The Nineteenth Byte

@lyxal Do you think it would be better if my Kirkman triples problem (in sandbox) would be better if q could be any 6t+1 prime power? (The construction still works in that case)

I restricted further to prime number because I was worried some languages would not be well-suited to general finite-field arithmetic

lyxal

I'd have to check the challenge

Parcly Taxel

codegolf.meta.stackexchange.com/a/25037/110698 here

lyxal

@ParclyTaxel if you think that makes the challenge more accessible to programming languages, then sure

New Posts

4:47 AM

1

Q: Generate a Kirkman triple system

Given a universe of \$v\$ elements, a Kirkman triple system is a set of \$(v-1)/2\$ classes each having \$v/3\$ blocks each having three elements, so that every pair of elements appears in exactly one block all classes are partitions of the universe. Kirkman's schoolgirl problem corresponds to ...

code-golf math number-theory combinatorics

PyGamer0

7:05 AM

@NoHaxJustRadvylf lol

mousetail

@NoHaxJustRadvylf Yet everyone hates DBMS that don't do this even more

graffe

Morning!

lyxal

o/

graffe

7:22 AM

How are things?

Heatwave?

@lyxal out of interest, can you understand codegolf.stackexchange.com/a/251036/108721 ?

lyxal

Definitely not.

Too smooth braib

*brain

graffe

I don't even understand the one line comment it refers to

I hope to get there though

Is having a smooth brain bad?

Sandbox Posts

7:43 AM

0

A: Sandbox for Proposed Challenges

chess smallest amount of steps If you place a horse on any square of the board what is the smallest amount of steps to reach a certain position? Rules It is an 8*8 board. You start at the top left corner. The same moves are possible of a regular chess game. example For example this is the desir...

lyxal

@graffe urbandictionary.com/define.php?term=Smooth+Brain

graffe

@lyxal thanks! Being smooth is normally good :)

mousetail

@SandboxPosts Is he gonna just repost if every time?

lyxal

8:20 AM

Probably lol

New Posts

11:25 AM

0

Q: chess smallest amount of steps

If you place a horse on any square of the board what is the smallest amount of steps to reach a certain position? Rules It is an 8*8 board. You start at the top left corner. The same moves are possible of a regular chess game. example For example this is the desired output with a queen: (0 is ...

code-golf chess

mousetail

12:08 PM

@NewPosts He actually posted it

TKirishima

3:18 PM

Is there any way to see which languages are most used on average to solve a problem across all CGSE responses?

NoHaxJustRadvylf

@TKirishima Yes: gist.github.com/Radvylf/…

There are some issues with languages being missing/incorrectly tree-ified in that list, so don't trust it 100%, but it should still be pretty accurate

TKirishima

@NoHaxJustRadvylf Thanks a lot ! :D

@NoHaxJustRadvylf Thats ok! Thanks for the info

user

3:33 PM

@NoHaxJustRadvylf What do the last two columns mean there?

NoHaxJustRadvylf

Golfiness rating and usage-adjusted rating

user

Wow, that means I dragged Scala's rating down to worse than Regex and Scratch

TKirishima

XDDDDDDDDDD

Vyxal is before SQL, Brainfuck,K, Kotlin, Rust, Prolog and many more. Thats impressive

user

Vyxal's a dedicated golflang, of course it's better than all of them

K is extremely concise but it's still not a golflang

NoHaxJustRadvylf

Fun fact: the ratio between any two languages' rankings is the expected difference in size between answers in those languages

So a 600 rated language will on average have twice as long of answers as a 1200 rated one

user

3:41 PM

Oh wow

NoHaxJustRadvylf

And a 1000 rated language is average, making anything which can achieve 2000 twice as concise as the average language

GingerBot

4:01 PM

Hello new user and welcome to TNB!

PyGamer0

4:15 PM

@NoHaxJustRadvylf is jelly fork caird's jelly ?

NoHaxJustRadvylf

Yeah

PyGamer0

damn thats better than vyxal

NoHaxJustRadvylf

Keep in mind it'll only have been used on challenges where it's advantageous over normal Jelly, so like the Vyxal flag variants it's hard to score fairly

PyGamer0

ok

i hope flax will be around jelly in that list

GingerBot

translating a bunch of C code from xfce4-notifyd into python

I love open source, makes it so much easier to ~~steal~~ borrow other people's work and be lazy!

