Articles with MQL4 programming examples

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Access a huge collection of articles with code examples showing how to create indicators and trading robots for the MetaTrader platform in the MQL5 language. Source codes are attached to the articles, so you can open them in MetaEditor and run them to see how the applications work.

These articles will be useful both for those who have just started exploring automated trading and for professional traders with programming experience. They feature not only examples, but also contain new ideas.

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Why Is It Important to Update MetaTrader 4 to the Latest Build by August 1?
Why Is It Important to Update MetaTrader 4 to the Latest Build by August 1?

Why Is It Important to Update MetaTrader 4 to the Latest Build by August 1?

From August 1, 2014, MetaTrader 4 desktop terminals older than build 600 will no longer be supported. However, many traders still work with outdated versions and are unaware of the updated platform's features. We have put a lot of effort into development and would like to move on with traders and abandon the older builds. In this article, we will describe the advantages of the new MetaTrader 4.
Working with Doubles in MQL4
Working with Doubles in MQL4

Working with Doubles in MQL4

In this note we will consider a typical programming errors, that occurs while working with double numbers in MQL4 programs.
Secrets of MetaTrader 4 Client Terminal: Alerting System
Secrets of MetaTrader 4 Client Terminal: Alerting System

Secrets of MetaTrader 4 Client Terminal: Alerting System

How to be aware of what happens in the terminal and on your account without permanent looking at the monitor. System events; custom events; wave and executable files; electronic messages; setting up SMTP server access; publications; setting up FTP server access.
Expert Advisor for Trading in the Channel
Expert Advisor for Trading in the Channel

Expert Advisor for Trading in the Channel

The Expert Advisor plots the channel lines. The upper and lower channel lines act as support and resistance levels. The Expert Advisor marks datum points, provides sound notification every time the price reaches or crosses the channel lines and draws the relevant marks. Upon fractal formation, the corresponding arrows appear on the last bars. Line breakouts may suggest the possibility of a growing trend. The Expert Advisor is extensively commented throughout.
Enhancing the StrategyTester to Optimize Indicators Solely on the Example of Flat and Trend Markets
Enhancing the StrategyTester to Optimize Indicators Solely on the Example of Flat and Trend Markets

Enhancing the StrategyTester to Optimize Indicators Solely on the Example of Flat and Trend Markets

It is essential to detect whether a market is flat or not for many strategies. Using the well known ADX we demonstrate how we can use the Strategy Tester not only to optimize this indicator for our specific purpose, but as well we can decide whether this indicator will meet our needs and get to know the average range of the flat and trend markets which might be quite important to determine stops and targets of the markets.
Integrating MetaTrader 4  Client Terminal with MS SQL Server
Integrating MetaTrader 4  Client Terminal with MS SQL Server

Integrating MetaTrader 4 Client Terminal with MS SQL Server

The article gives an example of integrating MetaTrader 4 Client Terminal with MS SQL Server using a dll. Attached are both source codes in С++ and in MQL4, and a ready-made and compiled Visual C++ 6.0 SP5 project.
File Operations via WinAPI
File Operations via WinAPI

File Operations via WinAPI

Environment MQL4 is based on the conception of safe "sandbox": reading and saving files using the language are allowed in some predefined folders only. This protects the user of MetaTrader 4 from the potential danger of damaging important data on the HDD. However, it is sometimes necessary to leave that safe area. This article is devoted to the problem of how to do it easily and correctly.
Error 146 ("Trade context busy") and How to Deal with It
Error 146 ("Trade context busy") and How to Deal with It

Error 146 ("Trade context busy") and How to Deal with It

The article deals with conflict-free trading of several experts on one МТ 4 Client Terminal. It will be useful for those who have basic command of working with the terminal and programming in MQL 4.
FANN2MQL Neural Network Tutorial
FANN2MQL Neural Network Tutorial

FANN2MQL Neural Network Tutorial

This article has been made to show you how to use neural networks, via FANN2MQL, using an easy example: teaching a simple pattern to the neuralnetwork, and testing it to see if it can recognize patterns it has never seen.
Secrets of the MetaTrader 4 Client Terminal: Indicators
Secrets of the MetaTrader 4 Client Terminal: Indicators

