ok VS april

This - https://github.com/JohnEarnest/ok - can also be used sometimes...

If you want to try out K, there are some open source implementations, like John Earnest's oK which has a REPL and a calculator-like interface for mobile phones with a charting feature.

and have the programmer use the word "barchart", they instead prefer to use the definition itself. The word "barchart" has a specific meaning (here, an ascii "bar chart" of 0s and 1s, showing the relative sizes of the values of input array x), but "{x>\:!|/x}" might be useful for more than just bar charts. This idiom contains smaller idioms like "count til max" (!|/) which in turn contains "max" (|/).

Being able to see the code makes it easier to explore and tweak to your specific needs. But more importantly, there are no "official" names for concepts like "count til max". That's just my personal name for it. A python programmer would call it "range". You could come up with your own name for (!|/) that makes perfect sense to you. But that name will probably be longer than its definition, and less flexible.

[1] https://github.com/JohnEarnest/ok/blob/gh-pages/examples/idi...

check out oK[0] by John Earnest, who is the author of the content of this post

it is well-written manual and is a great jumping off point

there is a k-enthusiast element.io server[1] where you can ask any question you like. folks are friendly!

[0] https://github.com/JohnEarnest/ok

[1] https://matrix.to/#/#aplfarm-k:matrix.org

There are attempts to combine those...

April (Array Programming Re-Imagined in Lisp)

https://github.com/phantomics/april

> operations that apply to the whole array

like MAP and REDUCE, higher order functions are not really new to Lisp. In Common Lisp they are extended to vectors.

> list languages and array languages are quite different.

There are some common things like interactive use, functional flavor, etc.

There's also April APL: https://github.com/phantomics/april

Also the array language family seems to be stronger than ever with foss: ngn/k, BQN, uiua, and of course J but as you mentioned they're all different languages.

I love J and APL, but April takes the cake for me[1]. APL in Lisp.

I also prefer SPARK2014 instead of Rust if I am not going to use C. I've started learning Rust a few times. SPARK2014 is easier to get going for me, and it has been used to produce high-integrity software and real-world applications for over a decade, and more if you include Ada from which it sprang[2].

[1] https://github.com/phantomics/april

[2] https://www.adacore.com/about-spark

The one big use case was RabbitMQ in a messaging app, not HFT. I doubt Elixir even with Nx can compete with low-level HFT code. Python DL/ML code libraries are just wrappers around C too. Maybe if BeamAsm and Nx are used Elixir could be used for more numerical or not just distributed applications.

I've programmed in Python and Julia, and when I worked at an engineering (mechanical, entertainment engineering) company, Julia was great for its similarity to Matlab. I am a self-taught engineer, so I did not get pulled into Matlab in college.

Personally, I took to Erlang, so I could write plugins for Wings3D back in the early 2000s, but I never stuck with Erlang, or Wings3D (Blender3D was my choice and I even contributed to have it go opensource way back when). I like Erlang's syntax better for some reason, although Elixir's is beautiful too. I was not a Ruby programmer, and I had delved into Haskell and Prolog, so I think Erlang made more sense to me. I think Elixir has a lot more momentum behind it than Erlang, but at the root it's Erlang, so I think I'll stick with Erlang for BEAM apps. My favorite language is April[1] (APL in Lisp), and given my love of J, would be a better fit for any finance apps I might write. I am trying to convert some of the Lisp code in this book, "Professional Automated Trading: Theory and Practice" to April.

Maybe I'll write some equivalent Elixir code to compare.

[1] https://github.com/phantomics/april

I'm also very curious for hear from expert lispers. I've tried to find the sweat spot where lisp would fit better than what I already know: shell for glue and file ops, R for data munging and vis, python to not reinvent things, perl/core-utils for one liners. But before I can find the niche, I get turned off by the amount of ceremony -- or maybe just how different the state and edit/evaluate loop is.

I'm holding onto some things that make common lisp look exciting and useful (static typing[0], APL DSL[1], speed [2,3,4]) and really want to get familiar with structural editing [5]

[0] https://github.com/phantomics/april - APL dsl

The 2 0 at the start of the APL line above controls the mirroring behavior. The second number can be set to 0 or 1 to choose which side of the image to mirror, while the 2 sets the axis along which to mirror. This will be 1 or 2 for a raster image but this function can mirror any rank of array on any axis.

April was used to teach image filtering in a programming class for middle-schoolers, you can see a summary in this video: https://vimeo.com/504928819

For more APL-driven graphics, April's repo includes an ncurses demo featuring a convolution kernel powered by ⌺, the stencil operator: https://github.com/phantomics/april/tree/master/demos/ncurse...

#1: Thanks to J, I was able to get in the global Top 100 in the first day of Advent of Code. I've never done this before and I'm feeling a bit emotional. Thanks, J. #2: April 1.0 Is Released | 4 comments #3: BQNPAD — a BQN REPL with syntax highlighting and live evaluation preview | 8 comments

APL + Lisp =

https://github.com/phantomics/april/ and yes it is used in production©!

> What pushed the development of April really is that April is used by a hardware startup called Bloxl (of which I am the CTO). There are other users but Bloxl is the flagship application.

https://www.arraycast.com/episodes/episode23-andrew-sengul

Bloxl in use: https://user-images.githubusercontent.com/3721004/159686845-... See also the ELS conference 2022.