MQL4 and MQL5 Programming Articles

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Study the MQL5 language for programming trading strategies in numerous published articles mostly written by you - the community members. The articles are grouped into categories to help you quicker find answers to any questions related to programming: Integration, Tester, Trading Strategies, etc.

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Better Programmer (Part 03): Give Up doing these 5 things to become a successful MQL5 Programmer
Better Programmer (Part 03): Give Up doing these 5 things to become a successful MQL5 Programmer

Better Programmer (Part 03): Give Up doing these 5 things to become a successful MQL5 Programmer

This is the must-read article for anyone wanting to improve their programming career. This article series is aimed at making you the best programmer you can possibly be, no matter how experienced you are. The discussed ideas work for MQL5 programming newbies as well as professionals.
Trend-Hunting
Trend-Hunting

Trend-Hunting

The article describes an algorithm of volume increase of a profit trade. Its implementation using MQL4 means is presented in the article.
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Automating Trading Strategies in MQL5 (Part 30): Creating a Price Action AB-CD Harmonic Pattern with Visual Feedback

Automating Trading Strategies in MQL5 (Part 30): Creating a Price Action AB-CD Harmonic Pattern with Visual Feedback

In this article, we develop an AB=CD Pattern EA in MQL5 that identifies bullish and bearish AB=CD harmonic patterns using pivot points and Fibonacci ratios, executing trades with precise entry, stop loss, and take-profit levels. We enhance trader insight with visual feedback through chart objects.
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MQL5 Wizard Techniques you should know (Part 48): Bill Williams Alligator

MQL5 Wizard Techniques you should know (Part 48): Bill Williams Alligator

The Alligator Indicator, which was the brain child of Bill Williams, is a versatile trend identification indicator that yields clear signals and is often combined with other indicators. The MQL5 wizard classes and assembly allow us to test a variety of signals on a pattern basis, and so we consider this indicator as well.
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Creating an EA that works automatically (Part 05): Manual triggers (II)

Creating an EA that works automatically (Part 05): Manual triggers (II)

Today we'll see how to create an Expert Advisor that simply and safely works in automatic mode. At the end of the previous article, I suggested that it would be appropriate to allow manual use of the EA, at least for a while.
Testing Visualization: Trade History
Testing Visualization: Trade History

Testing Visualization: Trade History

The article describes the possibilities of convenient viewing the trade history when visualizing tests. Starting from build 196, MetaTrader 4 Client Terminal offers testing visualization function. It allows controlling the Expert Advisors' testing on a brand new level. Now, the trading programmer can watch every action of his or her Expert Advisor checking its operation on history!
Graphical Control of External Parameters of Indicators
Graphical Control of External Parameters of Indicators

Graphical Control of External Parameters of Indicators

External variables of indicators are controlled using a special window where parameters can be changed and the indicator is then run again. The obvious inconvenience of these manipulations has given rise to the need for displaying the required parameters on the screen and controlling the indicator graphically.
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Multiple indicators on one chart (Part 05): Turning MetaTrader 5 into a RAD system (I)

Multiple indicators on one chart (Part 05): Turning MetaTrader 5 into a RAD system (I)

There are a lot of people who do not know how to program but they are quite creative and have great ideas. However, the lack of programming knowledge prevents them from implementing these ideas. Let's see together how to create a Chart Trade using the MetaTrader 5 platform itself, as if it were an IDE.
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Data Science and Machine Learning (Part 12): Can Self-Training Neural Networks Help You Outsmart the Stock Market?

Data Science and Machine Learning (Part 12): Can Self-Training Neural Networks Help You Outsmart the Stock Market?

Are you tired of constantly trying to predict the stock market? Do you wish you had a crystal ball to help you make more informed investment decisions? Self-trained neural networks might be the solution you've been looking for. In this article, we explore whether these powerful algorithms can help you "ride the wave" and outsmart the stock market. By analyzing vast amounts of data and identifying patterns, self-trained neural networks can make predictions that are often more accurate than human traders. Discover how you can use this cutting-edge technology to maximize your profits and make smarter investment decisions.
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How to create a custom True Strength Index indicator using MQL5

How to create a custom True Strength Index indicator using MQL5

Here is a new article about how to create a custom indicator. This time we will work with the True Strength Index (TSI) and will create an Expert Advisor based on it.
Interview with Leonid Velichkovsky: "The Biggest Myth about Neural Networks is Super-Profitability" (ATC 2010)
Interview with Leonid Velichkovsky: "The Biggest Myth about Neural Networks is Super-Profitability" (ATC 2010)

