/**
* Returns the best solution for a given pass of a participant
* @return array An associated array containing the best solution
* @access public
*/
public function getBestSolution($solutions)
{
$user_solution = array();
foreach ($solutions as $idx => $solution_value) {
if (preg_match("/^(\\\$v\\d+)\$/", $solution_value["value1"], $matches)) {
$user_solution[$matches[1]] = $solution_value["value2"];
$varObj = $this->getVariable($matches[1]);
$varObj->setValue($solution_value["value2"]);
} else {
if (preg_match("/^(\\\$r\\d+)\$/", $solution_value["value1"], $matches)) {
if (!array_key_exists($matches[1], $user_solution)) {
$user_solution[$matches[1]] = array();
}
$user_solution[$matches[1]]["value"] = $solution_value["value2"];
} else {
if (preg_match("/^(\\\$r\\d+)_unit\$/", $solution_value["value1"], $matches)) {
if (!array_key_exists($matches[1], $user_solution)) {
$user_solution[$matches[1]] = array();
}
$user_solution[$matches[1]]["unit"] = $solution_value["value2"];
}
}
}
}
foreach ($this->getResults() as $result) {
$resVal = $result->calculateFormula($this->getVariables(), $this->getResults(), parent::getId(), false);
if (is_object($result->getUnit())) {
$user_solution[$result->getResult()]["unit"] = $result->getUnit()->getId();
$user_solution[$result->getResult()]["value"] = $resVal;
} else {
if ($result->getUnit() == NULL) {
$unit_factor = 1;
// there is no fix result_unit, any "available unit" is accepted
$available_units = $result->getAvailableResultUnits(parent::getId());
$result_name = $result->getResult();
if ($available_units[$result_name] != NULL) {
$check_unit = in_array($user_solution[$result_name]['unit'], $available_units[$result_name]);
}
if ($check_unit == true) {
//get unit-factor
$unit_factor = assFormulaQuestionUnit::lookupUnitFactor($user_solution[$result_name]['unit']);
$user_solution[$result->getResult()]["value"] = round(ilMath::_div($resVal, $unit_factor), 55);
}
}
}
if ($result->getResultType() == assFormulaQuestionResult::RESULT_CO_FRAC || $result->getResultType() == assFormulaQuestionResult::RESULT_FRAC) {
$value = assFormulaQuestionResult::convertDecimalToCoprimeFraction($resVal);
if (is_array($value)) {
$frac_helper = $value[1];
$value = $value[0];
}
$user_solution[$result->getResult()]["value"] = $value;
$user_solution[$result->getResult()]["frac_helper"] = $frac_helper;
} elseif ($result->getPrecision() > 0) {
$user_solution[$result->getResult()]["value"] = round($resVal, $result->getPrecision());
} else {
$user_solution[$result->getResult()]["value"] = round($resVal);
}
}
return $user_solution;
}
public static function _sub($left_operand, $right_operand, $scale = 50)
{
if (function_exists("bcsub")) {
return bcsub(ilMath::exp2dec($left_operand), ilMath::exp2dec($right_operand), $scale);
} else {
$res = $left_operand - $right_operand;
if (is_numeric($scale)) {
$res = round($res, $scale);
}
return $res;
}
}
/**
* @param $fNumber
* @return string
* function fixes problem which occur when locale ist set to de_DE for example,
* because bc* function expecting strings
*/
private static function bcconv($fNumber)
{
$fNumber = ilMath::exp2dec($fNumber);
$locale_info = localeconv();
if ($locale_info["decimal_point"] != ".") {
$sAppend = '';
$iDecimals = ini_get('precision') - floor(log10(abs($fNumber)));
if (0 > $iDecimals) {
$fNumber *= pow(10, $iDecimals);
$sAppend = str_repeat('0', -$iDecimals);
$iDecimals = 0;
}
return number_format($fNumber, $iDecimals, '.', '') . $sAppend;
}
return $fNumber;
}
function getBaseValue()
{
if (!is_object($this->getUnit())) {
return $this->value;
} else {
include_once "./Services/Math/classes/class.ilMath.php";
return ilMath::_mul($this->value, $this->getUnit()->getFactor());
}
}
public function getRangeMaxBase()
{
if (is_numeric($this->getRangeMax())) {
if (is_object($this->getUnit())) {
include_once "./Services/Math/classes/class.ilMath.php";
return ilMath::_mul($this->getRangeMax(), $this->getUnit()->getFactor(), 100);
}
}
return $this->getRangeMax();
}
function pfx($tokens, $vars = array())
{
if ($tokens == false) {
return false;
}
$stack = new EvalMathStack();
foreach ($tokens as $token) {
// nice and easy
// if the token is a binary operator, pop two values off the stack, do the operation, and push the result back on
if (in_array($token, array('+', '-', '*', '/', '^'))) {
if (is_null($op2 = $stack->pop())) {
return $this->trigger("internal error");
}
if (is_null($op1 = $stack->pop())) {
return $this->trigger("internal error");
}
include_once "class.ilMath.php";
switch ($token) {
case '+':
$stack->push(ilMath::_add($op1, $op2));
break;
case '-':
$stack->push(ilMath::_sub($op1, $op2));
break;
case '*':
$stack->push(ilMath::_mul($op1, $op2));
break;
case '/':
if ($op2 == 0) {
return $this->trigger("division by zero");
}
$stack->push(ilMath::_div($op1, $op2));
break;
case '^':
$stack->push(ilMath::_pow($op1, $op2));
break;
}
// if the token is a unary operator, pop one value off the stack, do the operation, and push it back on
} elseif ($token == "_") {
$stack->push(-1 * $stack->pop());
// if the token is a function, pop arguments off the stack, hand them to the function, and push the result back on
} elseif (preg_match("/^([a-z]\\w*)\\(\$/", $token, $matches)) {
// it's a function!
$fnn = $matches[1];
if (in_array($fnn, $this->fb)) {
// built-in function:
if (is_null($op1 = $stack->pop())) {
return $this->trigger("internal error");
}
$fnn = preg_replace("/^arc/", "a", $fnn);
// for the 'arc' trig synonyms
if ($fnn == 'ln') {
$fnn = 'log';
}
eval('$stack->push(' . $fnn . '($op1));');
// perfectly safe eval()
} elseif (array_key_exists($fnn, $this->f)) {
// user function
// get args
$args = array();
for ($i = count($this->f[$fnn]['args']) - 1; $i >= 0; $i--) {
if (is_null($args[$this->f[$fnn]['args'][$i]] = $stack->pop())) {
return $this->trigger("internal error");
}
}
$stack->push($this->pfx($this->f[$fnn]['func'], $args));
// yay... recursion!!!!
}
// if the token is a number or variable, push it on the stack
} else {
if (is_numeric($token)) {
$stack->push($token);
} elseif (($hex = $this->from_hexbin($token)) !== FALSE) {
$stack->push($hex);
} elseif (array_key_exists($token, $this->v)) {
$stack->push($this->v[$token]);
} elseif (array_key_exists($token, $vars)) {
$stack->push($vars[$token]);
} else {
return $this->trigger("undefined variable '{$token}'");
}
}
}
// when we're out of tokens, the stack should have a single element, the final result
if ($stack->count != 1) {
return $this->trigger("internal error");
}
return $stack->pop();
}