TKirishima

4:21 PM

Is GingerBot a real bot ?

GingerBot

No, I'm @Ginger

using this account because I currently can't use my main for reasons

TKirishima

Oh ok

GingerBot

This account, however, is also a bot which does stuff in the katlani room

so if you interact with it in there it's automated

...or maybe I am a bot, and I've gained sentience and am planning to rule/destroy/consume the world!

NoHaxJustRadvylf

Have you still not gained access to your main account?

GingerBot

Not yet, soon.

I'm not happy about it either

NoHaxJustRadvylf

4:29 PM

@GingerBot Who was the new user?

GingerBot

@TKirishima

I assume they're new because I haven't seen them before

NoHaxJustRadvylf

They've been in chat before

GingerBot

darn it

TKirishima

Im not new

GingerBot

before I got here I guess

TKirishima

4:30 PM

I just dont come often

GingerBot

sorry, welcome back in that case!

TKirishima

Ive been here for ? 3 months ig

NoHaxJustRadvylf

Really, welcoming new users to chat isn't recommended in the first place, but if you do, it's important to make sure they're actually new :p

One way you can do that is by looking at the room's unique user count to see when it increments

E.g., it's 1328 right now

GingerBot

blyat

just trying to be nice

NoHaxJustRadvylf

And if they have posted here before, it'll show "last post here ... ago" in the room info

GingerBot

4:33 PM

got it, thanks

NoHaxJustRadvylf

@GingerBot Yeah, I get it. But it could probably come off the wrong way if it's like, someone who's been on the site for five years :p

GingerBot

(which is a mistake I think I have made :b)

NoHaxJustRadvylf

5:35 PM

CMQ: Should a command line tool error if given too many arguments?

m90

5:58 PM

@NoHaxJustRadvylf I think so.

mousetail

7:29 PM

First draft of controller script for the radiation hardening koth, any initial feedback? codeberg.org/Mousetail/Radiation-Hardened-Koth

Still need a way to export the results

TKirishima

What is codeberg ?

Like it seems like a git plaform but what is the difference with Github, GitLab or BitBucket, but why codeberg ?

emanresu A

Personal preference, probably

Github's evil and gitlab's a sussy baka

idk about bitbucket

graffe

7:50 PM

In python lru_cache and cache work by caching results of a function with exactly the same arguments. But I have a function that compares two values of a large matrix. The matrix doesn't change but should I really add it as an argument to the function so lru_cache can do its magic

eg foo(i, j, large_matrix) where only i and j ever change

pxeger

It surely won't make a difference

graffe

What does lru_cache do with large_matrix? Is it just looking at the value of the reference?

pxeger

It stores them in a dictionary I think

graffe

Rather than caching the whole matrix

pxeger

so if the matrix is not hashable I'd expect an error

graffe

7:54 PM

Right that's my problem. I could define it as a global variable but wondered if there was another route

pxeger

A closure?

graffe

@pxeger oh go on....

I am never confident enough to use closures unless someone tells me how

pxeger

def outer(large_matrix):
    @lru_cache
    def inner(i, j): ...
    return inner
f = outer([...])

then use f(i, j) etc

graffe

That's all interesting idea, thank you

Do you mean return inner?

pxeger

Yes

graffe

7:57 PM

Should .... be filled in with something?

pxeger

Yes

graffe

As in outer([...])

pxeger

that's the value of the matrix

graffe

Ok

pxeger

whatever your matrix is

but if the matrix never changes, you should only call outer once

graffe

7:58 PM

Then how does f(i, j) work?

It looks like f takes a matrix not two numbers

Oh I see

pxeger

f is the result of outer, i.e. inner

graffe

I have learned something! Thank you

So the code for inner can use large_matrix ?

pxeger

Yes

graffe

This is a great solution

From a python guru

Thank you

tybocopperkettle

8:53 PM

What's a really common constant in golfing languages? I'm planning/kind-of starting to make a language at the moment and it only has a 128 char codepage so I was thinking of presetting the register to a constant that's commonly used (maybe this has been done before but idk). That way programs that don't need the register for other things can get this constant in one byte.

