public function instantiate()
{
if (null === $this->valid) {
$this->validate();
}
if (!$this->valid) {
return false;
}
$this->session->instantiate();
$this->instantiated = true;
}
public function adapt_to_model_answer($teacheranswer)
{
// Work out how big the matrix should be from the INSTANTIATED VALUE of the teacher's answer.
$cs = new stack_cas_casstring('ta:matrix_size(' . $teacheranswer . ')');
$cs->get_valid('t');
$at1 = new stack_cas_session(array($cs), null, 0);
$at1->instantiate();
if ('' != $at1->get_errors()) {
$this->errors = $at1->get_errors();
return;
}
$size = $at1->get_value_key('ta');
$dimensions = explode(',', $size);
$this->height = trim($dimensions[0], '[]');
$this->width = trim($dimensions[1], '[]');
}
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', $at1->get_value_key('v'));
}
/**
*
*
* @return bool
* @access public
*/
public function do_test()
{
if ('' == trim($this->sanskey)) {
$this->aterror = stack_string('TEST_FAILED', array('errors' => stack_string("AT_EmptySA")));
$this->atfeedback = stack_string('TEST_FAILED', array('errors' => stack_string("AT_EmptySA")));
$this->atansnote = $this->casfunction . 'TEST_FAILED:Empty SA.';
$this->atmark = 0;
$this->atvalid = false;
return null;
}
if ('' == trim($this->tanskey)) {
$this->aterror = stack_string('TEST_FAILED', array('errors' => stack_string("AT_EmptyTA")));
$this->atfeedback = stack_string('TEST_FAILED', array('errors' => stack_string("AT_EmptyTA")));
$this->atansnote = $this->casfunction . 'TEST_FAILED:Empty TA.';
$this->atmark = 0;
$this->atvalid = false;
return null;
}
if ($this->processcasoptions) {
if (null == $this->atoption or '' == $this->atoption) {
$this->aterror = 'TEST_FAILED';
$this->atfeedback = stack_string('TEST_FAILED', array('errors' => stack_string("AT_MissingOptions")));
$this->atansnote = 'STACKERROR_OPTION.';
$this->atmark = 0;
$this->atvalid = false;
return null;
} else {
// Validate with teacher privileges, strict syntax & no automatically adding stars.
$ct = new stack_cas_casstring($this->atoption);
if (!$ct->get_valid('t', true, 1)) {
$this->aterror = 'TEST_FAILED';
$this->atfeedback = stack_string('TEST_FAILED', array('errors' => ''));
$this->atfeedback .= stack_string('AT_InvalidOptions', array('errors' => $ct->get_errors()));
$this->atansnote = 'STACKERROR_OPTION.';
$this->atmark = 0;
$this->atvalid = false;
return null;
}
}
$atopt = $this->atoption;
$ta = "[{$this->tanskey},{$atopt}]";
} else {
$ta = $this->tanskey;
}
// Sort out options.
if (null === $this->options) {
$this->options = new stack_options();
}
if (!(null === $this->simp)) {
$this->options->set_option('simplify', $this->simp);
}
$cascommands = array();
$cascommands[] = "STACKSA:{$this->sanskey}";
$cascommands[] = "STACKTA:{$ta}";
$cascommands[] = "result:StackReturn({$this->casfunction}(STACKSA,STACKTA))";
$cts = array();
foreach ($cascommands as $com) {
$cs = new stack_cas_casstring($com);
$cs->get_valid('t', true, 0);
$cts[] = $cs;
}
$session = new stack_cas_session($cts, $this->options, 0);
$session->instantiate();
$this->debuginfo = $session->get_debuginfo();
if ('' != $session->get_errors_key('STACKSA')) {
$this->aterror = 'TEST_FAILED';
$this->atfeedback = stack_string('TEST_FAILED', array('errors' => $session->get_errors_key('STACKSA')));
$this->atansnote = $this->casfunction . '_STACKERROR_SAns.';
$this->atmark = 0;
$this->atvalid = false;
return null;
}
if ('' != $session->get_errors_key('STACKTA')) {
$this->aterror = 'TEST_FAILED';
$this->atfeedback = stack_string('TEST_FAILED', array('errors' => $session->get_errors_key('STACKTA')));
$this->atansnote = $this->casfunction . '_STACKERROR_TAns.';
$this->atmark = 0;
$this->atvalid = false;
return null;
}
$sessionvars = $session->get_session();
$result = $sessionvars[2];
if ('' != $result->get_errors()) {
$this->aterror = 'TEST_FAILED';
if ('' != trim($result->get_feedback())) {
$this->atfeedback = $result->get_feedback();
} else {
$this->atfeedback = stack_string('TEST_FAILED', array('errors' => $result->get_errors()));
}
$this->atansnote = trim($result->get_answernote());
$this->atmark = 0;
$this->atvalid = false;
return null;
}
$this->atansnote = trim($result->get_answernote());
// Convert the Maxima string 'true' to PHP true.
if ('true' == $result->get_value()) {
$this->atmark = 1;
} else {
$this->atmark = 0;
}
$this->atfeedback = $result->get_feedback();
$this->atvalid = $result->get_valid();
if ($this->atmark) {
return true;
} else {
return false;
}
}
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;
}
/**
* Validate any attempts at this question.