Interview with Leonid Velichkovsky: "The Biggest Myth about Neural Networks is Super-Profitability" (ATC 2010)

The hero of our interview Leonid Velichkovski (LeoV) has already participated in Automated Trading Championships. In 2008, his multicurrency neural network was like a bright flash in the sky, earning $110,000 in a certain moment, but eventually fell victim to its own aggressive money management. Two years ago, in his interview Leonid share his own trading experience and told us about the features of his Expert Advisor. On the eve of the ATC 2010, Leonid talks about the most common myths and misconceptions associated with neural networks.
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Introduction to MQL5 (Part 9): Understanding and Using Objects in MQL5

Introduction to MQL5 (Part 9): Understanding and Using Objects in MQL5

Learn to create and customize chart objects in MQL5 using current and historical data. This project-based guide helps you visualize trades and apply MQL5 concepts practically, making it easier to build tools tailored to your trading needs.
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Classification models in the Scikit-Learn library and their export to ONNX

Classification models in the Scikit-Learn library and their export to ONNX

In this article, we will explore the application of all classification models available in the Scikit-Learn library to solve the classification task of Fisher's Iris dataset. We will attempt to convert these models into ONNX format and utilize the resulting models in MQL5 programs. Additionally, we will compare the accuracy of the original models with their ONNX versions on the full Iris dataset.
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Population optimization algorithms: Bacterial Foraging Optimization (BFO)

Population optimization algorithms: Bacterial Foraging Optimization (BFO)

E. coli bacterium foraging strategy inspired scientists to create the BFO optimization algorithm. The algorithm contains original ideas and promising approaches to optimization and is worthy of further study.
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MQL5 Wizard techniques you should know (Part 03): Shannon's Entropy

MQL5 Wizard techniques you should know (Part 03): Shannon's Entropy

Todays trader is a philomath who is almost always looking up new ideas, trying them out, choosing to modify them or discard them; an exploratory process that should cost a fair amount of diligence. These series of articles will proposition that the MQL5 wizard should be a mainstay for traders.
Effective Averaging Algorithms with Minimal Lag: Use in Indicators and Expert Advisors
Effective Averaging Algorithms with Minimal Lag: Use in Indicators and Expert Advisors

Effective Averaging Algorithms with Minimal Lag: Use in Indicators and Expert Advisors

The article describes custom averaging functions of higher quality developed by the author: JJMASeries(), JurXSeries(), JLiteSeries(), ParMASeries(), LRMASeries(), T3Series() and MASeries(). The author considers the hot substitution of these functions in indicators using the call of the SmoothXSeries() function.
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Self Optimizing Expert Advisors in MQL5 (Part 9): Double Moving Average Crossover

Self Optimizing Expert Advisors in MQL5 (Part 9): Double Moving Average Crossover

This article outlines the design of a double moving average crossover strategy that uses signals from a higher timeframe (D1) to guide entries on a lower timeframe (M15), with stop-loss levels calculated from an intermediate risk timeframe (H4). It introduces system constants, custom enumerations, and logic for trend-following and mean-reverting modes, while emphasizing modularity and future optimization using a genetic algorithm. The approach allows for flexible entry and exit conditions, aiming to reduce signal lag and improve trade timing by aligning lower-timeframe entries with higher-timeframe trends.
Graphics in DoEasy library (Part 90): Standard graphical object events. Basic functionality
Graphics in DoEasy library (Part 90): Standard graphical object events. Basic functionality

Graphics in DoEasy library (Part 90): Standard graphical object events. Basic functionality

In this article, I will implement the basic functionality for tracking standard graphical object events. I will start from a double click event on a graphical object.
Technical Analysis: How Do We Analyze?
Technical Analysis: How Do We Analyze?

Technical Analysis: How Do We Analyze?

