Author Archives: Richard Park

Taking Back Ctrl: Keyboard Shortcuts in the Dyalog IDEs

Posted on by
Reply

In this blog post post I describe:

  • how to use standard Ctrl keyboard shortcuts when using Dyalog on all platforms.
  • little-known APL input features for Microsoft Windows.
  • alternative input methods that do not use the Ctrl key for APL input.

I don’t personally use the official Dyalog IME for Microsoft Windows as my daily APL input method. My only complaints are that it forces me to use the Ctrl key for APL input, which conflicts with conventional shortcuts for most applications, and for some reason it puts an additional item in my input method list because I have a Japanese input enabled, even though that is not a supported layout for the IME!

I am a fan of Adám’s AltGr keyboard for Windows for a couple of reasons. It is based on the Microsoft Keyboard Layout Creator (MSKLC), and appears to work in newer Universal Windows Platform (UWP) apps and with the default On-Screen Keyboard on Windows. It also has accents and box-drawing characters. However, support might be unreliable, because Microsoft do not officially support MSKLC on Windows 11, and there are rumoured issues with using it on ARM machines. Its main drawback is the limited choice of shifting keys, which can make it difficult to use with certain keyboard layouts or in certain applications. Personally, I am fond of using Caps Lock as my primary APL shifting key, because it is rare these days that I need to TYPE A BUNCH OF THINGS IN ALL CAPITALS – it feels like shouting.

I used to do this by mapping Caps Lock to Alt Gr through some registry trickery. However, Kanata allows me to use almost any keys I like. I now have Caps Lock and Right Ctrl as APL shifting keys. In addition, I can double-tap Caps Lock to toggle it, so I can SHOUT OVER TEXT if I really need to. It’s cross-platform, so my single APL Kanata configuration gives me a consistent experience even when using my Linux virtual machine. There are still many features on my wish list for a comprehensive input method editor, but this is quite good for now (I wonder if anybody is able to adapt mozc for APL?).

Whichever keyboard input method you use, once you are not using Ctrl for APL input you will be very glad to get back your beloved, conventional keyboard shortcuts for use in the Dyalog editor.

In the Dyalog IDE for Microsoft Windows, you can set keyboard shortcuts by selecting Options > Configure in the Session’s menu bar, then selecting the Keyboard Shortcuts tab. From here, you can click on a code that corresponds to an action for which you want to set a shortcut.

Dyalog IME for Microsoft Windows Configuration Dialog

These are keyboard shortcuts recognised by the Dyalog development environment.

I set:

  • <FX> to Ctrl+S to save changes in the editor without closing it
  • <SA> to Ctrl+A to select all text in a window
  • <CP> to Ctrl+C to copy text
  • <CT> to Ctrl+X to cut text
  • <PT> to Ctrl+V to paste text
  • <SC> to Ctrl+F to search and find text in the session log, editor, and debugger
  • <RP> to Ctrl+H to search and replace text in the session log, editor, and debugger

To help find these in the list, click on the Code column title to put them in alphabetical order.

In Ride, only <FX> needs to be set, as the other shortcuts should default to this behaviour.

Having said all that, the official Dyalog IME still has features that would be invaluable especially if I were a brand new user. You can read about these in the Dyalog for Microsoft Windows UI guide and configure them using the IDE by going to Options > Configure > Unicode Input > Configure Layout. A little-known tip is that its backtick (also known as introducer or prefix) input method offers a searchable keyword menu, so that you can find glyphs by name or by the name of the function or operator it represents.

After setting the prefix introducer key to # (octothorpe / hash), pressing twice and typing “rot” shows suggestions for the glyphs ⌽ and ⊖ with the keywords “rotate” and “rotatefirst”.

There’s also the wonderful overstrike feature. Once upon a time, APL was executed on remote machines accessed using the IBM Selectric Teletype typewriter; you can see this in this demonstration from 1975. Certain characters would be composed by typing one symbol over another, such as printing a vertical bar (|) over a circle (○) to produce the circle-bar glyph for rotate/reverse (⌽).

