, 0);
$session->instantiate();
$session = $session->get_session();
$cs = $session[0];
$caserrors = stack_maxima_translate($cs->get_errors());
$casvalue = stack_maxima_format_casstring($cs->get_value());
if ('cas_true' == $test->casvalid) {
$casexpected = true;
} else {
$casexpected = false;
}
if ('' == $cs->get_value()) {
$casvalid = false;
} else {
$casvalid = true;
}
if ($casexpected != $casvalid) {
$passed = false;
$caserrors .= ' ' . stack_string('casvalidatemismatch');
}
$casdisplay = $cs->get_display();
}
$answernote = $cs->get_answernote();
if ($answernote != $test->ansnotes) {
$passed = false;
$errors .= ' ' . stack_string('ansnotemismatch');
}
return array($passed, $phpvalid, $phpcasstring, $errors, $casvalid, $caserrors, $casdisplay, $casvalue, $answernote);
}
public function do_test()
{
$this->atmark = 1;
$anotes = array();
// Note that in casting to an integer we are lucky here.
// Non-integer strings get cast to zero, which is invalid anyway....
$atestops = (int) $this->atoption;
if (!is_int($atestops) or $atestops <= 0) {
$this->aterror = 'TEST_FAILED';
$this->atfeedback = stack_string('TEST_FAILED', array('errors' => ''));
$this->atfeedback .= stack_string('ATNumDecPlaces_OptNotInt', array('opt' => $this->atoption));
$this->atansnote = 'ATNumDecPlaces_STACKERROR_Option.';
$this->atmark = 0;
$this->atvalid = false;
return null;
}
$commands = array($this->sanskey, $this->tanskey, (string) $this->atoption);
foreach ($commands as $com) {
$cs = new stack_cas_casstring($com);
if (!$cs->get_valid('t', true, 0)) {
$this->aterror = 'TEST_FAILED';
$this->atfeedback = stack_string('TEST_FAILED', array('errors' => ''));
$this->atfeedback .= stack_string('AT_InvalidOptions', array('errors' => $cs->get_errors()));
$this->atansnote = 'ATNumDecPlaces_STACKERROR_Option.';
$this->atmark = 0;
$this->atvalid = false;
return null;
}
}
// Check that the first expression is a floating point number,
// with the right number of decimal places.
$sans = explode('.', $this->sanskey);
if (2 === count($sans)) {
if ($atestops != strlen($sans[1])) {
$this->atfeedback .= stack_string('ATNumDecPlaces_Wrong_DPs');
$anotes[] = 'ATNumDecPlaces_Wrong_DPs (' . strlen($sans[1]) . ' <> ' . $atestops . ')';
$this->atmark = 0;
} else {
$anotes[] = 'ATNumDecPlaces_Correct';
}
} else {
// No '.' found.
$this->atfeedback .= stack_string('ATNumDecPlaces_NoDP');
$anotes[] = 'ATNumDecPlaces_NoDP';
$this->atmark = 0;
}
// Check that the two numbers evaluate to the same value.
$cascommands = array();
$cascommands[] = "caschat2:ev({$this->atoption},simp)";
$cascommands[] = "caschat0:ev(float(round(10^caschat2*{$this->sanskey})/10^caschat2),simp)";
$cascommands[] = "caschat1:ev(float(round(10^caschat2*{$this->tanskey})/10^caschat2),simp)";
$cascommands[] = "caschat3:ev(second(ATAlgEquiv(caschat0,caschat1)),simp)";
$cts = array();
foreach ($cascommands as $com) {
$cs = new stack_cas_casstring($com);
$cs->get_valid('t', true, 0);
$cts[] = $cs;
}
$session = new stack_cas_session($cts, null, 0);
$session->instantiate();
if ('' != $session->get_errors_key('caschat0')) {
$this->aterror = 'TEST_FAILED';
$this->atfeedback = stack_string('TEST_FAILED', array('errors' => $session->get_errors_key('caschat0')));
$anotes[] = 'ATNumDecPlaces_STACKERROR_SAns';
$this->atansnote = implode('. ', $anotes) . '.';
$this->atmark = 0;
$this->atvalid = false;
return null;
}
if ('' != $session->get_errors_key('caschat1')) {
$this->aterror = 'TEST_FAILED';
$this->atfeedback = stack_string('TEST_FAILED', array('errors' => $session->get_errors_key('caschat1')));
$anotes[] = 'ATNumDecPlaces_STACKERROR_TAns';
$this->atansnote = implode('. ', $anotes) . '.';
$this->atmark = 0;
$this->atvalid = false;
return null;
}
if ('' != $session->get_errors_key('caschat2')) {
$this->aterror = 'TEST_FAILED';
$this->atfeedback = stack_string('TEST_FAILED', array('errors' => ''));
$this->atfeedback .= stack_string('AT_InvalidOptions', array('errors' => $session->get_errors_key('caschat2')));
$anotes[] = 'ATNumDecPlaces_STACKERROR_Options.';
$this->atansnote = implode('. ', $anotes) . '.';
$this->atmark = 0;
$this->atvalid = false;
return null;
}
if ($session->get_value_key('caschat3') == 'true') {
// Note, we only want the mark to *stay* at 1.
