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'));
}
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_matrix_eigenvalues()
{
$cs = array('A:matrix([7,1,3],[5,-3,4],[5,3,-4])', 'E:first(eigenvalues(A))', 'dt:determinant(A)');
foreach ($cs as $s) {
$s1[] = new stack_cas_casstring($s);
}
$options = new stack_options();
$options->set_option('matrixparens', '(');
$at1 = new stack_cas_session($s1, $options, 0);
$this->assertEquals('[1-sqrt(66),sqrt(66)+1,-2]', $at1->get_value_key('E'));
$this->assertEquals('130', $at1->get_value_key('dt'));
$this->assertEquals('\\left(\\begin{array}{ccc} 7 & 1 & 3 \\\\ 5 & -3 & 4 \\\\ 5 & 3 & -4 \\end{array}\\right)', $at1->get_display_key('A'));
}
/**
* Traverse this node, updating the results array that is used by
* {@link stack_potentialresponse_tree::evaluate_response()}.
*
* @param stack_potentialresponse_tree_state $results to be updated.
* @param int $key the index of this node.
* @param stack_cas_session $cascontext the CAS context that holds all the relevant variables.
* @param stack_options $options
* @return array with two elements, the updated $results and the index of the next node.
*/
public function traverse($results, $key, $cascontext, $options)
{
$errorfree = true;
if ($cascontext->get_errors_key('PRSANS' . $key)) {
$results->_errors .= $cascontext->get_errors_key('PRSANS' . $key);
$results->add_feedback(' ' . stack_string('prtruntimeerror', array('node' => 'PRSANS' . ($key + 1), 'error' => $cascontext->get_errors_key('PRSANS' . $key))));
$errorfree = false;
}
if ($cascontext->get_errors_key('PRTANS' . $key)) {
$results->_errors .= $cascontext->get_errors_key('PRTANS' . $key);
$results->add_feedback(' ' . stack_string('prtruntimeerror', array('node' => 'PRTANS' . ($key + 1), 'error' => $cascontext->get_errors_key('PRTANS' . $key))));
$errorfree = false;
}
if ($cascontext->get_errors_key('PRATOPT' . $key)) {
$results->_errors .= $cascontext->get_errors_key('PRATOPT' . $key);
$results->add_feedback(' ' . stack_string('prtruntimeerror', array('node' => 'PRATOPT' . ($key + 1), 'error' => $cascontext->get_errors_key('PRATOPT' . $key))));
$errorfree = false;
}
if (!$errorfree) {
return -1;
}
$sans = $cascontext->get_value_key('PRSANS' . $key);
$tans = $cascontext->get_value_key('PRTANS' . $key);
$atopts = $cascontext->get_value_key('PRATOPT' . $key);
// If we can't find atopts then they were not processed by the CAS.
// They might still be some in the potential response which do not
// need to be processed.
if (false === $atopts) {
$atopts = null;
}
$nextnode = $this->do_test($sans, $tans, $atopts, $options, $results);
return $nextnode;
}
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'));
}