Its basic usage is a feature of the IDE for Microsoft Windows; the IME isn’t required at all. If you press the Ins key on your keyboard, it usually toggles “insert” or “overtype” mode. This is typically indicated by the vertical bar text cursor changing into an underbar. Typing will then replace existing text indicated by the cursor. With overstrikes enabled, APL glyphs can be created using other glyphs!

APL Glyph Overstrike Animation

Insert, Slash (/), LeftArrow, Dash (-), Circle (○), LeftArrow, Stile (|)

The IME allows you to use this in applications other than Dyalog by ticking Enable Overstrikes from the IME settings. You can read the documentation to learn more, but the basic mechanism is to use the Overstrike Introducer Key (default Ctrl+Backspace) followed by entering the two symbols to overstrike.

Settings menu for the Dyalog Input Method Editor

For this post I just wanted to highlight aspects of APL input beyond the simple defaults. For more about using your keyboard with Dyalog, see Adám’s blog post about enhanced debugging keys.

Email, RSS Follow

JSM 2025 – Introducing APL and TamStat to Statisticians

Posted on by

Joint Statistical Meetings (JSM) is an annual conference hosted by the American Statistical Association. Last month, Josh, Martina, and I attended JSM 2025 in Nashville, Tennessee, with Professor Stephen Mansour. Josh, Martina, and I were exhibitors, and hosted a stall in the exposition hall alongside other organisations. Steve exhibited TamStat (a free-to-use statistical package written in Dyalog APL) alongside us, but was also an attendee and gave a presentation and a workshop at the conference.

Josh, Stephen, Rich, and Martina at the Dyalog Ltd booth

Our large poster included TamStat as one of several use cases, a visual hook comparing APL with traditional mathematical notation, an example using APL to compute k-means clustering, and information about Dyalog features. It was designed to intrigue people from a distance and encourage them to come closer to read more details. The maths and clustering selected for the poster were chosen based on them being things that statisticians are already familiar with. One person said APL glyphs reminded them of Inuktitut syllabics.

Promotional poster used at JSM 2025

Promotional poster used at JSM 2025

TamStat attracted a lot of interest from both students and teachers. Students were impressed by its simplicity, and some teachers were looking for web browser-based applications because they are easy to access on their institutions’ systems. Steve has distilled core statistical concepts into a very digestible syntax and vocabulary that echoes APL. In his workshop, the students remarked how easily they were able to pick up the syntax and use the graphical interface to solve the exercises.

A sticker on the back window of a car that reads "=>÷"

While driving around the city, we noticed this sticker on a car window. I’m not sure the driver knows that it’s valid APL! Can you tell what it means in English? Can you tell what it does in APL?

On the first night there was an informal event hosted in the exposition hall, including “speed posters” presentations on an array of computer monitors; presenters had only one hour to show their work (as opposed to the larger poster sessions that were a whole morning and afternoon). There was karaoke and refreshments, and exhibitors were in their booths for dicussions. People did come and talk to us, although that wasn’t the main purpose of the evening. Our highlight was seeing Steve’s incredible cover of Your Cheatin’ Heart by Hank Williams.

Twice a day there were large poster sessions where academics were available to explain their research. Many of these centred around assessing various statistical methods, machine learning, and some deep learning methods, especially for high dimensional (lots of parameters, not as in array axes) data or limited available data, and they were often in the context of supporting medical studies. Despite biostatistics being the plurality, there was a range of research on display including statistical methods applied to exoplanet detection (astrophysics), medical studies, and an adventure board game for teaching statistics. Many established statistical software packages were employed – most people used R, although we heard a few cases of Julia being used for heavy computation.

We met so many lovely people during our week in Nashville, and were happy to be able to introduce so many people to Dyalog, APL, and TamStat. We learned a lot about statisticians, their use cases, and their feelings about the software they use. It’s always great showing Dyalog outside the APL community, and even better in person!

————————————

For more information on TamStat, see:

Email, RSS Follow