Two identical trading systems (for long and short deals) based on the VortexIndicator indicator signals that can be configured in different ways within a single EA with an ability to change the volume of a forthcoming trade depending on the results of the previous trades for this trading system. The Expert Advisor is a result of further development of the Exp_VortexIndicator_Duplex trading system, the aim of which was to enable changing of the volume of opened positions.
The following Expert Advisor input blocks have been added for that purpose:
input uint    L_TotalMMTriger=5;    //L number of the last Buy deals to calculate stop loss input uint    L_LossMMTriger=3;    //L number of losing Buy deals to reduce MM input double  L_SmallMM=0.01;      //L Share of a deposit in a deal in case of loss input double  L_MM=0.1;            //L Share of a deposit in a deal during normal trading input MarginMode L_MMMode=LOT;      //L lot setting mode
and
input uint    S_TotalMMTriger=5;    //S number of the last Sell deals to calculate stop loss input uint    S_LossMMTriger=3;    //S number of losing Sell deals to reduce MM input double  S_SmallMM=0.01;      //S Share of a deposit in a deal in case of loss input double  S_MM=0.1;            //S Share of a deposit in a deal during normal trading input MarginMode S_MMMode=LOT;      //S lot setting mode
In case of such inputs and when selecting from the last five trades, three of which are loss-making in a single direction, the EA opens the next trade in the same direction having the volume of 0.01 lot. If there are less than three loss-making trades out of the last five ones, the position volume is 0.1.
For the Expert Advisor to operate, you should place the compiled VortexIndicator.ex5 indicator files to <terminal_data_directory>MQL5Indicators.
The EA default input parameters were used in tests below. Stop Loss and Take Profit were not used in testing.
Fig.1. Examples of deals on the chart with symmetrical settings.
Testing results for 2017 at EURAUD H8:
Fig.2. Testing results chart.