### Introduction

In my previous article entitled "Lite_EXPERT2.mqh: Functional Kit for Developers of Expert Advisors", I familiarized the readers with the Lite_EXPERT2.mqh functions. In this article, I will give real Expert Advisor implementation examples that use these functions. I believe, the operation of the trading functions

OpenBuyOrder1_() OpenSellOrder1_() OpenBuyOrder2_() OpenSellOrder2_() OpenBuyLimitOrder1_() OpenBuyStopOrder1_() OpenSellLimitOrder1_() OpenSellStopOrder1_() Make_BuyTrailingStop_() Make_SellTrailingStop_()

is not materially different from the similar functions provided in the Lite_EXPERT1.mqh file.

The initialization of a few more external variables that they contain, is unlikely to cause any confusion (see Exp_0_1.mq4 and Exp_0.mq4, Exp_1.mq4 and EXP_1_1.mq4). So there is absolutely no need to go back to them once again. I will proceed directly to the examples built using the trading functions that use absolute values of price chart levels as external variables for pending orders.

ddOpenBuyOrder1_() dOpenSellOrder1_() dOpenBuyOrder2_() dOpenSellOrder2_() dOpenBuyLimitOrder1_() dOpenBuyStopOrder1_() dOpenSellLimitOrder1_() dOpenSellStopOrder1_() dModifyOpenBuyOrder_() dModifyOpenSellOrder_() dModifyOpenBuyOrderS() dModifyOpenSellOrderS() dMake_BuyTrailingStop_() dMake_SellTrailingStop_()

The trading strategies that will be discussed further in this article are based on the Average True Range indicator, so this is what I am going to start this article with.

### Using the Average True Range Indicator in Mechanical Trading Systems

The Average True Range indicator (hereinafter - ATR or Average True Range) was developed by Welles Wilder and first introduced in his book "New Concepts in Technical Trading Systems" in 1978. This indicator subsequently became quite popular and is still included in many technical analysis software suites. The ATR indicator itself does not indicate current trend directions but provides a graphic image of volatility or activity of the market under consideration.

Essentially, this indicator can be used in mechanical trading systems in two variants:

1. Filtering signals of the trading system for identification of trend and non-trend market conditions.

In this case the trend direction and entry signals are received from other indicators, while the ATR indicator only provides an additional entry condition. Such additional condition can, for example, be the breakout of the average indicator value by the indicator itself. To get the average ATR value, it is convenient to use the signal average line based on ATR.

2. Adaptive pending orders.

The absolute value of this indicator determines the distances from the bar opening price, outside of which strong price fluctuations are very likely to begin. It is therefore very convenient to use these levels for setting pending orders for opening positions and Stop Loss levels. In this case, we have the opportunity to use the ATR indicator to set orders at a certain distance from the price that would adapt to the current market volatility at every deal. A fixed distance set in the real market conditions is seen much like an old army general, always in a state of combat readiness to the war that has long become history. This often results in a much more interesting trading system performance in the real, ever-changing market conditions. In a very much similar way, you can use the ATR distance to move Trailing Stop levels to the price at every bar change.

Now, we can proceed to developing Expert Advisors using the Lite_EXPERT2.mqh file. The best way to do it is to start with the modernization of the Expert Advisors built on the basis of Lite_EXPERT1.mqh in order to give them better flexibility in trading.

### Trading System that Uses Changes in MA Direction as Signals for Market Entry and Exit

I have already provided a detailed description of such a system in my article entitled "Expert Advisors Based on Popular Trading Systems and Alchemy of Trading Robot Optimization" devoted to very basic trading systems.

It is time to make it more complex. An almost similar trading system based on the Lite_EXPERT2.mqh functions is developed in the Exp_1_1.mq4 Expert Advisor (original Exp_1.mq4). We just need to replace fixed Stop Loss and Take Profit with the ones recalculated in ATR units and add the similar Trailing Stop levels that will shift once upon each bar change. This is best implemented in two stages. We first replace the Stop Loss and Take Profit (the Exp_17_A.mq4 Expert Advisor) and after the code is checked for errors and for being in conformity with the selected trading strategy, we add the Trailing Stop levels (the Exp_17.mq4 Expert Advisor). In the article, I will only provide the final version with more detailed descriptions of changes made to the code.

