require "vendor/autoload.php";

$calculator = new \Z\MathExecutor();

print $calculator->execute("1 + 2 * (2 - (4+10))^2 + sin(10)");

$executor->addFunction('abs', function($arg) {
    return abs($arg);
}, 1);

<?php
namespace MyNamespace;

use Z\Classes\Token\AbstractOperator;

class ModulusToken extends AbstractOperator
{
    /**
     * Regex of this operator
     * @return string
     */
    public static function getRegex()
    {
        return '\%';
    }

    /**
     * Priority of this operator
     * @return int
     */
    public function getPriority()
    {
        return 3;
    }

    /**
     * Associaion of this operator (self::LEFT_ASSOC or self::RIGHT_ASSOC)
     * @return string
     */
    public function getAssociation()
    {
        return self::LEFT_ASSOC;
    }

    /**
     * Execution of this operator
     * @param InterfaceToken[] $stack Stack of tokens
     * @return TokenNumber            Result of execution
     */
    public function execute(&$stack)
    {
        $op2 = array_pop($stack);
        $op1 = array_pop($stack);
        $result = $op1->getValue() % $op2->getValue();

        return new TokenNumber($result);
    }
}

$executor->addOperator('MyNamespace\ModulusToken');

$executor->setVars(array(
    'var1' => 0.15,
    'var2' => 0.22
));

$executor->execute("$var1 + $var2");