This article briefly describes the author's opinion on redrawing indicators, multi-timeframe indicators and displaying of quotes with Japanese candlesticks. The article contain no programming specifics and is of a general character.
Selection and navigation utility in MQL5 and MQL4: Adding "homework" tabs and saving graphical objects
Selection and navigation utility in MQL5 and MQL4: Adding "homework" tabs and saving graphical objects

Selection and navigation utility in MQL5 and MQL4: Adding "homework" tabs and saving graphical objects

In this article, we are going to expand the capabilities of the previously created utility by adding tabs for selecting the symbols we need. We will also learn how to save graphical objects we have created on the specific symbol chart, so that we do not have to constantly create them again. Besides, we will find out how to work only with symbols that have been preliminarily selected using a specific website.
Enhancing the Quality of the Code with the Help of Unit Test
Enhancing the Quality of the Code with the Help of Unit Test

Enhancing the Quality of the Code with the Help of Unit Test

Even simple programs may often have errors that seem to be unbelievable. "How could I create that?" is our first thought when such an error is revealed. "How can I avoid that?" is the second question which comes to our mind less frequently. It is impossible to create absolutely faultless code, especially in big projects, but it is possible to use technologies for their timely detection. The article describes how the MQL4 code quality can be enhanced with the help of the popular Unit Testing method.
Fractal Analysis of Joint Currency Movements
Fractal Analysis of Joint Currency Movements

Fractal Analysis of Joint Currency Movements

How independent are currency quotes? Are their movements coordinated or does the movement of one currency suggest nothing of the movement of another? The article describes an effort to tackle this issue using nonlinear dynamics and fractal geometry methods.
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Category Theory in MQL5 (Part 1)

Category Theory in MQL5 (Part 1)

Category Theory is a diverse and expanding branch of Mathematics which as of yet is relatively uncovered in the MQL community. These series of articles look to introduce and examine some of its concepts with the overall goal of establishing an open library that attracts comments and discussion while hopefully furthering the use of this remarkable field in Traders' strategy development.
CCI indicator. Three transformation steps
CCI indicator. Three transformation steps

CCI indicator. Three transformation steps

In this article, I will make additional changes to the CCI affecting the very logic of this indicator. Moreover, we will be able to see it in the main chart window.
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Introduction to MQL5 (Part 4): Mastering Structures, Classes, and Time Functions

Introduction to MQL5 (Part 4): Mastering Structures, Classes, and Time Functions

Unlock the secrets of MQL5 programming in our latest article! Delve into the essentials of structures, classes, and time functions, empowering your coding journey. Whether you're a beginner or an experienced developer, our guide simplifies complex concepts, providing valuable insights for mastering MQL5. Elevate your programming skills and stay ahead in the world of algorithmic trading!
Prices in DoEasy library (part 61): Collection of symbol tick series
Prices in DoEasy library (part 61): Collection of symbol tick series

Prices in DoEasy library (part 61): Collection of symbol tick series

Since a program may use different symbols in its work, a separate list should be created for each of them. In this article, I will combine such lists into a tick data collection. In fact, this will be a regular list based on the class of dynamic array of pointers to instances of CObject class and its descendants of the Standard library.
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Automating Trading Strategies in MQL5 (Part 15): Price Action Harmonic Cypher Pattern with Visualization

Automating Trading Strategies in MQL5 (Part 15): Price Action Harmonic Cypher Pattern with Visualization

In this article, we explore the automation of the Cypher harmonic pattern in MQL5, detailing its detection and visualization on MetaTrader 5 charts. We implement an Expert Advisor that identifies swing points, validates Fibonacci-based patterns, and executes trades with clear graphical annotations. The article concludes with guidance on backtesting and optimizing the program for effective trading.
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Trend strength and direction indicator on 3D bars

Trend strength and direction indicator on 3D bars

We will consider a new approach to market trend analysis based on three-dimensional visualization and tensor analysis of the market microstructure.
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Developing a trading Expert Advisor from scratch (Part 22): New order system (V)

Developing a trading Expert Advisor from scratch (Part 22): New order system (V)

Today we will continue to develop the new order system. It is not that easy to implement a new system as we often encounter problems which greatly complicate the process. When these problems appear, we have to stop and re-analyze the direction in which we are moving.
Electronic Tables in MQL5
Electronic Tables in MQL5

Electronic Tables in MQL5

The article describes a class of dynamic two-dimensional array that contains data of different types in its first dimension. Storing data in the form of a table is convenient for solving a wide range of problems of arrangement, storing and operation with bound information of different types. The source code of the class that implements the functionality of working with tables is attached to the article.
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Reimagining Classic Strategies (Part 12): EURUSD Breakout Strategy

Reimagining Classic Strategies (Part 12): EURUSD Breakout Strategy

Join us today as we challenge ourselves to build a profitable break-out trading strategy in MQL5. We selected the EURUSD pair and attempted to trade price breakouts on the hourly timeframe. Our system had difficulty distinguishing between false breakouts and the beginning of true trends. We layered our system with filters intended to minimize our losses whilst increasing our gains. In the end, we successfully made our system profitable and less prone to false breakouts.
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Improve Your Trading Charts With Interactive GUI's in MQL5 (Part I): Movable GUI (I)

