Indholdsfortegnelse for Coding for Beginners i Coding for Beginners

01000011 01101111 01100100 01100101 Essentially all forms of coding are made up of ones and zeros, on or off states. This works for a modern computer and even the oldest known computational device. ~87 BC It’s difficult to pinpoint an exact start of when humans began to ‘program’ a device. However, it’s widely accepted that the Antikythera Mechanism is possibly the first ‘coded’ artefact. It’s dated to about 87 BC and is an ancient Greek analogue computer and orrery used to predict astronomical positions. ~850 AD The Banū Mūsā brothers, three Persian scholars who worked in the House of Wisdom in Baghdad, published the Book of Ingenious Devices in around 850 AD. Among the inventions listed was a mechanical musical instrument, a hydro-powered organ that played interchangeable cylinders automatically. 1800…

C++ is an amazing programming language. Most of what you see in front of you when you power up your computer, regardless of whether you’re using Windows, macOS or Linux, is created using C++. Being able to code in C++ will open a whole new world for you, in terms of desirable professional skills and the ability to code amazing apps and games. C++ is an efficient and powerful language that’s used to develop operating systems, applications, games and much more. It’s used in science, engineering, banking, education, the space industry, and much more.…

C++ SETUPS As most, if not all, operating systems have C++ at their code, it stands to reason that you can learn to program in C++ no matter what OS you’re currently using. □ COMPUTER Unless you fancy writing out your C++ code by hand on a sheet of paper (which is something many older coders used to do), then a computer is an absolute must have component. PC users can have any recent Linux distro or Windows OS, Mac users the latest macOS. □ AN IDE An IDE is used to enter and execute your C++ code. Many IDEs come with extensions and plugins that help make it work better, or add an extra level of functionality. Often, an IDE will provide enhancements depending on the core OS being…

XCODE Apple’s Xcode is primarily designed for users to develop apps for macOS, iOS, tvOS and watchOS applications in Swift or Objective-C, but we can use it for C++ too. STEP 1 Start by opening the App Store on your Mac, Apple Menu > App Store. In the Search box enter Xcode, and press Return. There will be many suggestions filling the App Store window, but it’s first option, Xcode, that you need to click on. STEP 2 Take a moment to browse through the app’s information, including the compatibility to ensure you have the correct version of macOS. Xcode requires macOS 10.12.6 or later to install and work. STEP 3 When you’re ready, click on the Get or cloud icon button which will install the Xcode app. Enter your…

This section contains the building block of C++, from learning how to compile and execute your first C++ code, through to developing user interaction. There’s a lot to learn with C++, but these tutorials, tips and tricks will lead you in the right direction. C++ is different to the other programming languages in this book, and it’s continually evolving as the applications that require it are forever improving. If you know C++, then you’re well on your way to becoming a much sought-after coder and a vital member of the coding community.…

THE IMPORTANCE OF COMMENTING Comments inside code are basically human readable descriptions that detail what the code is doing at that particular point. They don’t sound especially important but code without comments is one of the many frustrating areas of programming, regardless of whether you’re a professional or just starting out. In short, all code should be commented in such a manner as to effectively describe the purpose of a line, section, or individual elements. You should get in to the habit of commenting as much as possible, by imagining that someone who doesn’t know anything about programming can pick up your code and understand what it’s going to do simply by reading your comments. In a professional environment, comments are vital to the success of the code and ultimately,…

STRING THEORY There are different ways in which you can create a string of characters, which historically are all carried over from the original C language, and are still supported by C++. STEP 1 To create a string you use the char function. Open a new C++ file and begin with the usual header: STEP 2 It’s easy to confuse a string with an array. Here’s an array, which can be terminated with a null character: STEP 3 Build and run the code, and ‘Welcome’ appears on the screen. While this is perfectly fine, it’s not a string. A string is a class, which defines objects that can be represented as a stream of characters and doesn’t need to be terminated like an array. The code can therefore be represented…

Python is one of the most respected and used programming languages in the world. It’s designed to help beginners get into code, but also has some amazingly powerful features that are utilised by data scientists and engineers around the world. You don’t need to look too far to Python at work. It’s used throughout the Internet, and helps drive some of the biggest projects and companies in a multitude of industries. In this section, we will look at what you will need to get started with Python. First steps into a new learning experience are always the hardest, but we’re here to help.…

