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mpweiher

Zoo of Array Languages ktye.github.io

Pompidou5 hours ago

R is also an array language, but a non-iversonian one. Another good ressource for array languages is https://aplwiki.com/.

r/apljk on reddit is also active.

countrymile2 hours ago

That's my understanding too. R never seems to make these lists.

seanhunter4 hours ago

At one time I briefly spent a bunch of time learning kdb/q. I remember one particular day when I wrote a non-trivial program and it worked first time. I was so shocked I thought I must have suffered some kind of brain aneurism or something.

gcanyon5 hours ago

Array languages are such a mind twist and so fun. I dabbled in J at one point, and I love explaining

+/%#

to people. But the real expressive power comes when you start to get into tacit expressions yourself, understand function exponents, and "get" under.

Hmmm... maybe I need a refresher...

cess115 hours ago

There's an APK, for dabbling on the phone at times when there's no larger computer available but still time to spend.

https://code.jsoftware.com/wiki/Guides/JAndroid

thristian5 hours ago

APL and K are still pretty daunting, but I've recently been dabbling in Lil[1], which is something like a cross between K and Lua. I can fall back on regular procedural code when I need to, but I appreciate being able to do things like:

    127 * sin (range sample_rate)*2*pi*freq_hz/sample_rate

This produces one second audio-clip of a "freq_hz" sine-wave, at the given sample-rate. The "range sample_rate" produces a list of integers from 0 to sample_rate, and all the other multiplications and divisions vectorise to apply to every item in the list. Even the "sin" operator transparently works on a list.

It also took me a little while to get used to the operator precedence (always right-to-left, no matter what), but it does indeed make expressions (and the compiler) simpler. The other thing that impresses me is being able to say:

    maximum:if x > y x else y end

...without grouping symbols around the condition or the statements. Well, I guess "end" is kind of a grouping symbol, but the language feels very clean and concise and fluent.

[1]: https://beyondloom.com/decker/lil.html

fainpul4 hours ago

I assume this is the same as this?

  # python
  [127 * sin(x * tau * freq / samplerate) for x in range(samplerate)]

zahlman4 hours ago

For that matter,

  # python
  from numpy import sin, arange, pi
  127 * sin(arange(samplerate) * 2 * pi * freq / samplerate)

thristian4 hours ago

Pretty much, yeah! The difference is that in Python the function that calculates a single value looks like:

    foo(x)

...while the function that calculates a batch of values looks like:

    [foo(x) for x in somelist]

Meanwhile in Lil (and I'd guess APL and K), the one function works in both situations.

You can get some nice speed-ups in Python by pushing iteration into a list comprehension, because it's more specialised in the byte-code than a for loop. It's a lot easier in Lil, since it often Just Works.

RodgerTheGreat4 hours ago

A few more examples in K and Lil where pervasive implicit iteration is useful, and why their conforming behavior is not equivalent to a simple .map() or a flat comprehension: http://beyondloom.com/blog/conforming.html

leephillips3 hours ago

And in Julia it’s foo.(x).

marcentusch5 hours ago

This is cool. Wish there was more examples for jtye/k so I would have a better chance of learning to use it.

Also missing Uiua.

veridianCrest3 hours ago

Array languages: where your first working program feels like a happy accident.

OneDeuxTriSeiGo3 hours ago

Programming in an array lang "should" generally feel like using a calculator.

You are working in a REPL, starting with small expressions to verify they are roughly doing what you want and then composing them to build up until you can plug it all together and now have a formula you can plug into the calculator to plug and chug all the rest of your data.

So in that sense yeah it does kind of replicate the magic of the first time you got a complex equation or BASIC program to run on your TI back in your school days.

feraloink6 hours ago

This is wonderful: APL is there! And a visual APL keyboard too.

ludsan5 hours ago

no uiua :(

evnu4 hours ago

Uiua is the first one that made array languages "click" for me due to the formatter.

etatoby5 hours ago

Came here to say the same thing. Uiua is my favorite language by far. BQN is also a cool "Nu-APL" but Uiua is just a full generation ahead.

srean5 hours ago

It's missing Nial I think.

JoshGG5 hours ago

MATLAB is an array language.

ljosifov20 minutes ago

Yeah - IDK why it never makes it to these lists. R too. Matlab being 2D matrix first/default gets it right for me there. IK matrices trivially translate to arrays, still: find 2D to be extra expressive on human level, for zero price paid. I get it it's all the same to the cpu. 2D rows-columns rectangle of data being the simplest data structure both necessary and sufficient covering a 1) matrix 2) spreadsheet 3) SQL table 4) directed graph of nodes and edges. (in the past I've read someplace that lists are for pie eaters, but wouldn't know myself

radiator5 hours ago

it is one of their cousins

nathell5 hours ago

Is this written by Arthur Whitney himself?

rana7625 hours ago

[dead]

rana7625 hours ago

[flagged]

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