Secrets of the MetaTrader 4 Client Terminal: Indicators

Are you going to write your own indicator? Perhaps you will find that what you need among indicators already embedded in the client terminal. So why to reinvent the wheel? A summary table of integrated indicators' characteristics; special features and methods of attaching indicators to a chart; building of levels; displaying of indicators on different timeframes.
On Methods of Technical Analysis and Market Forecasting
On Methods of Technical Analysis and Market Forecasting

On Methods of Technical Analysis and Market Forecasting

The article demonstrates the capabilities and potential of a well-known mathematical method coupled with visual thinking and an "out of the box" market outlook. On the one hand, it serves to attract the attention of a wide audience as it can get the creative minds to reconsider the trading paradigm as such. And on the other, it can give rise to alternative developments and program code implementations regarding a wide range of tools for analysis and forecasting.
An Insight Into Accumulation/Distribution And Where It Can Get You
An Insight Into Accumulation/Distribution And Where It Can Get You

An Insight Into Accumulation/Distribution And Where It Can Get You

The Accumulation/Distribution (A/D) Indicator has one interesting feature - a breakout of the trend line plotted in this indicator chart suggests, with a certain degree of probability, a forthcoming breakout of the trend line in the price chart. This article will be useful and interesting for those who are new to programming in MQL4. Having this in view, I have tried to present the information in an easy to grasp manner and use the simplest code structures.
Easy Stock Market Trading with MetaTrader
Easy Stock Market Trading with MetaTrader

Easy Stock Market Trading with MetaTrader

This article raises the issues of automated trading on the stock market. Examples of MetaTrader 4 and QUIK integration are provided for your information. In addition to that, you can familiarize yourself with MetaTrader advantages aimed at solving this issue, and see how a trading robot can perform operations on MICEX.
A Method of Drawing the Support/Resistance Levels
A Method of Drawing the Support/Resistance Levels

A Method of Drawing the Support/Resistance Levels

This article describes the process of creating a simple script for detecting the support/resistance levels. It is written for beginners, so you can find the detailed explanation of every stage of the process. However, though the script is very simple, the article will be also useful for advanced traders and the users of the MetaTrader 4 platform. It contains the examples of the data export into the tabular format, the import of the table to Microsoft Excel and plotting the charts for the further detailed analysis.
An Expert Advisor Made to Order. Manual for a Trader
An Expert Advisor Made to Order. Manual for a Trader

An Expert Advisor Made to Order. Manual for a Trader

Not all traders are programmers. And not all of the programmers are really good ones. So, what should be done, if you need to automate your system by do not have time and desire to study MQL4?
Transferring an Indicator Code into an Expert Advisor Code. General Structural Schemes of an Expert Advisor and Indicator Functions
Transferring an Indicator Code into an Expert Advisor Code. General Structural Schemes of an Expert Advisor and Indicator Functions

Transferring an Indicator Code into an Expert Advisor Code. General Structural Schemes of an Expert Advisor and Indicator Functions

This article dwells on the ways of transferring an indicator code into an Expert Advisor Code and on writing Expert Advisors with no calling to custom indicators, and with the whole program code for the calculation of necessary indicator values inside the Expert Advisor. This article gives a general scheme of Expert Advisor changing and the idea of building an indicator function based on a custom indicator. The article is intended for readers, already having experience of programming in MQL4 language.
Alert and Comment for External Indicators. Multi-Currency Analysis Through External Scanning
Alert and Comment for External Indicators. Multi-Currency Analysis Through External Scanning

Alert and Comment for External Indicators. Multi-Currency Analysis Through External Scanning

Alert for multi-currency and multiple time frame analysis of external indicators. The article deals with a method of getting event information in respect of events in external indicators, without having to attach indicators to a chart or open charts themselves. We will call it external scanning.
Strings: Table of ASCII Symbols and Its Use
Strings: Table of ASCII Symbols and Its Use