//+X================================================================X+ //| Exp_17.mq4 | //| Copyright © 2009, Nikolay Kositsin | //| Khabarovsk, farria@mail.redcom.ru | //+X================================================================X+ #property copyright "Copyright © 2009, Nikolay Kositsin" #property link "farria@mail.redcom.ru" //+--------------------------------------------------------+ //| INPUT PARAMETERS OF THE EXPERT ADVISOR FOR BUY DEALS | //+--------------------------------------------------------+ extern bool Test_Up = true; // filter of direction of deal calculations extern int Timeframe_Up = 240; extern double Money_Management_Up = 0.1; extern int Length_Up = 4; // depth of smoothing extern int Phase_Up = 100; // parameter varying within the range (-100..+100), impacts the transitional process quality; extern int IPC_Up = 0; extern int ATR_Period_Up = 14; // True Range averaging period extern int LevMinimum_Up = 40; // Minimum value in points below // which pending order values cannot fall extern int STOPLOSS_Up = 100; // Stop Loss expressed as percentage of ATR extern int TAKEPROFIT_Up = 200; // Take Profit expressed as percentage of ATR extern int TRAILINGSTOP_Up = 100; // Trailing Stop expressed as percentage of ATR extern bool ClosePos_Up = true; // permission to forcibly close a position //+--------------------------------------------------------+ //| INPUT PARAMETERS OF THE EXPERT ADVISOR FOR SELL DEALS | //+--------------------------------------------------------+ extern bool Test_Dn = true; // filter of direction of deal calculations extern int Timeframe_Dn = 240; extern double Money_Management_Dn = 0.1; extern int Length_Dn = 4; // depth of smoothing extern int Phase_Dn = 100; // parameter varying within the range (-100..+100), impacts the transitional process quality; extern int IPC_Dn = 0; extern int ATR_Period_Dn = 14; // True Range averaging period extern int LevMinimum_Dn = 40; // Minimum value in points below // which pending order values cannot fall extern int STOPLOSS_Dn = 100; // Stop Loss expressed as percentage of ATR extern int TAKEPROFIT_Dn = 200; // Take Profit expressed as percentage of ATR extern int TRAILINGSTOP_Dn = 100; // Trailing Stop expressed as percentage of ATR extern bool ClosePos_Dn = true; // permission to forcibly close a position //+---------------------------------------------+ //---- declaration of integer variables for the minimum calculation bars int MinBar_Up, MinBar_Dn; //---- declaration of integer variables for chart time frames in seconds int Period_Up, Period_Dn; //---- declaration of floating point variables for pending orders double _STOPLOSS_Up, _TAKEPROFIT_Up, _LevMinimum_Up, _TRAILINGSTOP_Up; double _STOPLOSS_Dn, _TAKEPROFIT_Dn, _LevMinimum_Dn, _TRAILINGSTOP_Dn; //+X================================================================X+ //| Custom Expert functions | //+X================================================================X+ #include <Lite_EXPERT2.mqh> //+X================================================================X+ //| Custom Expert initialization function | //+X================================================================X+ int init() { //---- Checking correctness of the Timeframe_Up variable value TimeframeCheck("Timeframe_Up", Timeframe_Up); //---- Checking correctness of the Timeframe_Dn variable value TimeframeCheck("Timeframe_Dn", Timeframe_Dn); //---- Initialization of variables MinBar_Up = 4 + 39 + 30;// four bars for entry signals + FATL filter length + JMA filter length MinBar_Up = MathMax(MinBar_Up, ATR_Period_Up + 1); MinBar_Dn = 4 + 39 + 30;// four bars for entry signals + FATL filter length + JMA filter length MinBar_Dn = MathMax(MinBar_Dn, ATR_Period_Dn + 1); //---- Period_Up = Timeframe_Up * 60; // chart time frame for long positions in seconds Period_Dn = Timeframe_Dn * 60; // chart time frame for short positions in seconds //---- Conversion of percent to fraction _STOPLOSS_Up = STOPLOSS_Up / 100.0; _TAKEPROFIT_Up = TAKEPROFIT_Up / 100.0; _TRAILINGSTOP_Up = TRAILINGSTOP_Up / 100.0; //---- Conversion of percent to