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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The MQL5 Standard Library Explorer (Part 10): Polynomial Regression Channel

The MQL5 Standard Library Explorer (Part 10): Polynomial Regression Channel

Today, we explore another component of ALGLIB, leveraging its mathematical capabilities to develop a Polynomial Regression Channel indicator. By the end of this discussion, you will gain practical insights into indicator development using the MQL5 Standard Library, along with a fully functional, mathematically driven indicator source code.
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Implementing Practical Modules from Other Languages in MQL5 (Part 04): time, date, and datetime modules from Python

Implementing Practical Modules from Other Languages in MQL5 (Part 04): time, date, and datetime modules from Python

Unlike MQL5, Python programming language offers control and flexibility when it comes to dealing with and manipulating time. In this article, we will implement similar modules for better handling of dates and time in MQL5 as in Python.
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Bivariate Copulae in MQL5 (Part 2): Implementing Archimedean copulae in MQL5

Bivariate Copulae in MQL5 (Part 2): Implementing Archimedean copulae in MQL5

In the second installment of the series, we discuss the properties of bivariate Archimedean copulae and their implementation in MQL5. We also explore applying copulae to the development of a simple pairs trading strategy.
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Self Optimizing Expert Advisors in MQL5 (Part 12): Building Linear Classifiers Using Matrix Factorization

Self Optimizing Expert Advisors in MQL5 (Part 12): Building Linear Classifiers Using Matrix Factorization

This article explores the powerful role of matrix factorization in algorithmic trading, specifically within MQL5 applications. From regression models to multi-target classifiers, we walk through practical examples that demonstrate how easily these techniques can be integrated using built-in MQL5 functions. Whether you're predicting price direction or modeling indicator behavior, this guide lays a strong foundation for building intelligent trading systems using matrix methods.
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Developing a Replay System (Part 72): An Unusual Communication (I)

Developing a Replay System (Part 72): An Unusual Communication (I)

What we create today will be difficult to understand. Therefore, in this article I will only talk about the initial stage. Please read this article carefully, it is an important prerequisite before we proceed to the next step. The purpose of this material is purely didactic as we will only study and master the presented concepts, without practical application.
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Matrix Factorization: The Basics

Matrix Factorization: The Basics

Since the goal here is didactic, we will proceed as simply as possible. That is, we will implement only what we need: matrix multiplication. You will see today that this is enough to simulate matrix-scalar multiplication. The most significant difficulty that many people encounter when implementing code using matrix factorization is this: unlike scalar factorization, where in almost all cases the order of the factors does not change the result, this is not the case when using matrices.
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Reimagining Classic Strategies (Part 14): High Probability Setups

Reimagining Classic Strategies (Part 14): High Probability Setups

High probability Setups are well known in our trading community, but regrettably they are not well-defined. In this article, we will aim to find an empirical and algorithmic way of defining exactly what is a high probability setup, identifying and exploiting them. By using Gradient Boosting Trees, we demonstrated how the reader can improve the performance of an arbitrary trading strategy and better communicate the exact job to be done to our computer in a more meaningful and explicit manner.
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Developing a Replay System — Market simulation (Part 07): First improvements (II)

Developing a Replay System — Market simulation (Part 07): First improvements (II)

In the previous article, we made some fixes and added tests to our replication system to ensure the best possible stability. We also started creating and using a configuration file for this system.
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Market Simulation (Part 16): Sockets (X)

Market Simulation (Part 16): Sockets (X)

We are close to completing this challenge. However, before we begin, I want you to try to understand these two articles—this one and the previous one. That way, you will truly understand the next article, in which I will cover exclusively the part related to MQL5 programming. But I will also try to make it understandable. If you do not understand these last two articles, it will be difficult for you to understand the next one, because the material accumulates. The more things there are to do, the more you need to create and understand in order to achieve the goal.
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Neural Network in Practice: Secant Line

Neural Network in Practice: Secant Line

As already explained in the theoretical part, when working with neural networks we need to use linear regressions and derivatives. Why? The reason is that linear regression is one of the simplest formulas in existence. Essentially, linear regression is just an affine function. However, when we talk about neural networks, we are not interested in the effects of direct linear regression. We are interested in the equation that generates this line. We are not that interested in the line created. Do you know the main equation that we need to understand? If not, I recommend reading this article to understanding it.
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Self Optimizing Expert Advisors in MQL5 (Part 12): Building Linear Classifiers Using Matrix Factorization

Self Optimizing Expert Advisors in MQL5 (Part 12): Building Linear Classifiers Using Matrix Factorization