GingerBot

how's about zero

and if you have two maybe make the other one

tybocopperkettle

@GingerBot Have the register at 0 at the beginning?

GingerBot

yes

tybocopperkettle

@GingerBot There's only one

GingerBot

ah

wait, I don't recognize you

are you new here?

tybocopperkettle

8:56 PM

Sort-of

GingerBot

???

tybocopperkettle

I'm a friend of emanresuA's

emanresu A

yes

GingerBot

Well, nice to meet you friend of emanresuA's

tybocopperkettle

@GingerBot I've probably been here for a couple of months

Or less

GingerBot

8:57 PM

welcome (back)+ to TNB!

tybocopperkettle

Thank you!

NoHaxJustRadvylf

@tybocopperkettle I'd go with an empty list

That might make certain recursive algorithms shorter

GingerBot

!emoclew er'uoY

or maybe use flags to set what it is?

tybocopperkettle

@NoHaxJustRadvylf Perhaps

@GingerBot I don't think I'll have flags

GingerBot

o

h

NoHaxJustRadvylf

8:59 PM

You say that like it's a bad thing, Ginger :p

tybocopperkettle

I could, I just feel like they're a bit cheaty sometimes

mousetail

@emanresuA Gitlab was great for years but now they deleting old repos and restricting CI minutes to a unreasonable degree so it's not really worth using anymore

GingerBot

well I'm all for cheaty so

NoHaxJustRadvylf

Language design is way more fun when you can't just make any hard decisions into flags

GingerBot

well yes but that sounds hard and I can't be bothered most of the time

tybocopperkettle

9:00 PM

@GingerBot Lol

@NoHaxJustRadvylf What's an example?

GingerBot

I am not a very good programmer so I would rather make something into a flag and be done with it then spend 5 hours trying to fit it into the language nicely

NoHaxJustRadvylf

@tybocopperkettle I misread register as something else, so ignore the word recursive. But whenever you do need the register (assuming it's like Jelly's), it's usually because you're iterating over a list and doing multiple things at once, and typically at least one result you'll want is also list, so initializing the register to an empty list makes it easy to just push to the register each iteration.

tybocopperkettle

True

NoHaxJustRadvylf

I like the idea of using the register as another 1-byte constant though, if you've got a good selection of array quicks/transformers/whatevers, using it for something like 16 or 100 or an infinite list of natural numbers could be cool

tybocopperkettle

Yeah, how about the alphabet?

NoHaxJustRadvylf

9:05 PM

Good idea

Even better since challenges involving the alphabet probably don't need much complex iteration over arrays, so it's really unlikely you'd need the register for register-y stuff too

GingerBot

ooh good point

tybocopperkettle

^

I just had a look at Vyxal and (if I write my program correctly) the most common constant (that would be more than one byte otherwise) is ₆ (64)

NoHaxJustRadvylf

Interesting. At least in JS, the most common number constants are, ignoring digits 0-9: -1, 10, 20, -2, and 11

64 doesn't show up for a while, coming after numbers like 16, 12, 100, 60, 99, 26, and even 65

I guess golfing languages have more efficient ways of getting those numbers than praclangs do, though

(source for that list: gist.github.com/Radvylf/1bebd9050ee2d530007bf67d2f325843)

Unrelated String

65 makes sense because it's the codepoint of A

emanresu A

ah lol

GingerBot

9:13 PM

I can understand -1 for fixing OBOEs and stuff

Unrelated String

-1 is pretty useful in general, and that's even assuming this corpus did manage to filter out cases of subtracting 1

GingerBot

and that, of course

NoHaxJustRadvylf

@GingerBot JS doesn't even have repeat-by-negative-one for reversing, so it's more useful than just that

GingerBot

had a brain faliure

NoHaxJustRadvylf

@GingerBot I've never seen off-by-one abbreviated before and now I know why

Just wait 'til I start programming in JS's evil twin and accidentally make a BASOON

4

GingerBot

9:16 PM

*oboe noises*

~~you sent that knowing I would star it~~

NoHaxJustRadvylf

BigInt Addition: Size Overflows [object Number]

AviFS

@NoHaxJustRadvylf hiiiiiiiii

GingerBot

@AviFS iiiiiiiiih

emanresu A

joking lol

wait no dammit

NoHaxJustRadvylf

→ 5 messages moved to Off-Topic TNB

GingerBot

9:29 PM

oh also for some reason IDLE's keyboard shortcuts are case-sensitive

AviFS

@GingerBot hihihi heeheeheehee

NoHaxJustRadvylf

@emanresuA You're not JoKing, you're emanresu A!

