The Nineteenth Byte

lyxal

12:01 AM

Well most built-ins in a golflang only need to return 1 thing

Meaning the only time you're getting benefit from multiple return is with user defined functions

And when you're using those, typically you're using them in contexts where 1 return value is used

So I don't see how not having it is losing power

noodle man

12:18 AM

maybe it’s not as useful in a golflang

@lyxal if you call a filter or something it could be useful to return two different booleans to make two lists each which was filtered by something slightly different, for example

lyxal

why wouldn't you just dup filter1 swap filter2?

noodle man

ofc but it could be shorter if they share logic

also on filter1 filter2 would be shorter

does vyxal have on?

Unrelated String

divmod is one possible case for multiple returns

noodle man

yeah neil suggested it above

lyxal

I'd argue divmod should be a list

[div, mod]

Unrelated String

12:25 AM

and doesn't 05ab1e get some mileage out of its uninterleave sometimes

lyxal

that's just standard uninterleave

noodle man

uninterleave should certainly give two separate lists

Unrelated String

think there's also some stack language that has a single byte for dup reverse

noodle man

that seems kinda useless tbh

lyxal

@UnrelatedString bifuricate?

Unrelated String

12:26 AM

there is a reason i didn't mention remembering seeing it do anything :P

noodle man

you could do palindromise halve in vyxal right?

does halve give two lists or 1

lyxal

@noodleman it has its benefits

like, for example, i do X to your source code, you do X to the output challenges

very helpful for those

Ḃ in Vyxal

stole it from 05ab1e

which uses Â

@UnrelatedString 38 uses on the site in Vyxal 2 as of Jan 2023

which is more than something like discard (_) and join on (j)

Unrelated String

wow

lyxal

github.com/Vyxal/Vyxal/issues/14

@noodleman so would parallel-apply: filter1 filter2

@noodleman also, in the bytes you've used for applying two different conditions, you could have just used two separate filters

noodle man

oh yeah

perhaps i’m not in the best position to speak on stack golfing languages considering i’ve only used vyxal and golfscript and my vyxal knowledge is limited : -

lyxal

12:37 AM

tbh I think the power loss you're thinking of in most stack golflangs is a lack of a modifier system

which is something I think is a valid observation

modifiers + a function as stack values system does better than direct application functions

noodle man

~~(well i also used thunno but we don’t talk about it)~~

lyxal

lol

noodle man

i don’t necessarily agree that vyxal really benefits from having first-class functions

modifiers definitely though

lyxal

@noodleman means you can have built-ins that act as soft modifiers

while still giving normal built-in functionality

noodle man

well i’m thinking of how uiua deals with it

which is to effectively have first class functions except that they don’t exist in the stack

lyxal

12:42 AM

@noodleman I'm talking in terms of codepage utilisation and golfiness

noodle man

i have personally never used a function object in vyxal

soft modifiers? like, only if top of stack is a function then modify it, else do something else?

lyxal

@noodleman things that would otherwise (or should) be a modifier but codepage space restrictions make that not possible

noodle man

ok yeah

lyxal

ȯ for example

first n numbers where a condition is truthy

for example, that's a modifier (quick) in jelly

but in vyxal it's an element

and it takes a function object

noodle man

yeah i get it

lyxal

12:45 AM

I know you do but for the sake of other people :p

noodle man

japt does it like that also

although japt first class functions are a whole mess

you can’t define a function and call it later, you can only do operations like run until true, run on first N integers, etx

lyxal

also, first class functions make things like custom modifier definitions easier in vyxal 3

noodle man

oh custom modifiers? cool

yeah it that would make parsing easier

lyxal

github.com/Vyxal/Vyxal/blob/version-3/documentation/…

custom elements and modifiers

noodle man

my phone keeps autocorrecting “ig” to “it” and “if”

Unrelated String

12:50 AM

:(

lyxal

different topic, but boy i sure love the hyper sensitive scroll speed of visio

because I find myself once again using visio

to document the control flow of the Java BigInteger compareTo method

and boy did the BigInteger implementors love ternaries

noodle man

@lyxal ~~google drawings~~

lyxal

I have a visio subscription from the uni I'm gonna make the most of it gosh dang it

even if it means suffering through the $1000 program that's surprisingly less stable than word

and less intuitive than other sites like diagrams.net

noodle man

my brother has used google drawings to make actual art lol

granted, not particularly visually appealing art

lyxal

okay visio has slightly redeemed itself

you can add custom connection points to shapes

which makes things slightly better

noodle man

1:04 AM

excalidraw is also really cool for making diagrams but it's probably a different use-case than you have

lyxal

but does excalidraw ask the important questions?

in The Sand Trap, Mar 7, 2023 at 2:39, by lyxal

where are the shapes?

noodle man

2:19 AM

~~copilot probably knows~~

l4m2

Many tasks so if locked, go to handle a new task rather than wait, so that everything is in user mode. What is it named?

att

5:29 AM

@emanresuA is that for arbitrarily many primes

emanresu A

I was thinking of all primes but I'm not sure if that exists

Tbw

I've been thinking about it for a while now.

Definitely works for 3 primes, but there seems to be many possible structures, much less constricted than 2.

For all primes, if our solution is symmetric between the primes, it amounts to finding a certain coloring of Young's lattice, where for every node, it or one of its direct successors is colored

att

I think you can inductively build a structure

for +1 in a new dimension shift the solution in the lower dimensions by 1

hm, but it will go back to 1

Tbw

for 2,3,5 the simplest solution is 2^a*3^b*5^c * k where a = b = c mod 2

whereas the structure for the 2,3 case is a=b mod 3, and neither of these really work for 4 primes

emanresu A

For 2,3,5,7 I think 2^a*3^b*5^c*7^d where a+b+c+d mod 5 = 0 works? And that appears to generalise?