This article explores the powerful role of matrix factorization in algorithmic trading, specifically within MQL5 applications. From regression models to multi-target classifiers, we walk through practical examples that demonstrate how easily these techniques can be integrated using built-in MQL5 functions. Whether you're predicting price direction or modeling indicator behavior, this guide lays a strong foundation for building intelligent trading systems using matrix methods.
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From Novice to Expert: Candlestick Momentum Confirmation for Classic Crossover Strategies

From Novice to Expert: Candlestick Momentum Confirmation for Classic Crossover Strategies

In this article, we refine a moving average crossover strategy with a momentum candle filter and an immediate retracement bar confirmation. When both conditions are met, a pending stop order is placed using a pivot-based stop loss and a 2R take profit. The complete MQL5 Expert Advisor code, finite-state-machine logic, and chart annotations are detailed.
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Building a Hull Moving Average Momentum Oscillator in MQL5

Building a Hull Moving Average Momentum Oscillator in MQL5

This article builds a Hull Moving Average Momentum indicator in MQL5 by combining raw price momentum with Hull MA smoothing. We compute momentum as the close-to-close difference over a user-defined length, form 2×Fast WMA − Slow WMA, then apply a final WMA with a square‑root period. The implementation covers inputs, buffers, warm-up/recalculation, and visualization with a color-coded line and zero-line filling, helping interpret positive/negative momentum without treating zero crossings as signals.
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MQL5 Wizard Techniques you should know (Part 63): Using Patterns of DeMarker and Envelope Channels

MQL5 Wizard Techniques you should know (Part 63): Using Patterns of DeMarker and Envelope Channels

The DeMarker Oscillator and the Envelope indicator are momentum and support/resistance tools that can be paired when developing an Expert Advisor. We therefore examine on a pattern by pattern basis what could be of use and what potentially avoid. We are using, as always, a wizard assembled Expert Advisor together with the Patterns-Usage functions that are built into the Expert Signal Class.
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Hilbert-Schmidt Independence Criterion (HSIC)

Hilbert-Schmidt Independence Criterion (HSIC)

The article discusses the non-parametric HSIC (Hilbert-Schmidt Independence Criterion) statistical test designed to identify linear and non-linear dependencies in data. Implementations of two algorithms for calculating HSIC in the MQL5 language are proposed: the exact permutation test and the gamma approximation. The method efficiency is demonstrated on synthetic data modeling a non-linear relationship between features and the target variable.
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Larry Williams Market Secrets (Part 7): An Empirical Study of the Trade Day of the Week Concept

Larry Williams Market Secrets (Part 7): An Empirical Study of the Trade Day of the Week Concept

An empirical study of Larry Williams’ Trade Day of the Week concept, showing how time-based market bias can be measured, tested, and applied using MQL5. This article presents a practical framework for analyzing win rates and performance across trading days to improve short-term trading systems.
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Digital Signal Processing for Traders: Building Ehlers' Filter Library in MQL5

Digital Signal Processing for Traders: Building Ehlers' Filter Library in MQL5

We implement Ehlers-style DSP filters in a single reusable MQL5 library and use it to build two indicators. The Roofing Filter applies a 2‑pole high‑pass followed by a Super Smoother to isolate the tradeable 10–48‑bar band. The Even Better Sinewave normalizes the wave to about ±1, oscillating in cycle regimes and railing in trends, so you can read cycles and detect regime shifts in charts and EAs.
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Population optimization algorithms: Resistance to getting stuck in local extrema (Part II)

Population optimization algorithms: Resistance to getting stuck in local extrema (Part II)

We continue our experiment that aims to examine the behavior of population optimization algorithms in the context of their ability to efficiently escape local minima when population diversity is low and reach global maxima. Research results are provided.
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Overcoming The Limitation of Machine Learning (Part 1): Lack of Interoperable Metrics

Overcoming The Limitation of Machine Learning (Part 1): Lack of Interoperable Metrics

There is a powerful and pervasive force quietly corrupting the collective efforts of our community to build reliable trading strategies that employ AI in any shape or form. This article establishes that part of the problems we face, are rooted in blind adherence to "best practices". By furnishing the reader with simple real-world market-based evidence, we will reason to the reader why we must refrain from such conduct, and rather adopt domain-bound best practices if our community should stand any chance of recovering the latent potential of AI.
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Engineering Trading Discipline into Code (Part 7): Automating Equity Protection Through Governance Logic

Engineering Trading Discipline into Code (Part 7): Automating Equity Protection Through Governance Logic

Automated trading systems often focus heavily on signal generation while neglecting the mechanisms required to protect capital during periods of stress. This article presents an Equity Governance Framework in MQL5 that monitors drawdown conditions, evaluates equity pressure, and dynamically controls trading activity through a state-driven risk management model. By combining drawdown analysis, cooldown logic, trade authorization, and execution restrictions, the framework demonstrates how trading discipline can be engineered directly into code using a modular and extensible architecture.
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From Novice to Expert: Systematic Profit Conservation Using Candle Range Theory