fraction _STOPLOSS_Dn = STOPLOSS_Dn / 100.0; _TAKEPROFIT_Dn = TAKEPROFIT_Dn / 100.0; _TRAILINGSTOP_Dn = TRAILINGSTOP_Dn / 100.0; //---- Conversion of the minimum points to the price distance minimum _LevMinimum_Up = LevMinimum_Up * Point; _LevMinimum_Dn = LevMinimum_Dn * Point; //---- initialization complete return(0); } //+X================================================================X+ //| expert deinitialization function | //+X================================================================X+ int deinit() { //----+ Deleting global variables after testing and optimizations TimeLevelGlobalVariableDel(Symbol(), 1); TimeLevelGlobalVariableDel(Symbol(), 2); //---- Expert Advisor deinitialization complete return(0); //----+ } //+X================================================================X+ //| Custom Expert iteration function | //+X================================================================X+ int start() { //----+ //----+ Declaration of local variables int bar; double Mov[3], dMov12, dMov23, ATR, Level, open; //----+ Declaration of static variables static datetime TradeTimeLevel_Up, TradeTimeLevel_Dn; //---- static bool BUY_Sign, BUY_Stop, SELL_Sign, SELL_Stop; static bool TrailSignal_Up, TrailSignal_Dn; //---- static double dStopLoss_Up, dTakeProfit_Up, dTrailingStop_Up; static double dStopLoss_Dn, dTakeProfit_Dn, dTrailingStop_Dn; //+---------------------------+ //| CODE FOR LONG POSITIONS | //+---------------------------+ if (Test_Up) if (MinBarCheck(Symbol(), Timeframe_Up, MinBar_Up)) { if (IsNewBar(0, Symbol(), Timeframe_Up)) { //----+ Zeroing out trading signals BUY_Sign = false; BUY_Stop = false; //---- Getting the time limit for disabling // the next trading operation TradeTimeLevel_Up = iTime(NULL, Timeframe_Up, 0); if (TradeTimeLevel_Up == 0) return(-1); TradeTimeLevel_Up += Period_Up; //----+ CALCULATING AND LOADING INDICATOR VALUES TO BUFFERS for(bar = 1; bar <= 3; bar++) Mov[bar - 1]= iCustom(NULL, Timeframe_Up, "JFatl", Length_Up, Phase_Up, 0, IPC_Up, 0, bar); //----+ DETERMINING SIGNALS FOR DEALS dMov12 = Mov[0] - Mov[1]; dMov23 = Mov[1] - Mov[2]; //---- Getting a signal for opening a position if (dMov23 < 0) if (dMov12 > 0) BUY_Sign = true; //---- Getting a signal for closing a position if (dMov12 < 0) if (ClosePos_Up) BUY_Stop = true; //----+ CALCULATION OF PENDING ORDERS FOR LONG POSITIONS // Make order calculation only if the trading signal is available if (BUY_Sign) { //---- Getting the initial ATR value ATR = iATR(NULL, Timeframe_Up, ATR_Period_Up, 1); //---- Getting the current price open = iOpen(Symbol(), Timeframe_Up, 0); //---- Calculating the distance to the Stop Loss Level = ATR * _STOPLOSS_Up; //---- Checking the distance to the Stop Loss against the minimum value if (Level < _LevMinimum_Up) Level = _LevMinimum_Up; //---- Determining the absolute Stop Loss value dStopLoss_Up = open - Level; //---- Calculating the distance to the Take Profit Level = ATR * _TAKEPROFIT_Up; //---- Checking the distance to the Take Profit against the minimum value if (Level < _LevMinimum_Up) Level = _LevMinimum_Up; //---- Determining the absolute Take Profit value dTakeProfit_Up = open + Level; //---- Correcting values of pending // orders, given the direction of the trade dGhartVelueCorrect(OP_BUY, dStopLoss_Up); dGhartVelueCorrect(OP_BUY, dTakeProfit_Up); } //----+ CALCULATION OF TRAILING STOPS FOR LONG POSITIONS dTrailingStop_Up = 0; TrailSignal_Up = false; //---- if (TRAILINGSTOP_Up > 0) // Calculate the Trailing Stop only if the necessary position exists if (OrderSelect_(Symbol(), OP_BUY, 1, MODE_TRADES)) // Move Trailing Stop if the position is opened on a non-zero bar if (iBarShift(NULL, Timeframe_Up, OrderOpenTime(), false) > 0) { TrailSignal_Up = true; //---- Getting the initial ATR value ATR = iATR(NULL, Timeframe_Up, ATR_Period_Up, 1); //---- Getting the current price open = iOpen(Symbol(), Timeframe_Up, 0); //---- Calculating the distance to the Stop Loss Level = ATR * _TRAILINGSTOP_Up; //---- Checking the distance to the Stop Loss against the minimum value if (Level < _LevMinimum_Up) Level = _LevMinimum_Up; //---- Getting the absolute Trailing Stop value dTrailingStop_Up = open - Level; //---- Correcting the absolute Trailing Stop value, // given the direction of the trade (for position // modification functions the value of the cmd variable is inverse!) dGhartVelueCorrect(OP_SELL, dTrailingStop_Up); } } //----+ DEAL EXECUTION if (!dOpenBuyOrder1_(BUY_Sign, 1, TradeTimeLevel_Up, Money_Management_Up, 5, dStopLoss_Up, dTakeProfit_Up)) return(-1); //---- if (!CloseBuyOrder1_(BUY_Stop, 1)) return(-1); //---- if (!dMake_BuyTrailingStop_(TrailSignal_Up, 1, TradeTimeLevel_Up, dTrailingStop_Up)) return(-1); } //+---------------------------+ //| CODE FOR SHORT POSITIONS | //+---------------------------+ if (Test_Dn) if (MinBarCheck(Symbol(), Timeframe_Dn, MinBar_Dn)) { if (IsNewBar(1, Symbol(), Timeframe_Dn)) { //----+ Zeroing out trading signals SELL_Sign = false; SELL_Stop = false; //---- Getting the time limit for disabling // the next trading operation TradeTimeLevel_Dn = iTime(NULL, Timeframe_Dn, 0); if (TradeTimeLevel_Dn == 0) return(-1); TradeTimeLevel_Dn += Period_Dn; //----+ CALCULATING AND LOADING INDICATOR VALUES TO BUFFERS for(bar = 1; bar <= 3; bar++) Mov[bar - 1]= iCustom(NULL, Timeframe_Dn, "JFatl", Length_Dn, Phase_Dn, 0, IPC_Dn, 0, bar); //----+ DETERMINING SIGNALS FOR DEALS dMov12 = Mov[0] - Mov[1]; dMov23 = Mov[1] - Mov[2]; //---- Getting a signal for opening a position if (dMov23 > 0) if (dMov12 < 0) SELL_Sign = true; //---- Getting a signal for closing a position if (dMov12 > 0) if (ClosePos_Dn) SELL_Stop = true; //----+ CALCULATION OF PENDING ORDERS FOR SHORT POSITIONS // Make order calculation only if the trading signal is available if (SELL_Sign) { //---- Getting the initial ATR value ATR = iATR(NULL, Timeframe_Dn, ATR_Period_Dn, 1); //---- Getting the current price open = iOpen(Symbol(), Timeframe_Dn, 0); //---- Calculating the distance to the Stop Loss Level = ATR * _STOPLOSS_Dn; //---- Checking the distance to the Stop Loss against the minimum value if (Level < _LevMinimum_Dn) Level = _LevMinimum_Dn; //---- Determining the absolute Stop Loss value dStopLoss_Dn = open + Level; //---- Calculating the distance to the Take Profit Level = ATR * _TAKEPROFIT_Dn; //---- Checking the distance to the Take Profit against the minimum value if (Level < _LevMinimum_Dn) Level = _LevMinimum_Dn; //---- Determining the absolute Take Profit value dTakeProfit_Dn = open - Level; //---- Correcting values of pending orders, given the direction of the trade dGhartVelueCorrect(OP_SELL, dStopLoss_Dn); dGhartVelueCorrect(OP_SELL, dTakeProfit_Dn); } //----+ CALCULATION OF TRAILING STOPS FOR SHORT POSITIONS dTrailingStop_Dn = 0; TrailSignal_Dn = false; //---- if (TRAILINGSTOP_Dn > 0) // Calculate the Trailing Stop only if the necessary position exists if (OrderSelect_(Symbol(), OP_SELL, 2, MODE_TRADES)) // Move Trailing Stop if the position is opened on a non-zero bar if (iBarShift(NULL, Timeframe_Dn, OrderOpenTime(), false) > 0) { TrailSignal_Dn = true; //---- Getting the initial ATR value ATR = iATR(NULL, Timeframe_Dn, ATR_Period_Dn, 1); //---- Getting the current price open = iOpen(Symbol(), Timeframe_Dn, 0); //---- Calculating the distance to the Stop Loss Level = ATR * _TRAILINGSTOP_Dn; //---- Checking the distance to the Stop Loss against the minimum value if (Level < _LevMinimum_Dn) Level = _LevMinimum_Dn; //---- Getting the absolute Trailing Stop value dTrailingStop_Dn = open + Level; //---- Correcting the absolute Trailing Stop value, // given the direction of the trade (for position // modification functions the value of the cmd variable is inverse!) dGhartVelueCorrect(OP_BUY, dTrailingStop_Dn); } } //----+ DEAL EXECUTION if (!dOpenSellOrder1_(SELL_Sign, 2, TradeTimeLevel_Dn, Money_Management_Dn, 5, dStopLoss_Dn, dTakeProfit_Dn)) return(-1); //---- if (!CloseSellOrder1_(SELL_Stop, 2)) return(-1); //---- if (!dMake_SellTrailingStop_(TrailSignal_Dn, 2, TradeTimeLevel_Dn, dTrailingStop_Dn)) return(-1); } return(0); //----+ } //+X----------------------+ <<< The End >>> +-----------------------X+