Strings: Table of ASCII Symbols and Its Use

In this article we will analyze the table of ASCII symbols and the ways it can be used. We will also deal with some new functions, the principle of operation of which is based on the peculiarities of the ASCII table, and then we will create a new library, which will include these functions. They are quite popular in other programming languages, but they are not included into the list of built-in functions. Besides, we will examine in details the basics of working with strings. So, I think you will certainly learn something new about this useful type of data.
Synchronization of Expert Advisors, Scripts and Indicators
Synchronization of Expert Advisors, Scripts and Indicators

Synchronization of Expert Advisors, Scripts and Indicators

The article considers the necessity and general principles of developing a bundled program that would contain both an Expert Advisor, a script and an indicator.
Forex Trading ABC
Forex Trading ABC

Forex Trading ABC

Working on financial markets represents, first of all, trade operations. We all, starting from the very childhood, have an intuitive idea of what is to buy and to sell. But Forex trading is still something special. This article deals with the ideas necessary to explain some terms. We will also consider the MQL 4 functions that correspond with those terms.
Graphic Expert Advisor: AutoGraf
Graphic Expert Advisor: AutoGraf

Graphic Expert Advisor: AutoGraf

The article shows the workability of graphics in creation of a convenient interface to manage trading.
Indicator Alternative Ichimoku – Setup, Examples of Usage
Indicator Alternative Ichimoku – Setup, Examples of Usage

Indicator Alternative Ichimoku – Setup, Examples of Usage

How to set up Alternative Ichimoku correctly? Read the description of parameters setting up. The article will help you understand the methods of setting up parameters not only of the indicator Ichimoku. Certainly you will also better understand how to set up the standard Ichimoku Kinko Hyo.
Interaction between MеtaTrader 4 and MATLAB Engine (Virtual MATLAB Machine)
Interaction between MеtaTrader 4 and MATLAB Engine (Virtual MATLAB Machine)

Interaction between MеtaTrader 4 and MATLAB Engine (Virtual MATLAB Machine)

The article contains considerations regarding creation of a DLL library - wrapper that will enable the interaction of MetaTrader 4 and the MATLAB mathematical desktop package. It describes "pitfalls" and ways to overcome them. The article is intended for prepared C/C++ programmers that use the Borland C++ Builder 6 compiler.
Interaction between MetaTrader 4 and Matlab via CSV Files
Interaction between MetaTrader 4 and Matlab via CSV Files

Interaction between MetaTrader 4 and Matlab via CSV Files

Step-by-step instructions of how to organize data arrays exchange between MetaTrader 4 and Matlab via CSV files.
A Pause between Trades
A Pause between Trades

A Pause between Trades

The article deals with the problem of how to arrange pauses between trade operations when a number of experts work on one МТ 4 Client Terminal. It is intended for users who have basic skills in both working with the terminal and programming in MQL 4.
Program Folder of MetaTrader 4 Client Terminal
Program Folder of MetaTrader 4 Client Terminal

Program Folder of MetaTrader 4 Client Terminal

The article describes the contents of the program folder of MetaTrader 4 Client Terminal. The article will be useful for those who have already started to grasp into the details of the client terminal operation.
Reading RSS News Feeds by Means of MQL4
Reading RSS News Feeds by Means of MQL4

Reading RSS News Feeds by Means of MQL4

This article deals with an example of reading RSS markup by means of MQL4 using the functions for HTML tags analysis. We will try to make a work piece which can then be turned into a news indicator or just an RSS reader on MQL4 language.
Three Aspects of Manual Trading Automation. Part 1: Trading
Three Aspects of Manual Trading Automation. Part 1: Trading

Three Aspects of Manual Trading Automation. Part 1: Trading

This article is the first in a series of articles on manual trading automation in the МetaТrader 4 trading platform. Each of the articles will be devoted to one of the following aspects: automation of manual trading, current state of trade display automation and automation of reports on trade results. In this article, I will present an interesting approach to creating EA's controlled manually by a trader.
Breakpoints in Tester: It's Possible!
Breakpoints in Tester: It's Possible!