From Novice to Expert: Systematic Profit Conservation Using Candle Range Theory

A hybrid exit engine for MQL5 replaces static TPs with CRT-derived structural levels. The CRT_ProfitConserve class secures a partial at the first level and then trails the remaining position by structural anchors rather than fixed pips. The article walks through the class API, essential methods, and example usage in EAs, providing a clear path to embed CRT-based exits into existing strategies.
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Developing a Replay System — Market simulation (Part 16): New class system

Developing a Replay System — Market simulation (Part 16): New class system

We need to organize our work better. The code is growing, and if this is not done now, then it will become impossible. Let's divide and conquer. MQL5 allows the use of classes which will assist in implementing this task, but for this we need to have some knowledge about classes. Probably the thing that confuses beginners the most is inheritance. In this article, we will look at how to use these mechanisms in a practical and simple way.
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MQL5 Wizard Techniques you should know (Part 55): SAC with Prioritized Experience Replay

MQL5 Wizard Techniques you should know (Part 55): SAC with Prioritized Experience Replay

Replay buffers in Reinforcement Learning are particularly important with off-policy algorithms like DQN or SAC. This then puts the spotlight on the sampling process of this memory-buffer. While default options with SAC, for instance, use random selection from this buffer, Prioritized Experience Replay buffers fine tune this by sampling from the buffer based on a TD-score. We review the importance of Reinforcement Learning, and, as always, examine just this hypothesis (not the cross-validation) in a wizard assembled Expert Advisor.
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Neural Networks in Trading: Piecewise Linear Representation of Time Series

Neural Networks in Trading: Piecewise Linear Representation of Time Series

This article is somewhat different from my earlier publications. In this article, we will talk about an alternative representation of time series. Piecewise linear representation of time series is a method of approximating a time series using linear functions over small intervals.
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Beyond the Clock (Part 1): Building Activity and Imbalance Bars in Python and MQL5

Beyond the Clock (Part 1): Building Activity and Imbalance Bars in Python and MQL5

The article replaces clock-based sampling with López de Prado's alternative bar types and provides two aligned implementations: a unified Python module for batch tick histories and an object‑oriented MQL5 library for live EAs. It covers Parquet/Dask infrastructure, data cleaning, and a single API. Practical issues are solved explicitly: zero‑tick time‑bar filtering, imbalance threshold initialization, EWM state persistence, and parity between Python and MQL5 outputs.
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Adaptive Social Behavior Optimization (ASBO): Schwefel, Box-Muller Method

Adaptive Social Behavior Optimization (ASBO): Schwefel, Box-Muller Method

This article provides a fascinating insight into the world of social behavior in living organisms and its influence on the creation of a new mathematical model - ASBO (Adaptive Social Behavior Optimization). We will examine how the principles of leadership, neighborhood, and cooperation observed in living societies inspire the development of innovative optimization algorithms.
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Designing a Partial Close Engine in MQL5 with Configurable Profit Ladders

Designing a Partial Close Engine in MQL5 with Configurable Profit Ladders

This MQL5 engine applies configurable profit ladders in R‑multiples to manage partial closes reliably. It prevents stranded remainders by rounding to lot step, computes close percentages from the original entry volume, and moves the stop to breakeven when configured. A supported filling mode is chosen automatically, and the download includes seven include files, a demo EA, and a verification script.
All about Automated Trading Championship: Registration
All about Automated Trading Championship: Registration

All about Automated Trading Championship: Registration

This article comprises useful materials that will help you learn more about the procedure of registration for participation in the Automated Trading Championship.
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Resampling techniques for prediction and classification assessment in MQL5

Resampling techniques for prediction and classification assessment in MQL5

In this article, we will explore and implement, methods for assessing model quality that utilize a single dataset as both training and validation sets.
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Measuring broker execution quality in MQL5: Why your live account doesn't match the backtest

Measuring broker execution quality in MQL5: Why your live account doesn't match the backtest

Live performance often drifts from backtests because of execution friction. We introduce an MQL5 diagnostic EA that records entry and exit slippage, asymmetry, observed spread, requotes, and per-leg latency, using a precise probe mode and an approximate passive mode, and writes every sample to CSV. Use the results to distinguish strategy issues from execution effects across your terminal, network, broker, and liquidity.
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Forecasting exchange rates using classic machine learning methods: Logit and Probit models

Forecasting exchange rates using classic machine learning methods: Logit and Probit models

In the article, an attempt is made to build a trading EA for predicting exchange rate quotes. The algorithm is based on classical classification models - logistic and probit regression. The likelihood ratio criterion is used as a filter for trading signals.
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Overcoming The Limitation of Machine Learning (Part 9): Correlation-Based Feature Learning in Self-Supervised Finance