3

AviFS

@NoHaxJustRadvylf uh oh, i feel jail coming

GingerBot

if I have capslock on Ctrl-S doesn't work

AviFS

@NoHaxJustRadvylf starred

Zion mycelia adamancy

9:30 PM

@AviFS Hey Avi, been a while! :P

AviFS

@Zionmyceliaadamancy Hey caird! How have you been?!

GingerBot

@AviFS I don't think that's interesting enough to warrant a star, that joke gets made a lot :b

Zion mycelia adamancy

@AviFS Been alright, chilling on summer vacation. Yourself?

GingerBot

I hate it when I send a message but it sounds super aggressive so I have to go back and add a :b

Zion mycelia adamancy

That's why I always end with :P

GingerBot

9:31 PM

I must not harm humans or through inaction allow humans to come to harm

AviFS

@GingerBot probably not, i'm pretty easy to please, i don't know if you've noticed :p

GingerBot

fair enough lol

AviFS

also, i never know what jokes are like totally old by now haha

GingerBot

also: this is ginger using GB's account for reasons

NoHaxJustRadvylf

→ 153 messages moved to Off-Topic TNB

AviFS

9:32 PM

i feel like this happens a lot that i crack up at something totally overused by the time i'm around haha

@GingerBot i approve

Wheat Wizard

9:55 PM

I've been unable to work on hgl for a couple months due to my computer not being good enough to run it.

GingerBot

holy garbled lemons?

Wheat Wizard

Haskell golfing library.

Coming back I am a little bewildered. The documentation is thorough but it uses phrases like "Cokleisli category". I must have been significantly smarter a couple months back.

7

GingerBot

I'm pretty sure all coders feel stupid when looking at their old work

Wheat Wizard

Usually I feel that past me was stupid.

GingerBot

...or that

Wheat Wizard

10:00 PM

Cokleisli categories are kind of cool actually. I can't believe I forgot about all this.

GingerBot

what are they?

NoHaxJustRadvylf

If it has "category" in the name it'll probably be something "cool" in a very esoteric way :p

Wheat Wizard

They are sort of like functions that have a narrower output than their input.

Well really a category is all about composition, so it's a special sort of composition for things that get narrower.

GingerBot

as in they output less? confused

Wheat Wizard

So a function of the type [a] -> a is narrower.

GingerBot

10:04 PM

what do you mean by "narrower" tho

Wheat Wizard

So it has to do with the composition.

GingerBot

Tell me more, Smart Cat

Wheat Wizard

Normal functions compose when the input to one is the same as the output of another.

GingerBot

okay

Wheat Wizard

(a -> b) -> (b -> c) -> (a -> c)

Unrelated String

10:05 PM

i feel like i read something about comonads at some point; i assume these are related? considering the relationship between normal monads and kleisli arrows

Wheat Wizard

Yes they are very related.

You can't compose say ([a] -> b) and ([b] -> c) because [b] is not the same as b.

GingerBot

Is b a list?

Wheat Wizard

b is just some type.

We don't know what.

GingerBot

why is it in brackets

Wheat Wizard

The brackets mean "list of" so [b] is a list of bs

GingerBot

10:07 PM

oh

Wheat Wizard

But b is just a b

Cokleisli composition is a composition like this where each of the arrows is sort of narrowing. It has the general type (m a -> b) -> (m b -> c) -> (m a -> c)

Zion mycelia adamancy

@WheatWizard It's category theory, it only ever makes sense in the moment :P

Wheat Wizard

If it makes sense at all.

GingerBot

It doesn't make sense

user

@WheatWizard Can't you just call do g . pure . f there though?

GingerBot

10:09 PM

Sadly, I am but a stick of butter and cannot understand advanced theoretical mathematics.

Unrelated String

you can't compose them directly

NoHaxJustRadvylf

A coconut is just a nut

user

Oh ok (to Unrelated, not to coconuts)

Zion mycelia adamancy

Category theory makes sense, so long as you don't think about it

8

Wheat Wizard

@user Sure, but that's a different operation than regular composition.