Python creator Guido Van Rossum named Python after reading scripts from Monty Python’s Flying Circus. Alexa, Amazon’s Virtual Personal Assistant, uses Python to help with speech recognition. As of the end of 2018, Python was the most discussed language on the Internet. PYTHON AND LINUX SKILLS ARE THE THIRD MOST POPULAR I.T. SKILLS IN THE UK. Data analysis and Machine Learning are the two most used Python examples. Disney Pixar uses Python in its Renderman software to operate between other graphics packages. OVER 75% OF RECOMMENDED CONTENT FROM NETFLIX IS GENERATED FROM MACHINE LEARNING – CODED BY PYTHON. 90% OF ALL FACEBOOK POSTS ARE FILTERED THROUGH PYTHONCODED MACHINE LEARNING. IT’S ESTIMATED THAT OVER 75% OF NASA’S WORKFLOW AUTOMATION SYSTEMS ON BOARD THE I.S.S. USE PYTHON. 16,000 There are over 16,000…

INSTALLING PYTHON 3.X Microsoft Windows doesn’t come with Python pre-installed as standard, so you’re going to have to install it yourself manually. Thankfully, it’s an easy process to follow. STEP 1 Start by opening your web browser to www.python.org/downloads/. Look for the button detailing the Download link for Python 3.x. Python is regularly updated, changing the last digit for each bug fix and update. Therefore, don’t worry if you see Python 3.7.0, or more, as long as it’s Python 3, the code in this book will work fine. STEP 2 Click the download button for version 3.x, and save the file to your Downloads folder. When the file is downloaded, double-click the executable and the Python installation wizard will launch. From here you’ll have two choices: Install Now and Customise…

It’s a long way from creating your fist Python code to controlling a robot on Mars, but it’s not impossible. Every advanced and professional Python coder started with the base fundamentals, tips and fixes mentioned in this section. With these foundation Python concepts, you will be able to advance your skills and branch out into whatever Python project you have in mind. From printing Hello World on the screen, looking into conditions and loops, asking a user for input and reacting to it, to using variables to control your code, this is where your Python skills are forged.…

EDITING CODE You will eventually reach a point where you have to move on from inputting single lines of code into the Shell. Instead, the IDLE Editor will allow you to save and execute your Python code. STEP 1 First, open the Python IDLE Shell. When it’s up, click on File > New File, this will open a new window with Untitled as its name. This is the Python IDLE Editor, and within it, you can enter the code you need to create your future programs. STEP 2 The IDLE Editor is, for all intents and purposes, a simple text editor with Python features, colour coding and so on. You enter code as you would within the Shell, so taking an example from the previous tutorial, enter: STEP 3 As…

IT’S ALL MATHS, MAN You can get some really impressive results from the mathematical powers of Python, as maths is the driving force behind the code with most, if not all, programming languages. STEP 1 Open up the GUI version of Python 3, as mentioned you can use either the Shell or the Editor. For the time being, we’re going to use the Shell. If you’ve opted to use a third-party text editor, note that you need to get to the IDLE Shell for this part of the tutorial. STEP 2 In the Shell enter the following: As you can see, Python can handle some quite large numbers. STEP 3 You can use all the customary Mathematical operations: divide, multiply, brackets and so on. Practise with a few, for example:…

MASTERING MODULES Think of modules as an extension that’s imported into your Python code to enhance and extend its capabilities. There are countless modules available, and as we’ve seen, you can even make your own. STEP 1 Although good, the built-in functions within Python are limited. The use of modules, however, allows us to make more sophisticated programs. As you are aware, modules are Python scripts that are imported, such as import math. STEP 2 Some modules, especially on the Raspberry Pi, are included by default; the Math module is a prime example. Sadly, other modules aren’t always available. A good example on non-Pi platforms is the Pygame module, which contains many functions to help create games. Try: import pygame. STEP 3 The result is an error in the IDLE…

LINUX MINT – LINUXMINT.COM By far the most popular Linux distro (distribution) is Linux Mint. Mint began life back in 2006, as an alternative to the then, most popular distro, Ubuntu. Although based on Ubuntu’s Long Term Support build, Linux Mint took a different direction to offer the user a better overall experience. Linux Mint has three main desktop versions available with each new version of the core OS it releases. This may sound confusing at first, but it’s quite simple. Currently, Linux Mint uses the Cinnamon Desktop Environment as its flagship model, although MATE and Xfce models are also available. Cinnamon is a graphically rich desktop environment, while MATE uses less fancy graphics but is more stable on a wider variety of desktop systems and finally Xfce is an…

UEFI BIOS The Unified Extensible Firmware Interface (UEFI) is used to identify hardware and protect a PC during its boot-up process. It replaces the traditional BIOS, but can cause issues when installing Linux. STEP 1 Insert your DVD or USB flash drive into your PC and, if you haven’t already, shutdown Windows. In this instance, we’re using the USB boot media but the process is virtually identical. Start the PC and when prompted press the appropriate keys to enter the BIOS or SETUP; these could be, for example, F2, Del or even F12. STEP 2 There are different versions of a UEFI BIOS, so covering them all would be impossible. What you’re looking for is a section that details the Boot Sequence or Boot Mode. Here you’ll have the option…

