Introduction I was recently tasked with modifying a Dyalog class currently running under Dyalog 16 so that it would run under Dyalog 17.1. The class in question was used to serialize APL data into a JSON format and back again. The problem was that it made use of the two I-beams 7159 and 7160. These are deprecated in 17.1 so … Read More

As well as being a programmer, I am a hobbyist musician. At school and in my spare time I have studied music production and music theory. I occasionally write pieces of music and I recently received a MIDI controller as a gift. Being a programmer one of my initial thoughts was ‘how can I code an interface to this device?’, … Read More

The Spring Mini Conference For the past twelve years the British APL Association’s (of which I’m the Editor and Optima Systems MD Paul Grosvenor is the Chairman) London group has been holding a regular symposium on the last Friday of the month only skipping December and the odd date that clashed with a royal wedding to avoid the crowd. This … Read More

Recently we had a special date on the calendar, that some of you may have noticed. The date in question is February 2nd 2020, which when written in any of these formats: DD/MM/YYYY (UK), MM/DD/YYYY (US) or YYYYMMDD (ISO), is in fact a palindrome (excluding ‘/’ or other symbols). This made me think about how I could check for palindromes … Read More

Version management is a vital component of any software development project. The ability to revert to previous version of a project in the case of disastrous bug or misguided feature is one that any developer is glad to have in their back pocket. A source code manager (SCM) is software that assists in managing and versioning source code. Programmers use … Read More

Dyalog APL offers two symbols which do, on the surface, a seemingly pointless task. I’m referring to left tack (⊣) and right tack (⊢). As with most APL functions, they have two uses depending on their number of arguments: monadic, if used only with a right argument; or dyadic if used with a left and a right argument. If used … Read More

I had a question for the team in our regular meeting on Wednesday, but it relied on an understanding on squad indexing, and nobody felt comfortable enough with ⌷ to answer my question. I’ve since reach a conclusion and thought I’d share. For a given 3-dimensional object, I can use square bracket indexing to retrieve the indices I want. I … Read More

APL began life as a mathematical notation, created by the Canadian computer scientist Kenneth E. Iverson. Over the years it evolved into the APL programming language. There are several versions of APL but they all follow the same order of operations. When I started learning APL, one of the trickiest things was reprogramming my brain! This was because APL does … Read More

The APL programming language celebrated its 50th anniversary in 2016. Since its inception the APL language has evolved a growing and rich functionality. An interpreted language with an interactive development environment APL has an immediate fingertip feedback for the developer working with it. Features that combine to provide a fertile and creative environment for its programmers. In the early days … Read More

The FinnAPL meeting this year is hosted just outside Helsinki in Hämeenkylä Manor. Arriving at the manor the night before I couldn’t appreciate the beautiful setting until I woke up this morning to a snow covered landscape all around from my room’s view. The seminar was formally opened by Veli-Matti Jantunen who welcomed us all before diving straight into the … Read More

A talk at the Dyalog ’17 User Meeting that I must admit wasn’t on my radar, took me by surprise and really caught my attention. The talk was from Gilgamesh Athoraya of Data Analytics AB, and it was about Evolutionary Programming. The talk was a detailed take on using artificial neural networks to enable your programs to evolve. This is … Read More

One of the things I was most looking forward to at Dyalog ’17 was Marinus Oosters’ presentation of Py’n’APL. I caught a brief glimpse of his work on a webinar beforehand, and it was enough to inspire me to start learning Python in my spare time. Py’n’APL is a bridge between Python and APL; It allows you to execute Python … Read More

This post describes the thought process I went through and technical decisions I made during the development of APL CodeGolf. The whole development started with an idea my colleague floated around a month before the conference. Sam Gutsell suggested it might be a good idea to run a code golf competition in which delegates could compete to get the tersest … Read More

Dyalog does a great job of filling their user meetings with interesting presentations, and this year was no different. Personally, I find that the challenge then becomes for the attendees to soak in as much as possible without getting overwhelmed by the ocean of information: As if it wasn’t enough of a challenge, the last day of the meetings follows … Read More