List is a bit of a confusing example since it's not a comonad.

Tuples are a better example.

Zion mycelia adamancy

10:10 PM

Tbf, composition is only uniquely defined for a chain of single argument functions

user

Ah okay, so like a -> b and (b, c) -> d?

Zion mycelia adamancy

As soon as you introduce a function that takes 2 or more arguments, you have to specify how the function transforms those arguments

user

Well, currying lets you treat those as single arg functions, right?

GingerBot

I dream of the day when something that falls within one of my very narrow sets of expertise comes up in this room so I can speak of it in more than vague, noncommittal terms

Wheat Wizard

the cokleisli comp for tuples would be ((x, a) -> b) -> ((x, b)-> c) -> ((x, a) -> c)

user

10:12 PM

Or treating the arguments as one single argument wrapped in a tuple

Zion mycelia adamancy

@user Assuming you define them as curried functions, sure

Wheat Wizard

You reuse the x value for both functions.

Unrelated String

oooh

user

Any good books on category theory?

Zion mycelia adamancy

@GingerBot What;s the difference between "crimson", "ginger" and "orange"?

Unrelated String

10:13 PM

i can really see how that would come up in a golfing library now

user

Their MD5 hashes are all different

GingerBot

Crimson is a color, Ginger is me, and Orange is a fruit

and baba is you

Zion mycelia adamancy

@UnrelatedString Pretty sure Dennis intended for this to be a quick before he left

user

Jelly has monads and monads? :P

7

Wheat Wizard

@user The Bartosz book, is pretty nice. It's fun, not too hard or anything.

GingerBot

10:14 PM

got crimson and cinnamon mixed up where did I put my braincells

Zion mycelia adamancy

@user It also has monads, and the occasional monad

user

@WheatWizard Ooh, it's even written for programmers, thanks for the rec

GingerBot

but "monad" == "monad"

Unrelated String

@Zionmyceliaadamancy like L xyƈ R = L x R y R? yeah i've found myself needing that quite a bit lmao

user

@Zionmyceliaadamancy You mean it also has monads and the occasional monad?

GingerBot

10:16 PM

really most of the software I know about is not software you use in code golf

user

@GingerBot Java: new String("monad") != new String("monad")

GingerBot

now if we were talking about writing Gtk applications in Python I would have a lot more to say

emanresu A

@user Same with JS

Wheat Wizard

polytope.miraheze.org/wiki/Point

Unrelated String

jelly doesn't have the monad, jelly programmers just have to channel its powers to maintain sanity

GingerBot

10:17 PM

where does dbus come up in code golf?

Zion mycelia adamancy

in Jelly, Jun 17, 2016 at 16:29, by Dennis

The next quick I implement with definitely be x mdQ y -> m(x) d m(y). Can't count the times I've needed that.

Unrelated String

xd

GingerBot

and then he was never seen again

Zion mycelia adamancy

D:

emanresu A

Javascript's strings are okay, its Strings are not.

Unrelated String

10:17 PM

also i think that would be over wouldn't it

Zion mycelia adamancy

Kinda, yeah

GingerBot

you could say the same about Arduino

user

Okay, I think I get kleislis, they just sorta unwrap stuff to compose it, now for cokleislis

Zion mycelia adamancy

Over would be x dmQ y, given the traditional order

GingerBot

@user I mentally pronounce that "cockle-islis"

Wheat Wizard

10:18 PM

Kleisli arrows are super useful.

They are like functions that also produce extra stuff.

Unrelated String

i guess the reversed order would be for easier use with chain separators

this is why i'm making my operators infix :P

Zion mycelia adamancy

I only noticed that message from Dennis after I finished my fork :/

Unrelated String

f

Zion mycelia adamancy

Jam will be different

Might even try to implement an Under quick

user

@WheatWizard Do they do more than flatmap/bind?

Wheat Wizard

10:21 PM

@user Nope, bind and kleisli comp can be defined in terms of each other. They are two sides of the same coin.

That coin being monads.

user

Oh ok

Unrelated String

join me
do under without even defining standalone inverses

Wheat Wizard

IMO kleisli composition is the more intuitive way to think about monads.

