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Fmbalbuena

00:30

@Adám hi, but i only have a cmc, CMC: remove the duplicates of character like "31415" => "3145"

Adám

∪

Fmbalbuena

⋄∪'31415926535897932384626338327950'

@Adám TryAPL bot down?

TryAPL

@Fmbalbuena bot error (not TryAPL or your code's issue) running this code; if this persists, please contact a developer

Fmbalbuena

what happened to @TryAPL?

@TryAPL are you ok? what happened?

Adám

⎕←'OK'

TryAPL

00:33

@Adám OK

Adám

I rebooted the server.

Fmbalbuena

What happened?

⋄∪'31415926535897932384626338327950'

TryAPL

@Fmbalbuena 3145926870

Fmbalbuena

@Adám Does APL support yield?

Adám

What is "Yield"?

Fmbalbuena

00:34

example (pseudocode)

def X without args
 loop
  yield 1
for I in call X
 output I

@Adám ^ prints 1 infinitely

like return but list

11Kilobytes

so streams/lazy evaluation. no methinks.

Fmbalbuena

or better, call X returns [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1...]

Adám

Not Dyalog APL. KAP maybe.

Fmbalbuena

KAP?

Adám

apl.wiki/KAP

Fmbalbuena

00:39

or @Adám APL supports infinite list?

Adám

Not Dyalog APL. KAP maybe.

Fmbalbuena

or @Adám APL supports infinite string?

Adám

APL doesn't support any strings at all, infinite or not.

Fmbalbuena

wait, WHAT?

'abc' is valid string in APL

Adám

It is valid APL, but not a string. It is a list of characters.

APLers tend to call it a character vector.

Fmbalbuena

00:42

⋄'a' 'b' 'c'≡'abc'

TryAPL

@Fmbalbuena 1

Fmbalbuena

@TryAPL why?

Adám

Because APL has no strings, only character lists!

Fmbalbuena

⋄'a' 'b' 'c'

TryAPL

@Fmbalbuena abc

Fmbalbuena

00:43

the output seems the same but what if

⋄'a' 'b' 'c' 2 'a' 'b' 1 'a' 0

TryAPL

@Fmbalbuena abc 2 ab 1 a 0

Adám

This is a list of a mixture of characters and numbers.

What you've discovered is that APL arrays need not be homogeneous.

Fmbalbuena

@Adám CMC: quine without ⌽

Adám

I'm not good at quines.

Fmbalbuena

@Adám Is APL TC with only 32-128 and "←⍵⎕" only?

Adám

00:50

I don't know.

Actually, I think it might just be.

You'd have logical AND ^ and NOT ~ which means you can construct any logic gate.

You can write a tail-recursive function using the function name.

You have comparisons < = > which can be combined with ~.

You can scan and reduce, replicate and expand, concatenate, index, and change values at specific indices or by condition with @

Flow control can be done with :

It should be possible to implement Rule 110.

Adám

01:29

@Fmbalbuena Yes:

 result←steps Rule110 now;i;step;next;pad
 result←0/[1]⎕FMT steps 1 steps/' '
 :For step :In +\steps/1
     pad←(steps-step-1)/0
     result,[1]←pad,now,pad
     next←0/0
     now←0,now,0
     :For i :In +\now=now
         :Select (0,now,0)[i+0 1 2]
         :CaseList (1 1 1)(1 0 0)(0 0 0)
             next,←0
         :Else
             next,←1
         :EndSelect
     :EndFor
     now←next
 :EndFor
 result,[1]←now

2 hours later…

Razetime

02:59

Does anyone know which method of Fast Fourier Transform is used in aplcart?

2 hours later…

Razetime

04:41

Anyone got APL solutions to day 23

6 hours later…

Adám

10:11

@Razetime It is from code.jsoftware.com/wiki/Essays/FFT by way of dfns.dyalog.com/n_xtimes.htm

Razetime

10:39

thanks!i

PyGamer0

@Adám what exactly does Indices of all items of array of shape Jv mean?

entry is ⍳Jv

Adám

@PyGamer0 Let's say you have a matrix of 2 rows and 3 columns. All the valid indices into that array are ⎕←⍳2 3

TryAPL

@Adám
┌───┬───┬───┐
│1 1│1 2│1 3│
├───┼───┼───┤
│2 1│2 2│2 3│
└───┴───┴───┘

PyGamer0

⎕←(2 3⍴⍳6)[⍳2 3]

TryAPL

@PyGamer0
1 2 3
4 5 6

PyGamer0

10:41

ah i see

@Adám example usage of this functionality?

Adám

A: Dijkstra's Challenge

APL, 13 12 bytes 1 byte thanks to @jimmy23013. 1-indexed. The array is stored in the variable m. +/,m×m=+/¨⍳⍴m +/∊m∩¨+/¨⍳⍴m Try it online! Based on the answer in J, which is a language based on APL. In TryAPL, to key in: +/m`em`c`1+/`1`i`rm With the array: +/m`em`c`1+/`1`i`rm `[ 2 4 `r 3 `

Adám

11:06

@Oberon Hi there, and welcome to the APL Orchard!

Oberon

Hello!

Adám

You have quite some experience with APL, I can tell.

PyGamer0

11:33

@Adám is the dyalog logo based on ⊃∨∧⌊○⊂?

Adám

That's my assumption, but I don't actually know. I can ask the CEO…

PyGamer0

⋄⊃∨∧⌊○⊂

TryAPL

@PyGamer0
┌─┴─┐
⊃ ┌─┼───┐
  ∨ ∧ ┌─┼─┐
      ⌊ ○ ⊂

PyGamer0

⋄ 2(⊃∨∧⌊○⊂)2

TryAPL

@PyGamer0 Response looks like a 1-by-0 matrix.

Adám

11:40

Maybe I'll use ⍬(⊃∨∧⌊○⊂)⍬ next time I need ⍬

1 hour later…

Kamila Szewczyk

13:08

min←((⊢~⌈/)⊢)⍣(2=∘≢⊢) can this "joke" minimum function be golfed in some way?

Master Quiz

@KamilaSzewczyk ((⊢~⌈/)⊢) is just (⊢~⌈/)

Kamila Szewczyk

it's not. valence matters :)

or does it?

when i tested it, it gave weird results as a dyadic fork.

i presume ⍺⍺ ⍣ ⍵⍵ calls ⍺⍺ monadically and ⍵⍵ dyadically

Master Quiz

I get something strange when I try to change the left piece. Why (2=≢) [or (2∘=≢)] doesn't work?

Kamila Szewczyk

because the right operand is called dyadically

not monadically

Master Quiz

@KamilaSzewczyk Dyadically between what?

Kamila Szewczyk

13:22

previous and current application result, i presume.

help.dyalog.com/15.0/Content/Language/Primitive%20Operators/…

Master Quiz

@KamilaSzewczyk Oh yes, for example when you do ⍣≡

2 hours later…

11Kilobytes

15:29

How do you get newlines for debugging?

11Kilobytes

16:05

⎕UCS 10 is the unicode newline character.

Fmbalbuena

16:17

@Adám Try it online!

6 hours later…

Master Quiz

22:25

@Adám I still have this error...

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