Overcoming The Limitation of Machine Learning (Part 9): Correlation-Based Feature Learning in Self-Supervised Finance

Self-supervised learning is a powerful paradigm of statistical learning that searches for supervisory signals generated from the observations themselves. This approach reframes challenging unsupervised learning problems into more familiar supervised ones. This technology has overlooked applications for our objective as a community of algorithmic traders. Our discussion, therefore, aims to give the reader an approachable bridge into the open research area of self-supervised learning and offers practical applications that provide robust and reliable statistical models of financial markets without overfitting to small datasets.
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MQL5 Wizard Techniques you should know (Part 12): Newton Polynomial

MQL5 Wizard Techniques you should know (Part 12): Newton Polynomial

Newton’s polynomial, which creates quadratic equations from a set of a few points, is an archaic but interesting approach at looking at a time series. In this article we try to explore what aspects could be of use to traders from this approach as well as address its limitations.
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From Basic to Intermediate: Recursion

From Basic to Intermediate: Recursion

In this article we will look at a very interesting and quite challenging programming concept, although it should be treated with great caution, as its misuse or misunderstanding can turn relatively simple programs into something unnecessarily complex. But when used correctly and adapted perfectly to equally suitable situations, recursion becomes an excellent ally in solving problems that would otherwise be much more laborious and time-consuming. The materials presented here are intended for educational purposes only. Under no circumstances should the application be viewed for any purpose other than to learn and master the concepts presented.
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Overcoming The Limitation of Machine Learning (Part 3): A Fresh Perspective on Irreducible Error

Overcoming The Limitation of Machine Learning (Part 3): A Fresh Perspective on Irreducible Error

This article takes a fresh perspective on a hidden, geometric source of error that quietly shapes every prediction your models make. By rethinking how we measure and apply machine learning forecasts in trading, we reveal how this overlooked perspective can unlock sharper decisions, stronger returns, and a more intelligent way to work with models we thought we already understood.
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Analyzing the Hourly Movement of Trading Symbols and Their Spreads in MetaTrader 5

Analyzing the Hourly Movement of Trading Symbols and Their Spreads in MetaTrader 5

The ProSpread seasonality index indicator with a Moving Average is a technical analysis tool that identifies seasonal patterns in price movements, analyzes price behavior during specific trading hours and is able to work with either a single instrument or a spread between two assets. It also visualizes the statistical probability of directional movements.
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Reinforcement Learning Meets MetaTrader 5: A Complete Pipeline for Training, Validating and Honestly Evaluating a Gold Trading Bot

Reinforcement Learning Meets MetaTrader 5: A Complete Pipeline for Training, Validating and Honestly Evaluating a Gold Trading Bot

This article presents a complete RL trading pipeline for XAUUSD: a supervised signal baseline with triple-barrier labels, PPO training, purged walk-forward validation with embargo, multi-seed checks, and contract-guarded deployment with normalization. It includes runnable code for data validation, features, environment, training, and broker‑based reconciliation. The live demo over 763 closed trades showed no statistically significant edge, and the methods highlight where information and costs, not architecture, set performance limits.
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Introduction to MQL5 (Part 32): Mastering API and WebRequest Function in MQL5 (VI)

Introduction to MQL5 (Part 32): Mastering API and WebRequest Function in MQL5 (VI)

This article will show you how to visualize candle data obtained via the WebRequest function and API in candle format. We'll use MQL5 to read the candle data from a CSV file and display it as custom candles on the chart, since indicators cannot directly use the WebRequest function.
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Defining your Edge (Part 1): Using a Discrete Fourier Transform and a Spiking Neural Network in a Trading Robot

Defining your Edge (Part 1): Using a Discrete Fourier Transform and a Spiking Neural Network in a Trading Robot

In this article we make the case for pairing the Discrete Fourier Transform with a Spiking Neural Network in a Trading Robot. The Fourier Transform helps represent data as oscillations instead of its raw values. To govern how we interpret these cycles, we engage a Spiking Neural Network that unlike regular networks, uses time dependent electrical charges to accumulate potential and only "spike" when a target threshold is met. Combining these two engines allows us better control on the timing of discrete market movements, that in theory should give us entry signals with rigorous mathematical confirmation.
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Integrating MQL5 with data processing packages (Part 3): Enhanced Data Visualization

Integrating MQL5 with data processing packages (Part 3): Enhanced Data Visualization

In this article, we will perform Enhanced Data Visualization by going beyond basic charts by incorporating features like interactivity, layered data, and dynamic elements, enabling traders to explore trends, patterns, and correlations more effectively.