double PositionLastClosedPriceOpen(string f_symbol="", // instrument finansowy
                                   int    f_cmd=-1,    // typ pozycji
                                   int    f_magic=-1)  // identyfikator
  {
   if(f_cmd==OP_BUYLIMIT || f_cmd==OP_SELLLIMIT ||
      f_cmd==OP_BUYSTOP  || f_cmd==OP_SELLSTOP)
      return DBL_MAX;
//---
   datetime f_timeClose=0;
   double   f_priceOpen=DBL_MAX;
   for(int i=OrdersHistoryTotal()-1; i>=0; i--)
      if(OrderSelect(i,SELECT_BY_POS,MODE_HISTORY))
         if((f_symbol==OrderSymbol()      || f_symbol=="") &&
            (f_cmd   ==OrderType()        || f_cmd==-1)    &&
            (f_magic ==OrderMagicNumber() || f_magic==-1))
            if(OrderCloseTime()>f_timeClose)
              {
               f_timeClose=OrderCloseTime();
               f_priceOpen=OrderOpenPrice();
              }
   return f_priceOpen;
  }