TAKING COMMAND The command line is at the core of Linux and when you program with it, this is called scripting. These are self-contained programs designed to be run in the Terminal. STEP 1 The Terminal is where you begin your journey with Linux, through the command line and thus any scripting from. In Linux Mint, it can be accessed by clicking on the Menu followed by the Terminal icon in the panel, or entering ‘Terminal’ into the search bar. STEP 2 The Terminal will give you access to the Linux Mint Shell, called BASH; this gives you access to the underlying operating system, which is why scripting is such a powerful language to learn and use. Everything in Mint, and Linux as a whole, including the desktop and GUI,…

IF, THEN, ELSE With most programming structures there will come a time where you need to loop through the commands you’ve entered to create better functionality, and ultimately a better program. STEP 1 Let’s look at the If, Then and Else statements now, which when executed correctly, compare a set of instructions and simply work out that IF something is present, THEN do something, ELSE do something different. Create a new script called greeting2.sh and enter the text in the screenshot below into it. STEP 2 Greeting2.sh is a copy of greeting.sh but with a slight difference. Here we’ve added a loop starting at the if statement. This means, IF the variable entered is equal to David the next line, THEN, is the reaction to what happens, in this case…

You will reach a point in your Python coding experience when you need to rely on some external resources to help you through a sticky patch in your project or give you a bit of inspiration. Python resources are available throughout the Internet, but not all of them are any good. If you spend any time looking up code for a particular project, then you’re likely to come across copious examples, yet not all of them seem to work. That’s one of the main issues with resources for Python. With the language being twenty-nine years old, and many different versions under the bridge, there’s a significant amount of content out there that’s simply out of date – or just wrong for the version you’re using. Newer versions, even by one…

ADVENTURE.PY The Adventure game uses just the Time module to begin with, creating pauses between print functions. There’s a help system in place to expand upon, as well as the story itself. Adventure Time This, as you can see, is just the beginning of the adventure and takes up a fair few lines of code. When you expand it, and weave the story along, you’ll find that you can repeat certain instances such as a chance meeting with an enemy or the like. We’ve created each of the two encounters as a defined set of functions, along with a list of possible choices under the cmdlist list, and cmd variable, of which is also a defined function. Expanding on this is quite easy, just map out each encounter and choice…

VOID(C++, MISTAKES) Admittedly it’s not just C++ beginners that make the kinds of errors we outline on these pages, even hardened coders are prone to the odd mishap here and there. Here are some common issues to try and avoid. UNDECLARED IDENTIFIERS A common C++ mistake, and to be honest a common mistake with most programming languages, is when you try and output a variable that doesn’t exist. Displaying the value of x on-screen is fine but not if you haven’t told the compiler what the value of x is to begin with. SEMICOLONS Remember that each line of a C++ program must end with a semicolon. If it doesn’t then the compiler treats the line with the missing semicolon as the same line with the next semicolon on. This…

Everything you do online, every time you power on your smart TV, whenever you use your in-car GPS, use your phone, play a game on a tablet, console or PC, it’s all been coded by a group of people. All these ones and zeros are developed by those who have learned how to code, and with this book you too can learn how to get started on the road to becoming a programmer. We cover C++, Python, and Linux Scripting within these pages. There’s a huge section of project ideas, type-in listings, and in-depth looks at how code works. But first, let’s begin with a good foundation.…

SQL SQL stands for Structured Query Language. SQL is a standard language for accessing and manipulating databases. Although SQL is an ANSI (American National Standards Institute) standard, there are different versions of the SQL language. However, to be compliant, they all support at least the major commands such as Select, Update and Delete in a similar manner. JAVASCRIPT JavaScript (often shortened to JS) is a lightweight, interpreted, object-oriented language with first class functions. JavaScript runs on the client side of the web, that can be used to design or program how the web pages behave on the occurrence of an event. JavaScript is an easy to learn and also powerful scripting language, widely used for controlling web page behaviour. JAVA Java is the foundation for virtually every type of networked…

LINUX++ There are many different versions of Linux available, for this example we’re using one of the more popular distributions: Linux Mint. However, these steps will work in any Debian-based Linux. STEP 1 The first step with ensuring Linux is ready for your C++ code is check the system and software are up to date. Open a Terminal and enter: sudo apt-get update && sudo apt-get upgrade. Press Return and enter your password. These commands updates the entire system and any installed software. STEP 2 Most Linux distros come preinstalled with all the necessary components to start coding in C++. However, it’s always worth checking to see if everything is present, so still within the Terminal, enter: sudo apt-get install build-essential and press Return. If you have the right components,…

