Don’t Object To Python Objects

May 2, 2024 by Al Williams 24 Comments

There’s the old joke about 10 kinds of programmers, but the truth is when it comes to programming, there are often people who make tools and people who use tools. The Arduino system is a good example of this. Most people use it like a C compiler. However, it really uses C++, and if you want to provide “things” to the tool users, you need to create objects. For example, when you put Serial in a program, you use an object someone else wrote. Python — and things like Micropython — have the same kind of division. Python started as a scripting language, but it has added object features, allowing a rich set of tools for scripters to use. [Damilola Oladele] shows the ins and outs of object-oriented Python in a recent post.

Like other languages, Python allows you to organize functions and data into classes and then create instances that belong to that class. Class hierarchies are handy for reusing code, customizing behavior, and — through polymorphism — building device driver-like architectures.

Continue reading “Don’t Object To Python Objects” →

Programming Ada: Packages And Command Line Applications

May 1, 2024 by Maya Posch 5 Comments

In the previous installment in this series we looked at how to set up an Ada development environment, and how to compile and run a simple Ada application. Building upon this foundation, we will now look at how to create more complex applications, along with how to parse and use arguments passed to Ada applications on the command line (CLI). After all, passing flags and strings to CLI applications when we launch them is a crucial part of user interaction, as well as when automating systems as is the case with system services.

The way that a program is built-up is also essential, as well-organized code eases maintenance and promotes code reusability through e.g. modularity. In Ada you can organize subprograms (i.e. functions and procedures) in a declarative fashion as stand-alone units, as well as embed subprograms in other subprograms. Another option is packages, which roughly correspond to C++ namespaces, while tagged types are the equivalent of classes. In the previous article we already saw the use of a package, when we used the Ada.Text_IO package to output text to the CLI. In this article we’ll look at how to write our own alongside handling command line input, after a word about the role of the binding phase during the building of an Ada application.

Continue reading “Programming Ada: Packages And Command Line Applications” →

Train A GPT-2 LLM, Using Only Pure C Code

April 28, 2024 by Donald Papp 7 Comments

[Andrej Karpathy] recently released llm.c, a project that focuses on LLM training in pure C, once again showing that working with these tools isn’t necessarily reliant on sprawling development environments. GPT-2 may be older but is perfectly relevant, being the granddaddy of modern LLMs (large language models) with a clear heritage to more modern offerings.

LLMs are fantastically good at communicating despite not actually knowing what they are saying, and training them usually relies on PyTorch deep learning library, itself written in Python. llm.c takes a simpler approach by implementing the neural network training algorithm for GPT-2 directly. The result is highly focused and surprisingly short: about a thousand lines of C in a single file. It is a highly elegant process that does the same thing the bigger, clunkier methods accomplish. It can run entirely on a CPU, or it can take advantage of GPU acceleration, where available.

This isn’t the first time [Andrej Karpathy] has bent his considerable skills and understanding towards boiling down these sorts of concepts into bare-bones implementations. We previously covered a project of his that is the “hello world” of GPT, a tiny model that predicts the next bit in a given sequence and offers low-level insight into just how GPT (generative pre-trained transformer) models work.

The Performance Impact Of C++’s `final` Keyword For Optimization

April 24, 2024 by Maya Posch 22 Comments

In the world of software development the term ‘optimization’ is generally reason for experienced developers to start feeling decidedly nervous, especially when a feature is marked as an ‘easy and free optimization’. The final keyword introduced in C++11 is one of such features. It promises a way to speed up object-oriented code by omitting the vtable call indirection by marking a class or member function as – unsurprisingly – final, meaning that it cannot be inherited from or overridden. Inspired by this promise, [Benjamin Summerton] figured that he’d run a range of benchmarks to see what performance uplift he’d get on his ray tracing project.

To be as thorough as possible, the tests were run on three different systems, including 64-bit Intel and AMD systems, as well as on Apple Silicon (M1). For the compilers various versions of GCC (12.x, 13.x), as well as Clang (15, 17) and MSVC (17) were employed, with rather interesting results for final versus no final tests. Clang was probably the biggest surprise, as with the keyword added, performance with Clang-generated code absolutely tanked. MSVC was a mixed bag, as were the GCC versions other than GCC 13.2 on AMD Ryzen, which saw a bump of a few percent faster.

Ultimately, it seems that there’s no free lunch as usual, and adding final to your code falls distinctly under ‘only use it if you know what you’re doing’. As things stand, the resulting behavior seems wildly inconsistent.

FLOSS Weekly Episode 780: Zoneminder — Better Call Randal

April 23, 2024 by Jonathan Bennett 3 Comments

This week Jonathan Bennett and Aaron Newcomb chat with Isaac Connor about Zoneminder! That’s the project that’s working to store and deliver all the bits from security cameras — but the CCTV world has changed a lot since Zoneminder first started, over 20 years ago. The project is working hard to keep up, with machine learning object detection, WebRTC, and more. Isaac talks a bit about developer burnout, and a case or two over the years where an aggressive contributor seems suspicious in retrospect. And when is the next stable version of Zoneminder coming out, anyway?

Continue reading “FLOSS Weekly Episode 780: Zoneminder — Better Call Randal” →

Programming Ada: First Steps On The Desktop

April 23, 2024 by Maya Posch 66 Comments

Who doesn’t want to use a programming language that is designed to be reliable, straightforward to learn and also happens to be certified for everything from avionics to rockets and ICBMs? Despite Ada’s strong roots and impressive legacy, it has the reputation among the average hobbyist of being ‘complicated’ and ‘obscure’, yet this couldn’t be further from the truth, as previously explained. In fact, anyone who has some or even no programming experience can learn Ada, as the very premise of Ada is that it removes complexity and ambiguity from programming.

In this first part of a series, we will be looking at getting up and running with a basic desktop development environment on Windows and Linux, and run through some Ada code that gets one familiarized with the syntax and basic principles of the Ada syntax. As for the used Ada version, we will be targeting Ada 2012, as the newer Ada 2022 standard was only just approved in 2023 and doesn’t change anything significant for our purposes.

Continue reading “Programming Ada: First Steps On The Desktop” →

Compiling And Running Turbo Pascal In The Browser

April 17, 2024 by Maya Posch 15 Comments

When a friend of [Lawrence Kesteloot] found a stack of 3.5″ floppy disks, they found that it contained Turbo Pascal code which the two of them had worked on back in the Summer of 1989. Amidst reminiscing about the High School days and watching movies on VHS, [Lawrence] sought a way to bring these graphical applications once more back to life. Not finding an easy way to compile Turbo Pascal code on Mac even back in 2013 when he started the project, he ended up writing a Turbo Pascal compiler in JavaScript, as any reasonable person would do in this situation.

SPIDER.PAS in its full glory. (Credit: Lawrence Kesteloot)

As noted by [Lawrence], the compiler doesn’t implement the full Turbo Pascal 5.5 language, but only the subset that was required to compile and run these applications which they had found on the floppy disks. These include ROSE.PAS and SPIDER.PAS along with three others, and can also be found in the GitHub repository. As can be seen in the online version of the compiler, it captures the feel of programming Pascal in 1989 on the command line.

Naturally, the software situation has changed somewhat over the last decade. We’ve recently seen some promising multi-platform Pascal compilers, and of course you could even run Turbo Pascal in DOSBox or similar. That might make this project seem irrelevant, but being able to write and run Pascal applications in more ways and on more platforms is never a bad thing.