So, we have a new pair of variables in the block of external variables of the Expert Advisor - ATR_Period_Up and ATR_Period_Dn that can be used to change the ATR indicator values involved in the calculation of pending orders. Now, the logical meaning of values of external variables for Stop Loss, Take Profit and Trailing Stop is somewhat different. These values used to represent relative distance in points from the order to the current price. They now represent percent of the ATR indicator value on the first bar. In other words, to calculate the order, we take percent of the ATR indicator and add it to the value of the zero bar opening price. So the best way to convert percent to the floating point value is to use the init() block of the Expert Advisor where these calculations will be done only once and the calculated values will be saved to the variables declared with a global scope.

Due to the new ATR indicator available, formulas for initialization of the LevMinimum_Up and LevMinimum_Dn variables in the init() block have changed. The start() block of the Expert Advisor features new variables declared as static to store values between the ticks of the terminal. The code for the calculation of pending orders and Trailing Stop levels is arranged into small modules inside the blocks for getting deal signals. Now in order to execute a deal, we use different functions where the value of five is used upon initialization of the Margin_Mode variable as a more logical value in the floating Stop Loss conditions.

To demonstrate the opportunities offered by the use of the IndicatorCounted_() and ReSetAsIndexBuffer() functions, in this Expert Advisor we replaced the custom indicator JFatl.mq4 with the JFATL() function inserted in the code of the Expert Advisor.