HELLO, WORLD! It’s traditional in programming for the first code to be entered to output the words ‘Hello, World!’ to the screen. Interestingly, this dates back to 1968 using a language called BCPL. STEP 1 We’re going to use Windows 10 and the excellent IDE Code::Blocks for the rest of the C++ code and tutorials in this book. Begin by launching Code::Blocks. When open, click on File > New > Empty File or press Ctrl+Shift+N on the keyboard. STEP 2 Now you can see a blank screen, with the tab labelled *Untitled1, and the number one in the top left of the main Code::Blocks window. Begin by clicking in the main window, so the cursor is next to the number one, and entering: #include <iostream> STEP 3 At the moment…

THE DECLARATION OF VARIABLES You can declare a C++ variable by using statements within the code. There are several distinct types of variables you can declare. Here’s how it works. STEP 1 Open up a new, blank C++ file and enter the usual code headers: STEP 2 Start simple by creating two variables, a and b, with one having a value of 10 and the other 5. You can use the data type int to declare these variables. Within the curly brackets, enter: STEP 3 You can build and run the code but it won’t do much, other than store the values 10 and 5 to the integers a and b. To output the contents of the variables, add: The cout << “\n”; part simply places a new line between…

C++ = MC2 The basic mathematical symbols apply in C++ as they do in most other programming languages. However, by using the C++ Math Library, you can also calculate square roots, powers, trig and more. STEP 1 C++’s mathematical operations follow the same patterns as those taught in school, in that multiplication and division take precedence over addition and subtraction. You can alter that though. For now, create a new file and enter: STEP 2 While simple, it does get the old maths muscle warmed up. Note that we used a float for the numbers variable. While you can happily use an integer, if you suddenly started to use decimals, you would need to change to a float or a double, depending on the accuracy needed. Run the code and…

PYTHON POWER Ever since the earliest home computers were available, enthusiasts, users and professionals have toiled away until the wee hours, slaving over an overheating heap of circuitry to create something akin to magic. These pioneers of programming carved their way into a new frontier, forging small routines that enabled the letter ‘A’ to scroll across the screen. It may not sound terribly exciting to a generation that’s used to ultra high-definition graphics and open world, multiplayer online gaming. However, forty-something years ago it was blindingly brilliant. Naturally these bedroom coders helped form the foundations for every piece of digital technology we use today. Some went on to become chief developers for top software companies, whereas others pushed the available hardware to its limits and founded the billion pound gaming…

WHAT WE’RE USING Thankfully, Python is a multi-platform programming language available for Windows, macOS, Linux, Raspberry Pi and more. If you have one of those systems, then you can easily start using Python. □ COMPUTER Obviously you’re going to need a computer in order to learn how to program in Python and to test your code. You can use Windows (from XP onward) on either a 32 or 64-bit processor, an Apple Mac or Linux installed PC. □ AN IDE An IDE (Integrated Developer Environment) is used to enter and execute Python code. It enables you to inspect your program code and the values within the code, as well as offering advanced features. There are many different IDEs available, so find the one that works for you and gives the…

PYTHON PENGUIN Linux is such a versatile operating system that it’s often difficult to nail down just one-way of doing something. Different distributions go about installing software in different ways, so for this particular tutorial we will stick to Linux Mint. STEP 1 First you need to ascertain which version of Python is currently installed in your Linux system. To begin with, drop into a Terminal session from your distro’s menu, or hit the Ctrl+Alt+T keys. STEP 2 Next, enter: python --version into the Terminal screen. You should have the output relating to version 2.x of Python in the display. Most Linux distro come with both Python 2 and 3 by default, as there’s plenty of code out there still available for Python 2. Now enter: python3 --version. STEP 3…

STARTING PYTHON As when learning anything new, you need to start slow. You can pick up the pace as your experience grows, but for now, let’s just get something appearing on the screen. Don’t worry, you’ll soon be coding like a pro! STEP 1 Click on the Windows Start button, and start typing ‘idle’. The result will be the currently installed version of the Python IDLE on your system. You can Pin it to the Start for convenience, otherwise simply click the icon to launch the Python Shell. STEP 2 The Shell is where you can enter code and see the responses and output of code you’ve programmed into Python. This is a kind of sandbox, if you will, where you’re able to try out some simple code and processes.…

COMMAND THE CODE Using the code we created in the previous tutorial, the one we named hello.py, let’s see how we can run code that was made in the GUI at the command line level. STEP 1 When you first installed Python, the installation routine automatically included all the necessary components to allow the execution of code outside of the GUI IDLE; in other words, the command line. To begin with, click on the Windows Start Button, and type: cmd. STEP 2 As you did when launching the Python IDLE, click on the returned result from the search, the Command Prompt App. This will launch a new window, with a black background and white text. This is the command line, also called a Terminal in macOS, Linux, and Raspberry Pi…

