Using Binnary Branch Lots Determination

Hallo,

I am using A binnary tree to determine the lotsize depending on the profit of the last three orders. Is it possable that the function OrdersHistoryTotal() doenst work while backtesting? 

         OrderSelect(OrdersHistoryTotal()-1,SELECT_BY_POS,MODE_HISTORY);  
         double P5 = OrderProfit();