Breakpoints in Tester: It's Possible!

The article deals with breakpoint emulation when passed through Tester, debug information being displayed.
Can the Forex Market Be Forecasted? How to Create One's Own Trading Strategy?
Can the Forex Market Be Forecasted? How to Create One's Own Trading Strategy?

Can the Forex Market Be Forecasted? How to Create One's Own Trading Strategy?

Everyone starting to work in Forex tries to answer these questions. But not everyone finds the answer, even after many years of hard work and search. I personally have answered this question, as well as many other questions of this article. As a result of these answers a way of creating an efficient trading strategy was determined.
Pivot Points Helping to Define Market Trends
Pivot Points Helping to Define Market Trends

Pivot Points Helping to Define Market Trends

Pivot point is a line in the price chart that shows the further trend of a currency pair. If the price is above this line, it tends to grow. If the price is below this line, accordingly, it tends to fall.
Research of Statistical Recurrences of Candle Directions
Research of Statistical Recurrences of Candle Directions

Research of Statistical Recurrences of Candle Directions

Is it possible to predict the behavior of the market for a short upcoming interval of time, based on the recurring tendencies of candle directions, at specific times throughout the day? That is, If such an occurrence is found in the first place. This question has probably arisen in the mind of every trader. The purpose of this article is to attempt to predict the behavior of the market, based on the statistical recurrences of candle directions during specific intervals of time.
Changing the External Parameters of MQL4 Programs without Restarting
Changing the External Parameters of MQL4 Programs without Restarting

Changing the External Parameters of MQL4 Programs without Restarting

The article describes a method of changing the external parameters of MQL4 programs on-the-fly, without restarting.
Free-of-Holes Charts
Free-of-Holes Charts

Free-of-Holes Charts

The article deals with realization of charts without skipped bars.
HTML Walkthrough Using MQL4
HTML Walkthrough Using MQL4

HTML Walkthrough Using MQL4

HTML is nowadays one of the wide-spread types of documents. MetaTrader 4 Client Terminal allows you to save statements, test and optimization reports as .htm files. It is sometimes necessary to get information from such files in an MQL4 program. The article describes one of variations of how to get the tag structure and contents from HTML.
Equivolume Charting Revisited
Equivolume Charting Revisited

Equivolume Charting Revisited

The article dwells on the method of constructing charts, at which each bar consists of the equal number of ticks.
Visual Optimization of Indicator and Signal Profitability
Visual Optimization of Indicator and Signal Profitability

Visual Optimization of Indicator and Signal Profitability

This article is a continuation and development of my previous article "Visual Testing of Profitability of Indicators and Alerts". Having added some interactivity to the parameter changing process and having reworked the study objectives, I have managed to get a new tool that does not only show the prospective trade results based on the signals used but also allows you to immediately get a layout of deals, balance chart and the end result of trading by moving virtual sliders that act as controls for signal parameter values in the main chart.
Recipes for Neuronets
Recipes for Neuronets

Recipes for Neuronets

The article is intended for beginners in baking "multi-layered" cakes.
Multiple Null Bar Re-Count in Some Indicators
Multiple Null Bar Re-Count in Some Indicators

Multiple Null Bar Re-Count in Some Indicators

The article is concerned with the problem of re-counting of the indicator value in the MetaTrader 4 Client Terminal when the null bar changes. It outlines general idea of how to add to the indicator code some extra program items that allow to restore program code saved before multiple re-counting.
Effective Averaging Algorithms with Minimal Lag: Use in Indicators
Effective Averaging Algorithms with Minimal Lag: Use in Indicators

Effective Averaging Algorithms with Minimal Lag: Use in Indicators

The article describes custom averaging functions of higher quality developed by the author: JJMASeries(), JurXSeries(), JLiteSeries(), ParMASeries(), LRMASeries(), T3Series(). The article also deals with application of the above functions in indicators. The author introduces a rich indicators library based on the use of these functions.