FUNKY FUNCTIONS A function is a command that you enter into Python in order to do something. It’s a little piece of self-contained code that takes data, works on it, and then returns the result. STEP 1 It’s not only data that a function works on. Functions can do all manner of useful things in Python, such as sort data, change items from one format to another, and check the length or type of items. Basically, a function is a short word followed by brackets. For example, len(), list(), or type(). STEP 2 A function takes data, usually a variable, works on it depending on what the function is programmed to do, and returns the end value. The data being worked on goes inside the brackets, so if you wanted…

Did you know that Windows has its own built-in scripting language? Batch files have been around since the early days of Windows, and while they are overshadowed by the might of Windows’ modern graphical user interface, they are still there and still just as capable as they were thirty years ago. Batch file programming is a skill that system administrators still use, so it’s worth spending a bit of time learning how they work, and what you can do with them. This section introduces batch files, and covers user interactions, variables, loops and even a batch file quiz game to inject an element of fun.…

SEARCHING FOR FILES Here’s an interesting little batch file that you can easily extend for your own use. It asks the user for a file type to search for and displays the results. STEP 1 We are introducing a couple of new commands into the mix here but we think they’re really useful. Create a new batch file called seek.bat and in it put: STEP 2 The new command in this instance is color (Americanised spelling). Color, as you already assume, changes the colour of the command prompt display. The color attributes are specified by two hex digits, the first corresponds to the background colour of the Command console and the second to the foreground, and can be any of the following values: STEP 3 Now let’s extend the seek.bat…

Linux is such a versatile operating system that’s both malleable and powerful, while offering the programmer a perfect foundation on which to build their skills. While all the popular and mainstream programming languages are available on Linux, as they are on Windows and macOS, Linux also utilises its own coding language, called scripting. Bash scripting on Linux can be used to create a wealth of useful, real-world programs that interact with the user, or simply work in the background based on a pre-defined schedule. Scripting is a powerful interface to the Linux system, so we’ve crafted this section to help you get to grips with how everything fits together, and how to make some amazing Linux scripts.…

MINTY INGREDIENTS Here’s what you’ll need to install and run Linux Mint as we work through this book. You have several choices available, so take your time and see which works best for you. SYSTEM REQUIREMENTS The minimum system requirements for Linux Mint are as follows: CPU 700MHz RAM 512MB Hard Drive Space 9GB (20GB recommended) Monitor 1024 x 768 resolution Obviously the better the system you have, the better and quicker the experience will be. USB INSTALLATION You can install Linux Mint onto your computer via USB or DVD. We’ll look into each a little later on, but if you’re already familiar with the process (or you’re thinking of USB and just gathering the hardware you’ll need), then you’re going to need a minimum 4GB USB flash drive/stick to…

GOING VIRTUAL Using a Virtual Machine (VM) will take resources from your computer: memory, hard drive space, processor usage and so on. So make sure you’ve got enough of each before commencing. STEP 1 We’re using VirtualBox in this instance, as it’s one of the easiest virtual environments to get to grips with. Enter www.virtualbox.org and click on ‘Download VirtualBox’. This will take you to the main download page. Locate the correct host for your system: Windows or Mac – the Host is the current installed operating system and click the link to begin the download. STEP 2 Next, while still at the VirtualBox download page, locate the VirtualBox Extension Pack link. The Extension Pack supports USB devices, as well as numerous other extras that can help make the VM…

GET SCRIPTING A Bash script is simply a series of commands that Mint will run through to complete a certain task. They can be simple or remarkably complex, it all depends on the situation. STEP 1 You’ll be working within the Terminal and with a text editor throughout the coming pages. There are alternatives to the text editor, which we’ll look at in a moment but for the sake of ease, we’ll be doing our examples in Xed. Before you begin, however, run through the customary update check: sudo apt-get update && sudo apt-get upgrade. STEP 2 There are several text editors we can use to create a Bash script: Xed, Vi, Nano, Vim, GNU Emacs and so on. In the end it all comes down to personal preference. Our…

To help you on your way to becoming a better coder, we’ve included some great coding projects and ideas that you can apply to your own code, use as a demo for those who are starting to code, or improve and send out into the coding community. Want to learn how to craft some retro code? How about learning how to code a text adventure? These and more are all found in this final section. No matter where you go next in coding, whether it’s on to learning more languages, creating amazing apps and games, or helping out and teaching new coders to avoid the pitfalls you made, remember the basics, and have fun! From here, it’s down to you and your imagination. So dream it, and code it.…