Improve Your Trading Charts With Interactive GUI's in MQL5 (Part I): Movable GUI (I)

Unleash the power of dynamic data representation in your trading strategies or utilities with our comprehensive guide on creating movable GUI in MQL5. Dive into the core concept of chart events and learn how to design and implement simple and multiple movable GUI on the same chart. This article also explores the process of adding elements to your GUI, enhancing their functionality and aesthetic appeal.
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Build Self Optimizing Expert Advisors in MQL5  (Part 3): Dynamic Trend Following and Mean Reversion Strategies

Build Self Optimizing Expert Advisors in MQL5 (Part 3): Dynamic Trend Following and Mean Reversion Strategies

Financial markets are typically classified as either in a range mode or a trending mode. This static view of the market may make it easier for us to trade in the short run. However, it is disconnected from the reality of the market. In this article, we look to better understand how exactly financial markets move between these 2 possible modes and how we can use our new understanding of market behavior to gain confidence in our algorithmic trading strategies.
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Forex arbitrage trading: A simple synthetic market maker bot to get started

Forex arbitrage trading: A simple synthetic market maker bot to get started

Today we will take a look at my first arbitrage robot — a liquidity provider (if you can call it that) for synthetic assets. Currently, this bot is successfully operating as a module in a large machine learning system, but I pulled up an old Forex arbitrage robot from the cloud, so let's take a look at it and think about what we can do with it today.
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Experiments with neural networks (Part 5): Normalizing inputs for passing to a neural network

Experiments with neural networks (Part 5): Normalizing inputs for passing to a neural network

Neural networks are an ultimate tool in traders' toolkit. Let's check if this assumption is true. MetaTrader 5 is approached as a self-sufficient medium for using neural networks in trading. A simple explanation is provided.
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Custom Indicator Workshop (Part 1): Building the Supertrend Indicator in MQL5

Custom Indicator Workshop (Part 1): Building the Supertrend Indicator in MQL5

Build a non‑repainting Supertrend in MQL5 for MetaTrader 5 from first principles. We use an iATR handle and CopyBuffer for volatility, bind buffers with SetIndexBuffer, and configure plots (DRAWCOLORCANDLES plus two line bands) via PlotIndexSetInteger. The logic updates only on closed bars with EMPTY_VALUE to suppress inactive bands, exposing atrPeriod and atrMultiplier inputs. You get a clean, EA‑ready overlay with documented buffers for strategies and signals.
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Build Self Optimizing Expert Advisors in MQL5 (Part 5): Self Adapting Trading Rules

Build Self Optimizing Expert Advisors in MQL5 (Part 5): Self Adapting Trading Rules

The best practices, defining how to safely us an indicator, are not always easy to follow. Quiet market conditions may surprisingly produce readings on the indicator that do not qualify as a trading signal, leading to missed opportunities for algorithmic traders. This article will suggest a potential solution to this problem, as we discuss how to build trading applications capable of adapting their trading rules to the available market data.
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DoEasy. Controls (Part 13): Optimizing interaction of WinForms objects with the mouse, starting the development of the TabControl WinForms object

DoEasy. Controls (Part 13): Optimizing interaction of WinForms objects with the mouse, starting the development of the TabControl WinForms object

In this article, I will fix and optimize handling the appearance of WinForms objects after moving the mouse cursor away from the object, as well as start the development of the TabControl WinForms object.
Practical Use of the Virtual Private Server (VPS) for Autotrading
Practical Use of the Virtual Private Server (VPS) for Autotrading

Practical Use of the Virtual Private Server (VPS) for Autotrading

Autotrading using VPS. This article is intended exceptionally for autotraders and autotrading supporters.
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Price Action Analysis Toolkit Development (Part 17): TrendLoom EA Tool

Price Action Analysis Toolkit Development (Part 17): TrendLoom EA Tool

As a price action observer and trader, I've noticed that when a trend is confirmed by multiple timeframes, it usually continues in that direction. What may vary is how long the trend lasts, and this depends on the type of trader you are, whether you hold positions for the long term or engage in scalping. The timeframes you choose for confirmation play a crucial role. Check out this article for a quick, automated system that helps you analyze the overall trend across different timeframes with just a button click or regular updates.