The APL Orchard

@dzaima most of the time I use rank I either think I know what I'm doing and it fails, or I don't know what I'm doing but it works!

@SJT My day job in knee deep in k8s, docker, and all that jazz. Not exactly sure what kind of consulting you're looking for, but feel free to ping me at xoongeethe at wilsonb.com if you want.

@Fmbalbuena, you will learn much faster by trying to understand on your own. By asking @Adám to help you all the time, you might be giving up the opportunity to push the envelope of your own understanding.

@AndréLeria Why use BQN?: Versus APL and J

why? everyone knows how taylor series work.

@RomillyCocking Reference card

So you've decided to install Dyalog APL? Great. You can download it from here and find out how to fix the keyboarding here.

As a curiosity, I spotted that there was an (extremely minimal; only handles boolean vectors) APL interpreter submitted in 1989 as an entry to IOCCC: ioccc.org/years-spoiler.html (search for APL on the page). The code itself is ioccc.org/1989/robison.c -- 34 lines of C!

Happy new year, APLers.

Announcement: Schedule and registration for APL Seeds '23, the 22 March 2023 (14:00 UTC) free online event aimed at new APLers and the APL-curious (although all are welcome), is now available.

(btw instead of images you could post paste (shameless self-advertisement); SE chat has a message length limit, but that can be worked around by using multiline messages, but then SE chat stops allowing markdown sooo)

Well, because Dyalog hired me ;-) and because it means I can do APL all day while earning enough to sustain my family, and because it is a nice place to work.

- read first 5 chapters or xpqz's book

@FawnLocke You can't win money, but you can win free entry to the next physical user meeting.

Announcement: Dyalog is looking for beta testers for our yearly problem solving competition. While you can use any language to solve the problems, we prefer if you use an APL, or at least an array-oriented language. You will be expected to give feedback on the 10 easy and ≤10 harder problems, while rating their relative difficulties. Note that by beta-testing, you disqualify from the competition. Let me know if you're interested.

Can't wait for 18.2…

I ported my APL solution to numpy. Iverson must be turning in his grave: gist.github.com/xpqz/151a8aa81f5333da9d3d75bb2bb48fee

APL is "hard" language for ppl who are from C++/Java/Python world at the beginning.

Yes. Much easier to teach to non-programmers.

Hello! I'm in the happy position to announce that the first (online) meet of the newly created "APL ∊ BCN" meetup.com group will take place on Saturday 2021-12-18 at 19:00 CET. meetup.com/apl-bcn/events/282411026

Announcement: Most recordings from Dyalog '21 have now been published.

IO stands for Index Origin, it's a system variable that controls, well, the origin of the index :P It determines whether indexing starts at 0 or 1, and it influences primitives like ⍳:

H ← {÷1+∘.+⍨⍳⍵}

You know about the short url apl.chat?

I'm not sure that's really a sweet spot for APL. However, it'd be nice if they had off-the-shelf APL containers for easy deployment of APL-based services.

@milia Have you seen my beginner's guide to APL? xpqz.github.io/learnapl

Savour the moment!

@milia Yes it is, and equivalent to 1+÷1+÷1+÷1+÷…+÷1

As I solve more problems in APL, it feels more and more like a general programming language, almost in the same class with Python, JS, or Haskell.

I like the tacit interior of my favourite APL expression: ⋄ 1 +∘÷⍣≡ 1

@elliptic00 You're absolutely right, but ⌽ precedes the invention of the rank operator by a long time. In fact, originally, Iverson had 64 functions like ⌽ ⍉ ⊖ but it was found that those three were enough to express most things without it becoming too awkward. Just ⌽ and ⍉ would have worked too, but ⍉⌽⍉M to flip vertically was apparently too verbose.

Announcement: apl.show can now be found on many podcast providers, but you can the feed https://apl.show/podcast.rss manually if you cannot find it.

A rare treat: Managed to reduce a 190-line/6.9 kB function to 66 lines/2.3 kB while adding plenty of functionality and fixing various issues.

Announcement: DuckDuckGo now has an !aplcart bang; you can search directly on APLcart by entering !aplcart with your query. This also works in your URL bar if you use DDG as your browser search engine.

My maths teacher asked me about making a numerical integrator in a programming language.... little does he know it's a two liner in APL

kapdemo.dhsdevelopments.com

@Adám or even 1⌽,⍨9⍴'''1⌽,⍨9⍴'''

if I cant recompile my operating system, is it really mine?

@WongJiaHau (Self-)outer product is a common trick to build a matrix with certain symmetry, and the specific output is easy to construct by going through a pyramid

⋄ {2|∘.⌊⍨(⊢⌊⌽)⍳⍵}¨ 3 5 7

@all Quite a mouthful. Any questions? Any brain matter that needs mopping up from the floor?

@rak1507 My phase 1 and 2 answers

@user41805 I will definitely write something on my blog about phase 2 because I really enjoyed it so much; while I don't, here's my phase 1

Hello all, @Bubbler your solutions are so elegant! Mine look so clumsy and verbose in comparison. github.com/rak1507/APL-Competition-2020/blob/master/… These are mine.

My Phase 1/2 solutions