bool JFATL(int Number, string symbol, int timeframe, int Length, int Phase, int IPC, double& Buffer[])

The function gets input parameters of the indicator and the Buffer[] array. In case of successful calculation, the function returns true, otherwise false. The array is by reference converted to the indicator buffer analog filled with the JFATL indicator values. In the function, the JJMASeries() function is replaced with JJMASeries1() that does not perform calculations on the zero bar. We have also replaced the PriceSeries() function with the iPriceSeries() function. The indicator initialization block has been moved to the "Zero initialization" block. Please note that the JJMASeries1() function is only used within this function in the Expert Advisor so the Number variable value is not recalculated and is passed to the JJMASeries1() directly. The same applies to the IndicatorCounted_() function.

I have already talked about such replacements of indicators with function in my other articles devoted to this subject: 1, 2, 3. The Expert Advisor that features this replacement is represented by the Exp_17_.mq4 file. We should note the fact that the JMA smoothing algorithm employed in the JFatl.mq4 indicator is quite resource consuming and such replacement of the indicator with the indicator function results in a quite significant optimization speed gain in this Expert Advisor when compared to the previous version. And finally, for the most lazy of you, the same Expert Advisor (Exp_17R.mq4) was developed in such a way that it can contain all the necessary functions within its code, without requiring any additional include files or indicators for its compilation and operation. The operation of all three analogs of this Expert Advisor is identical! Except perhaps the fact that IPC_Up and IPC_Dn variable values in the last Expert Advisor vary within a somewhat smaller range (0-10) due to the lack of calling the Heiken Ashi#.mq4 indicator.

In the forum, you can occasionally see some MQL4 programming gurus frown on the idea of writing such indicator functions, which in their opinion is like putting on your pants by the head. I personally only spend fifteen minutes of my time writing such a function based on a quite easy-to-understand code. So if one can be six times faster when running an optimization marathon with the pants put on that way, I would stick with this option!

**Breakout System for Trading the News**

This version of the trading system has already been provided for your consideration in my article in the form of the Exp_10.mq4 Expert Advisor. The Exp_10_1.mq4 Expert Advisor based on the Lite_EXPERT2.mqh functions is completely analogous. It is slightly more complicated than the original version but much more reliable as it does not get affected by different cases of Expert Advisor, Terminal or Operating System restart. To determine the time after which an open position should be closed, this Expert Advisor uses the TradeTimeLevelCheck() function:

This function returns true after the point of time the value of which was passed as an input parameter to the function for placing pending orders or opening positions. The value as such is obtained by the function from the global variable.

Now we need to change the algorithm of pending order calculation. But in this case, Stop orders should also be dynamically calculated in addition to Stop Loss and Take Profit. Essentially, this does not change anything for us and everything is implemented in the same way. Furthermore, Trailing Stop in the original Expert Advisor works on every tick, while we need to move it at every bar change. The final code of the Expert Advisor (Exp_18.mq4) is certainly not as simple as the original one but the program logic is quite concise and straightforward. Exp_18R.mq4 is a complete analog of the last Expert Advisor implemented in the form of a finished, self-contained file.

### Conclusion

I believe, the Lite_EXPERT2.mqh custom functions are not anything new when compared to the Lite_EXPERT1.mqh functions in terms of programming approach.

They simply enhance programming functionality, while remaining essentially the same in terms of application. So after a careful study of the Lite_EXPERT1.mqh functions, you should not find any difficulty in learning the functionality of Lite_EXPERT2.mqh quickly and easily.

Translated from Russian by MetaQuotes Software Corp.

Original article: https://www.mql5.com/ru/articles/1384

**Attached files**|