$this->atmark *= 1;
$anotes[] = 'ATNumDecPlaces_Equiv';
} else {
$this->atmark = 0;
$anotes[] = 'ATNumDecPlaces_Not_equiv';
}
$this->atansnote = implode('. ', $anotes) . '.';
if ($this->atmark) {
return true;
}
return false;
}
public function test_ordergreat()
{
$cs = array('ordergreat(i,j,k)', 'p:matrix([-7],[2],[-3])', 'q:matrix([i],[j],[k])', 'v:dotproduct(p,q)');
foreach ($cs as $s) {
$cs = new stack_cas_casstring($s);
$cs->get_valid('t');
$s1[] = $cs;
}
$at1 = new stack_cas_session($s1, null, 0);
$at1->instantiate();
// There has been a subtle change to associativity in Maxima 5.37.0.
$this->assertEquals('-7\\cdot i+2\\cdot j-3\\cdot k', $at1->get_display_key('v'));
}
/**
* Validate all the maxima code in the question.
*
* This is done last, and separate from the other validation for two reasons:
* 1. The rest of the validation is organised to validate the form in order,
* to match the way the form is defined. Here we need to validate in the
* order that the CAS is evaluated at run-time.
* 2. This is the slowest part of validation, so we only do it at the end if
* everything else is OK.
*
* @param array $errors the errors array that validation is assembling.
* @param array $fromform the submitted data to validate.
* @return array updated $errors array.
*/
protected function validate_question_cas_code($errors, $fromform, $fixingdollars)
{
$keyval = new stack_cas_keyval($fromform['questionvariables'], $this->options, $this->seed, 't');
$keyval->instantiate();
$session = $keyval->get_session();
if ($session->get_errors()) {
$errors['questionvariables'][] = $session->get_errors();
return $errors;
}
// Instantiate all text fields and look for errors.
$castextfields = array('questiontext', 'specificfeedback', 'generalfeedback');
foreach ($castextfields as $field) {
$errors = $this->validate_cas_text($errors, $fromform[$field]['text'], $field, $fixingdollars, clone $session);
}
$errors = $this->validate_cas_text($errors, $fromform['questionnote'], 'questionnote', $fixingdollars, clone $session);
// Make a list of all inputs, instantiate it and then look for errors.
$inputs = $this->get_input_names_from_question_text();
$inputvalues = array();
foreach ($inputs as $inputname => $notused) {
$cs = new stack_cas_casstring($inputname . ':' . $fromform[$inputname . 'modelans']);
$cs->get_valid('t');
$inputvalues[] = $cs;
if ($fromform[$inputname . 'options']) {
$cs = new stack_cas_casstring('optionsfor' . $inputname . ':' . $fromform[$inputname . 'options']);
$cs->get_valid('t');
$inputvalues[] = $cs;
}
}
$inputsession = clone $session;
$inputsession->add_vars($inputvalues);
$inputsession->instantiate();
foreach ($inputs as $inputname => $notused) {
if ($inputsession->get_errors_key($inputname)) {
$errors[$inputname . 'modelans'][] = $inputsession->get_errors_key($inputname);
// TODO: Send the acutal value to to input, and ask it to validate it.
// For example, the matrix input type could check that the model answer is a matrix.
}
if ($fromform[$inputname . 'options'] && $inputsession->get_errors_key('optionsfor' . $inputname)) {
$errors[$inputname . 'options'][] = $inputsession->get_errors_key('optionsfor' . $inputname);
}
// else TODO: Send the acutal value to the input, and ask it to validate it.