LOAD”” Back in the 80s, in the 8-bit home computing era, loading screens were often used to display the cover of a game as it loaded from tape. The image would load itself in, usually one-line-at-a-time, then proceed to colour itself in while the loading raster bars danced around in the borders of the screen. Loading screens were a part of the package and often the buy-in for the whole game as an experience. Some loading screens featured animations, or a countdown for time remaining as the game loads, while others even went so far as to include some kind of playable game. The point being: a loading screen is not just an artistic part of computing history, but an introduction to the program that’s about to be run. While…

THE GOLDEN ERA OF CODE While it may seem a little counterproductive to learn how to code in a language that’s virtually obsolete, there are some surprising benefits to getting your hands dirty with a bit of retro coding. Firstly, learning old code will help you build the structure of code as, regardless of whether it is a language that was developed yesterday, or forty years ago, code still demands strict discipline to work correctly. Secondly, everyday coding elements, such as loops, sub routines and so on, are a great visual aid to learn in older code, especially BASIC. Lastly, it’s simply good fun. GOING BASIC The easiest retro language to play around with is, without doubt, BASIC. Developed back in the mid-sixties, BASIC (Beginner’s All- Purpose Symbolic Instruction Code)…

“It’s up to you how far to take your coding adventure!” MORE THAN CODE For those of you old enough to remember the ‘80s, the golden era of home computing, the world of computing was a very different scene to how it is today. 8-bit computers that you could purchase as a whole, as opposed to being in kit form and you having to solder the parts together, were the stuff of dreams; and getting your hands on one was sheer bliss contained within a large plastic box. However, it wasn’t so much the new technology that computers then offered, moreover it was the fact that for the first time ever, you could control what was being viewed on the ‘television’. Instead of simply playing one of the thousands of…

Coding can be one of those experiences that sounds fantastic, but is often confusing to tackle. After all, there’s a plethora of languages to choose from, countless apps that will enable you to code in a specific, or range, of languages and an equally huge amount of third-party software to consider. In addition, by accessing the Internet, you will discover that there are countless coding tutorials available for the language in which you’ve decided you want to program, alongside even more examples of code. It’s all a little too much at first. The trick is to slow down and, to begin with, not look too deeply into coding. Like all good projects, you need a solid foundation on which to build your skillset and to have all the necessary tools…

CODE::BLOCKS Code::Blocks is a free C++, C and Fortran IDE that is feature rich and easily extendible with plugins. It’s easy to use, comes with a compiler and has a vibrant community behind it too. STEP 1 Start by visiting the Code::Blocks download site, at www.codeblocks.org/downloads. From there, click on the ‘Download the binary releases’ link to be taken to the latest downloadable version for Windows. STEP 2 There you can see, there are several Windows versions available. The one you want to download has mingw-setup.exe at the end of the current version number. At the time of writing this is: codeblocks-17.12mingw-setup.exe. The difference is that the mingw-setup version includes a C++ compiler and debugger from TDM-GCC (a compiler suite). STEP 3 When you’ve located the file, click on the…

DEVELOPING C++ Here are ten great C++ IDEs that are worth looking into. You can install one or all of them if you like, but find the one that works best for you. ECLIPSE Eclipse is a hugely popular C++ IDE that offers the programmer a wealth of features. It has a great, clean interface, is easy to use and available for Windows, Linux and Mac. Head over to www.eclipse.org/downloads/ to download the latest version. If you’re stuck, click the Need Help link for more information. GNAT The GNAT Programming Studio (GPS) is a powerful and intuitive IDE that supports testing, debugging and code analysis. The Community Edition is free, whereas the Pro version costs; however, the Community Edition is available for Windows, Mac, Linux and even the Raspberry Pi.…

GREETINGS FROM C++ Compiling and executing C++ code from Code::Blocks is extraordinarily easy; it’s just a matter of clicking an icon and seeing the result. Here’s how it’s done. STEP 1 Open Code::Blocks, if you haven’t already, and load up the previously saved Hello World code you created. Ensure that there are no visible errors, such as missing semicolons at the end of the std::cout line. STEP 2 If your code is looking similar to the one in our screenshot, then look to the menu bar along the top of the screen. Under the Fortran entry in the topmost menu you can see a group of icons: a yellow cog, green play button and a cog/play button together. These are Build, Run, Build and Run functions. STEP 3 Start by…