*
* @param array $response the student response to the question.
* @param stack_options $options CAS options to use when validating.
* @param string $teacheranswer the teachers answer as a string representation of the evaluated expression.
* @return stack_input_state represents the current state of the input.
*/
public function validate_student_response($response, $options, $teacheranswer, $forbiddenkeys)
{
if (!is_a($options, 'stack_options')) {
throw new stack_exception('stack_input: validate_student_response: options not of class stack_options');
}
$localoptions = clone $options;
// The validation field should always come back through as a single RAW Maxima expression for each input.
if (array_key_exists($this->name . '_val', $response)) {
$validator = $response[$this->name . '_val'];
} else {
$validator = '';
}
$contents = $this->response_to_contents($response);
if (array() == $contents or $this->is_blank_response($contents)) {
return new stack_input_state(self::BLANK, array(), '', '', '', '', '');
}
// This method actually validates any CAS strings etc.
list($valid, $errors, $modifiedcontents) = $this->validate_contents($contents, $forbiddenkeys);
// If we can't get a "displayed value" back from the CAS, show the student their original expression.
$display = stack_maxima_format_casstring($this->contents_to_maxima($contents));
$interpretedanswer = $this->contents_to_maxima($modifiedcontents);
$answer = new stack_cas_casstring($interpretedanswer);
$lvarsdisp = '';
// Send the string to the CAS.
if ($valid) {
if (!$this->get_parameter('sameType')) {
$teacheranswer = null;
}
$singlevarchars = false;
if (2 == $this->get_parameter('insertStars', 0)) {
$singlevarchars = true;
}
// Generate an expression from which we extract the list of variables in the student's answer.
$lvars = new stack_cas_casstring('ev(listofvars(' . $interpretedanswer . '),simp)');
$lvars->get_valid('t', $this->get_parameter('strictSyntax', true), $this->get_parameter('insertStars', 0), $this->get_parameter('allowWords', ''));
$answer->set_cas_validation_casstring($this->name, $this->get_parameter('forbidFloats', false), $this->get_parameter('lowestTerms', false), $singlevarchars, $teacheranswer, $this->get_parameter('allowWords', ''));
$localoptions->set_option('simplify', false);
$session = new stack_cas_session(array($answer, $lvars), $localoptions, 0);
$session->instantiate();
$session = $session->get_session();
$answer = $session[0];
$lvars = $session[1];
$errors = stack_maxima_translate($answer->get_errors());
if ('' != $errors) {
$valid = false;
}
if ('' == $answer->get_value()) {
$valid = false;
} else {
$display = '\\[ ' . $answer->get_display() . ' \\]';
$interpretedanswer = $answer->get_value();
if (!($lvars->get_value() == '[]')) {
$lvarsdisp = '\\( ' . $lvars->get_display() . '\\) ';
}
}
}
$note = $answer->get_answernote();
// Answers may not contain the ? character. CAS-strings may, but answers may not.
// It is very useful for teachers to be able to add in syntax hints.
if (!(strpos($interpretedanswer, '?') === false)) {
$valid = false;
$errors .= stack_string('qm_error');
}
if (!$valid) {
$status = self::INVALID;
} else {
if ($this->get_parameter('mustVerify', true) && $validator != $this->contents_to_maxima($contents)) {
$status = self::VALID;
} else {
$status = self::SCORE;
}
}
return new stack_input_state($status, $contents, $interpretedanswer, $display, $errors, $note, $lvarsdisp);
}
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', $at1->get_display_key('v'));
}
public static function run_test($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 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_remove_comment_fail()
{
$at1 = new stack_cas_keyval("a:1\n /* This is a comment \n b:2\n */\n c:3", null, 123, 's', true, 0);
$this->assertTrue($at1->get_valid());
$a3 = array('a:1', 'c:4');
$s3 = array();
foreach ($a3 as $s) {
$s3[] = new stack_cas_casstring($s);
}
$cs3 = new stack_cas_session($s3, null, 123);
$cs3->instantiate();
$at1->instantiate();
// This looks strange, but the cache layer gives inconsistent results if the first
// of these populates the cache, and the second one uses it.
$this->assertNotEquals($cs3->get_session(), $at1->get_session()->get_session());
}