}
// At this point if we have errors, especially with inputs, there is no point in executing any of the PRTs.
if (!empty($errors)) {
return $errors;
}
// TODO: loop over all the PRTs in a similar manner....
// Remember, to use
// clone $inputsession
// as the base session to have all the teacher's answers instantiated.
// Otherwise we are likley to do illigitimate things to the various inputs.
return $errors;
}
/**
* Once we know the random seed, we can initialise all the other parts of the question.
*/
public function initialise_question_from_seed()
{
// Build up the question session out of all the bits that need to go into it.
// 1. question variables.
$questionvars = new stack_cas_keyval($this->questionvariables, $this->options, $this->seed, 't');
$session = $questionvars->get_session();
// 2. correct answer for all inputs.
$response = array();
foreach ($this->inputs as $name => $input) {
$cs = new stack_cas_casstring($input->get_teacher_answer());
$cs->get_valid('t');
$cs->set_key($name);
$response[$name] = $cs;
}
$session->add_vars($response);
$sessionlength = count($session->get_session());
// 3. CAS bits inside the question text.
$questiontext = $this->prepare_cas_text($this->questiontext, $session);
// 4. CAS bits inside the specific feedback.
$feedbacktext = $this->prepare_cas_text($this->specificfeedback, $session);
// 5. CAS bits inside the question note.
$notetext = $this->prepare_cas_text($this->questionnote, $session);
// 6. The standard PRT feedback.
$prtcorrect = $this->prepare_cas_text($this->prtcorrect, $session);
$prtpartiallycorrect = $this->prepare_cas_text($this->prtpartiallycorrect, $session);
$prtincorrect = $this->prepare_cas_text($this->prtincorrect, $session);
// Now instantiate the session.
$session->instantiate();
if ($session->get_errors()) {
// We throw an exception here because any problems with the CAS code
// up to this point should have been caught during validation when
// the question was edited or deployed.
throw new stack_exception('qtype_stack_question : CAS error when instantiating the session: ' . $session->get_errors($this->user_can_edit()));
}
// Finally, store only those values really needed for later.
$this->questiontextinstantiated = $questiontext->get_display_castext();
$this->specificfeedbackinstantiated = $feedbacktext->get_display_castext();
$this->questionnoteinstantiated = $notetext->get_display_castext();
$this->prtcorrectinstantiated = $prtcorrect->get_display_castext();
$this->prtpartiallycorrectinstantiated = $prtpartiallycorrect->get_display_castext();
$this->prtincorrectinstantiated = $prtincorrect->get_display_castext();
$session->prune_session($sessionlength);
$this->session = $session;
// Allow inputs to update themselves based on the model answers.
$this->adapt_inputs();
}
public function test_ordergreat()
{
$cs = array('ordergreat(i,j,k)', 'p:matrix([-7],[2],[-3])', 'q:matrix([i],[j],[k])', 'v:dotproduct(p,q)');
foreach ($cs as $s) {
$cs = new stack_cas_casstring($s);
$cs->get_valid('t');
$s1[] = $cs;
}
$at1 = new stack_cas_session($s1, null, 0);
$at1->instantiate();
$this->assertEquals('-7*i+2*j-3*k', $at1->get_value_key('v'));
}
public function test_do_test_fail_quiet()
{
$sans = new stack_cas_casstring('ans1');
$tans = new stack_cas_casstring('3*(x+2)');
$tans->get_valid('t');
$node = new stack_potentialresponse_node($sans, $tans, 'FacForm', 'x', true);
$node->add_branch(0, '+', 0.5, '', -1, 'Boo! Your answer should be in factored form, i.e. @factor(ans1)@.', FORMAT_HTML, '1-0-0');
$node->add_branch(1, '=', 2, '', 3, 'Yeah!', FORMAT_HTML, '1-0-1');
$options = new stack_options();
$result = new stack_potentialresponse_tree_state(1, true, 1);
$nextnode = $node->do_test('3*x+6', '3*(x+2)', 'x', $options, $result);
$this->assertEquals(1, count($result->feedback));
$this->assertEquals('Boo! Your answer should be in factored form, i.e. @factor(ans1)@.', $result->feedback[0]->feedback);
$this->assertEquals(1.5, $result->score);
$data = array('factor(ans1)', 'ans1', '3*(x+2)', 'x');
$this->assertEquals($data, $node->get_required_cas_strings());
}