THE VALUE OF DATA There are many different data types available for the programmer in C++, such as an integer, floating point, Boolean, character and so on. It’s widely accepted that there are seven basic data types, often called Primitive Built-in Types; however, you can create your own data types should the need ever arise within your code. The seven basic data types are: TYPE COMMAND Integer Integer Floating Point float Character char Boolean bool Double Floating Point double Wide Character wchar_t No Value void These basic types can also be extended using the following modifiers: Long, Short, Signed and Unsigned. Basically this means the modifiers can expand the minimum and maximum range values for each data type. For example, the int data type has a default value range of-2147483648…

HELLO, DAVE You have already used cout, the standard output stream, throughout our code. Now you’re going to be using cin, the standard input stream, to prompt a user response. STEP 1 Anything that you want the user to input into the program needs to be stored somewhere in the system memory, so it can be retrieved and used. Therefore, any input must first be declared as a variable, so it’s ready to be used by the user. Start by creating a blank C++ file with headers. STEP 2 The data type of the variable must also match the type of input you want from the user. For example, to ask a user their age, you would use an integer like this: STEP 3 The cin command works in the…

Python’s ability to create highly readable code, within a small set of instructions, has a considerable impact on our modern digital world. From being an ideal first programmers’ choice through to being able to create interactive stories and games; from scientific applications through to artificial Intelligence and web-based applications, the only limit to Python is the imagination of the person coding in it. It’s Python’s malleable design that makes it an ideal language for many different situations and roles. Even certain aspects of the coding world that require more efficient code still use Python. For example, NASA utilises Python both as a stand-alone language and as a bridge between other programming languages. This way, NASA scientists and engineers are able to get to the data they need without having to…

PYTHON POWER Python is a high-level, general-purpose programming language that was designed by Guido van Rossum in the late ‘80s, as a successor to the ABC Programming Language, and became available to use in 1990. Guido van Rossum, the designer of Python. The Python Software Foundation, a non-profit organisation devoted to both furthering and improving Python, currently develops the language. The foundation’s purpose is to “promote, protect, and advance the Python programming language, and to support and facilitate the growth of a diverse and international community of Python programmers.” The structure of Python code has been designed to flow easily, allowing those who are just beginning to code to follow it without too much difficulty. Yet, despite its ease of use, Python is regularly used throughout a number of industries…

THE POWER OF PI While having a far more powerful coding platform on which to write and test your code is ideal, it’s not often feasible. Most of us are unable to jump into a several hundred-pound investment when we’re starting off and this is where the Raspberry Pi can help out. While having a far more powerful coding platform on which to write and test your code is ideal, it’s not often feasible. Most of us are unable to jump into a several hundred-pound investment when we’re starting off and this is where the Raspberry Pi can help out. The Raspberry Pi is a fantastic piece of modern hardware that has created, or rather re-created, the fascination we once all had about computers, how they work, how to code…

If you’ve previously used Python 3 on a Mac or Linux, and subsequently the Raspberry Pi, you may be a little confused as to why the Windows version of Python uses the command line: python, instead of python3. The reason behind this is that UNIX-like systems, such as macOS and Linux, already have Python libraries pre-installed. These older libraries are present because some of the macOS and Linux system utilities rely on Python 2, and therefore installing a newer version of Python, and thus altering the executable name, could have dire consequences to the system. As a result, developers decided that the best approach for macOS and Linux systems would be to leave the command line ‘python’ as exclusive Python 2 use, and newer versions of user-installed Python would be…

VARIOUS VARIABLES We’ll be working with the Python 3 IDLE Shell in this tutorial. If you haven’t already, open Python 3 or close down the previous IDLE Shell to clear up any old code. STEP 1 In some programming languages, you’re required to use a dollar sign to denote a string, which is a variable made up of multiple characters, such as a name of a person. In Python this isn’t necessary, so, for example, in the Shell enter: name=”David Hayward” (use your own name, unless you’re also called David Hayward). STEP 2 You can check the type of variable in use by issuing the type () command, placing the name of the variable inside the brackets. In our example, this would be: type (name). Add a new string variable:…

COUNTERS Creating code that counts in increasing or decreasing number sets is great for demonstrating loops. With that in mind, let’s look at the If statement a little more, alongside more variables, and introduce the Else, Timeout and eof (End of File) commands. STEP 1 Start by creating a new batch file called count.bat. Enter the following, save it and run: STEP 2 The count. bat code starts at number one and counts, scrolling down the screen, until it reaches 100. The Timeout command leaves a one second gap between numbers and the Else statement continues until the counter variable equals 100 before going to the eof (End Of File), thus closing the loop. STEP 3 The count.bat is a rough way of demonstrating a loop; a better approach would…