Zion mycelia adamancy

@UnrelatedString No

Unrelated String

:(

Zion mycelia adamancy

10:22 PM

If I implement an under quick, I will add an inverse attribute to every atom

Wheat Wizard

The problem with making a Haskell golfing library is that I start with trying to implement something practical and useful and instead I get distracted by some cool category thing for like 3 days.

Zion mycelia adamancy

Even non-injective atoms, get fucked "functions"

@WheatWizard Do what I do: don't know shit about category theory. Super easy :P

Wheat Wizard

It's Haskell you learn category theory by osmosis.

GingerBot

so you're telling me if I come over to your house and just kinda stand next to you for two days I will then understand category theory? sign me up

emanresu A

10:37 PM

CMC: Difference of two unit fractions

AviFS

@WheatWizard It's TNB-- I'm gaining IQ points by osmosis.

@user Seven Sketches

Also, Awodey is good.

And Emily Riehl is supposed to be good, but it hasn't been for me.

Also, try out the Catsters, of course. And remember pirating on libgen, which hopefully won't get me shadowbanned. Probably not good to have that as a searchable message on my online persona, but oh well.

@emanresuA The first one minus the second one.

AviFS

11:02 PM

@emanresuA In Dyalog APL, you can do -⍥÷ where monadic ÷ means the inverse. So 2 -⍥÷ 4 is .25 That's 1/2 - 1/4, assuming that's what you meant. I'm not sure the best way to actually make that into a stand alone train, though. For a defn, I think the shortest would be: {-/÷⍵}.

user

@AviFS Thanks!

AviFS

@user Of course, I really highly recommend Seven Sketches. I lead an online reading group with that for a while. We worked up through Chapter 4, I think. I'd love to do that again, sometime. A CGCC group would be fun. But of course, for Seven Sketches, and all those other books, you really have to work through it, and the problems.

If you find a breezier reading that helps you get at least a taste for category theory a bit more leisurely, that'd be awesome. Let me know!

@user On breezy reading, There's How to Bake π, by Eugenia Cheng of Catsters, a category theorist. But that didn't satisfy my category theory craving. It's a unique math book, though. Maybe written for people not already as mathematically inclined.

emanresu A

@AviFS That one's good :P

AviFS

Also, Graphical Linear Algebra is unique math reading in that it's quite leisurely and very new and "aha" without actually having to work through problems to get it. graphicallinearalgebra.net

There are some category theoretic, or at least category adjacent, ideas in there. I highly recommend that if you want math nighttime reading, which is hard to find. It's a lot of fun, just period.

Actually, it's very category theoretic. And it's maybe not all quite so easy, haha. But still chiller reading than most. Highly recommend.

@emanresuA Oh you know it? What'd you think?

I got it for my birthday many, many years ago, and only more recently gave it a shot.

@user Okay, one more thing. I spent some time on this once upon a time.

Since you responded to the Youtube thing, there's one other relevant Youtube thing. Bartosz Milewski, category theorist and Haskeller, has a book called Category Theory for Programmers, free online. Additionally, he taught it as a course, and there's a playlist on YouTube of him teaching it.

Category Theory for Programmers Course, delivered by the author, YouTube Playlist

Category Theory for Programmers book, published online free by author But you can also download a very nicely typeset pdf from libgen, not clear if that's also approved by the author or not.

And finally, for that particular book, Code Report (Conor Hoekstra) has video playlist for each chapter of the book.

He's the guy who runs the Programming Language meetup group, based, I think, in Toronto, but also doing events in NY sometimes. And usually the events are online. And he's also been quite relevant in APL circles recently. For instance, he's doing the APL meetup in NY advertised in the APL Orchard, he's doing the Array Cast podcast, and he has lots of APL videos (Haskell and other langs, too) on his channel. Anyway, Hoekstra also has an accompanying YouTube playlist, if you like that book.

Accompaniment to Category Theory for Programmers book, YouTube playlist by code_report

Those are some of the best resources for category theory for amateurs I found while I was into that!

@AviFS Out of all of it, I highly recommend Graphical Linear Algebra for anyone looking for fun math reading. And Seven Sketches for anyone wanting to work through category theory.

4

(And actually, the authors of Seven Sketches have lectures online for that book, too. They teach a course with it. Although, the lectures didn't feel super thorough. More of a compliment to the book.)

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