prijs berekening virtuemart

/** * This functions interprets the String that is entered in the calc_value_mathop field * The first char is the signum of the function. The more this function can be enhanced * maybe with function that works like operators, the easier it will be to make more complex disount/commission/profit formulas * progressive, nonprogressive and so on. * * @copyright Copyright (c) 2009 VirtueMart Team. All rights reserved. * @author Max Milbers * @param $mathop String reprasentation of the mathematical operation, valid ('+','-','+%','-%') * @param $value float The value that affects the price * @param $currency int the currency which should be used * @param $price float The price to calculate */