DVD BOOTABLE MEDIA We’re using a Windows 10 PC here to transfer the ISO to a DVD. As long as you’re using a version of Windows from 7 onward, the process is extremely easy. STEP 1 First locate the ISO image of Linux you’ve already downloaded. In Windows 7, 8.1 and 10 computers, you’ll usually find this in the Downloads folder unless, when saving it, you’ve specified a different location. STEP 2 Next, insert a recordable DVD disc into your computer’s optical drive. After a few seconds, while the disc is read, Windows will display a pop-up message asking you what to do with the newly inserted disc, ignore this as we’re going to use the built-in image burning function. STEP 3 Right-click the Linux ISO and from the menu…

CREATING THE VM There are plenty of options to choose from when creating a VM. For now though, we’ll setup a VM adequate to run the excellent Linux Mint, and perform well. STEP 1 With VirtualBox open, click on the New icon in the top-middle of the right-hand panel of the app. This will open the new VM Wizard. STEP 2 In the box next to Name type Linux Mint, and VirtualBox should automatically choose Linux as the Type and Ubuntu (64-bit) as the Version, if not then use the drop-down boxes to select the correct settings (remember Mint mainstream is based on Ubuntu). Click Next when you’re ready to proceed. STEP 3 The next section will define the amount of system memory, or RAM, the VM has allocated. Remember…

VARIABLES Just as in every other programming language a Bash script can store and call certain variables from the system, either generic or user created. STEP 1 Let’s start by creating a new script called hello.sh; xed hello.sh. In it enter: #!/bin/bash, then, echo Hello $1. Save the file and exit Xed. Back in the Terminal make the script executable with: chmod +x hello.sh. STEP 2 As the script is now executable, run it with ./hello.sh. Now, as you probably expected a simple ‘Hello’ is displayed in the Terminal. However, if you then issue the command with a variable, it begins to get interesting. For example, try ./hello.sh David. STEP 3 The output now will be Hello David. This is because Bash automatically assigns variables for the user, which are…

EASY AUTOMATION AND HANDY SCRIPTS Are you entering line after line of commands to retrieve system information, find a file or rename a batch of files? A script is a better answer. STEP 1 Let’s start by creating a script to help display the Mint system information; always a handy thing to have. Create a new script called sysinfo.sh and enter the following into Xed, or the text editor of your choice. STEP 2 We’ve included a couple of extra commands in this script. The first is the -e extension for echo, this means it’ll enable echo interpretation of additional instances of a new line, as well as other special characters. The proceeding ‘31;43m’ element enables colour for foreground and background. STEP 3 Each of the sections runs a different…

You will find that nearly all the professional developers out there will set aside some time to plan out how their code is going to fit into the wider project on which they’re working. Regardless of whether they’re working as part of a team on the latest game, developing a workflow user interface for the company, or creating a set of automated tasks that can be used across a number of different platforms, each developer will set out their code in a plan. The planning stages can be unique to the developer, unique to the company for which they’re working, or the project on which they’re working. Planning meetings will often sketch out a rough plan of how the end product will function, with each developer team then working on…

If you can think back to some of the classic text adventures you may have played in the past, consider the amount of work that was needed to get them up and running. If you’re not familiar with a text adventure, then open a browser and go to http://textadventures. co.uk/games/play/5zyoqrsugeopel3ffhz_vq. This is an online version of the classic text adventure Zork. Zork was created for the DEC PDP- 10 workstations, using the MDL programming language back in the late seventies. Despite its age, it’s still considered one of the best text adventures to play. INGREDIENTS FOR A COMPELLING ADVENTURE The first ingredient is a story, a plot that will take the player on a ride through their own imagination. It doesn’t necessarily have to include dragons, barbarians, spaceships, or other…

THE FINAL COUNTDOWN Let’s begin with some example code that will display a large countdown from ten, then clear the screen and display a message. The code itself is quite simple, but lengthy. You will need to start by importing the OS and Time modules, then start creating functions that display the numbers (see image below) and so on to 10. It’ll take some time, but it’s worth it in the end. Of course, you can always take a different approach and design the numbers yourself. The next step of the process is to initialise the code settings and start the countdown: The code in its entirety can be viewed from within our Code Repository: bdmpublications.com/code-portal, where you’re free to copy it to your own Python IDLE and use it…

DEF BEGINNER(MISTAKES=10) Here are ten common Python programming mistakes most beginners find themselves making. Being able to identify these mistakes will save you headaches in the future. VERSIONS To add to the confusion that most beginners already face when coming into programming, Python has two live versions of its language available to download and use. There is Python version 2.7.x and Python 3.6.x. The 3.6.x version is the most recent, and the one we’d recommend starting. But, version 2.7.x code doesn’t always work with 3.6.x code and vice versa. THE INTERNET Every programmer has and does at some point go on the Internet and copy some code to insert into their own routines. There’s nothing wrong with using others’ code, but you need to know how the code works and…