Tbw

5:43 AM

but then none of 2,4,6,10,or 14 are included

emanresu A

Ah, I see

l4m2

6:03 AM

2^a3^b5^c7^d,a+2b+3c+4d=0(mod 5) any fault?

Should be correct

and pattern go

@Tbw This maps [0,1]a+[1,0]b+[1,1]c=0(on F_2^2)

Tbw

@l4m2 yeah this works for any number of primes

l4m2

Now consider composites. 1-2-4 is possible(0/1/2), 1-2-3-4(0/1/3/2), 1-2-3-4-5-6(0/1/3/2/5/4)

att

oh that's cool

Tbw

1-2-3-4 is the same as 1-2-3

l4m2

@Tbw How?

Tbw

6:18 AM

any 1-2-3 sequence is a 1-2-3-4 sequence

att

can we generalize to 1,-1,2,-2,...?

Tbw

oh wait im wrong

there are no 1-2-3-4 sequences

Since any 1-2-3 sequence has n implies 6n = 3*2n, and 8n = 4*2n

l4m2

1-2-8 is impossible. If X is chosen, then X/8..8X(6 elements) can't

1-2-3-4 can be generated easily modified mine

Tbw

that only outputs 1s

att

@att appears so

l4m2

6:30 AM

@Tbw The 1s count for each n

Does ratio converge at 0.47252747?

Tbw

i'm still confused. what are the first terms of the sequence?

l4m2

@Tbw This outputs elements

Why does the fs.writeFileSync fail?

att

can't you console.error?

Tbw

@att ok now that we know it's possible, i'll post the challenge

att

hopefully that's not overlooking something

Tbw

6:43 AM

no i definitely works. as long as you map each prime and 1 to the elements of a group bijectively, (with 1 as identity) it works

att

ah of course

l4m2

Is the all primes version 1-2-3-5-7-.. impossible?

Tbw

att's solution solves the all prime problem

l4m2

What does it do?

att

filter a-b+2c-2d+3e-3f+...=0

Tbw

6:49 AM

for 2^a 3^b 5^c 7^e...

l4m2

See, modulo on F_2^inf

Tbw

Well this is actually on (Z,+). Any countably infinity group works

l4m2

F_inf^inf

att

so any bijection and any sum

New Posts

0

Q: Output a 1-2-3-5-7... sequence

Follow-up of my previous challenge, inspired by @emanresu A's question, and proven possible by @att (Mathematica solution linked) For the purposes of this challenge, a 1-2-3-5-7... sequence is an infinite sequence of increasing positive integers such that for any positive integer \$n\$, exactly o...

l4m2

7:02 AM

@Tbw Seems 1,2,3,4,... would fail, what's the other rule?

Tbw

That's not a group

has no negatives

l4m2

so -1,1,2,3,... is fine?

Tbw

Every element has to have an inverse, something that you can add to it to get 0, its negative

a group

l4m2

Do ±1,±3,±5,... work?

If no then there's only one choice

Seem no

att

no, 1+3 doesn't have a negative

Tbw

7:12 AM

@l4m2 no because you need 0, and even if you add 0, then it's still not closed under addition. There are still many ways to do it because there are many countably infinite groups and uncountably many bijections from the primes to each of those groups

Correction: it must be an abelian group

l4m2

Does Pxeger's solution extend here?(choose x, then remove x*p^k)

att

assign every number a value v(n) such that v(mn)=v(m)+v(n)
if v(n)=0 then it's in the set, if not then v(n p) is iff v(p)=-v(n)

also need v(prime)!=0

emanresu A

9:00 AM

@NewPosts Seems like the answer to #2 (natural density) is 0? I don't have a formal proof, but the proportion of elements under some N converges to 0 as N grows arbitrarily large

att

9:27 AM

I wonder where/if the greedy algorithm breaks

The Empty String Photographer

If the greedy algorithm becomes too fat, their stomach explodes. When that happens, it’s probably broken.

att

10:18 AM

i think the greedy algorithm might actually work

New Posts

11:00 AM

The Sand Trap is now unfrozen. Did the freeze make chat great again?

5

lyxal

room topic changed to The Nineteenth Byte: The Nineteenth Byte: General discussion for codegolf.stackexchange.com | Guidelines: cgcc-se.github.io/chatiquette | Use The Sand Trap (chat.stackexchange.com/transcript/136286/the-sand-trap) for off-topic discussion (no tags)

I must say, this last week of chat has been some of the best fun I've had here in a long time

zoomlogo

11:36 AM

@lyxal will you answer your own meta post?

lyxal

eventually

lyxal

12:48 PM

I might let a few other people answer first

l4m2

Forgot to turn off ratio computer of 272546, it's now 0.4725274725

New Posts

1:19 PM

0

Q: Print all legal chess moves

The game of chess has moves. Lots of moves. But how many, exactly? In this challenge, you must print all possible chess moves for a single player (black or white — you choose). Moves are distinguished by the piece, the starting square and the ending square. Also, if the move is a promotion, moves...

code-golf chess

Ginger

3:58 PM

I finally have it

Neil

4:20 PM

@NewPosts bah, @Arnauld FGITW'd me by 58 seconds

math scat

@NewPosts I couldn't be active enough in TNB the past weeks to post a separate answer, but I do feel like the chat was better than before

Simd

5:24 PM

If I have a to the power x, then x is the exponent but what is a called?

math scat

5:40 PM

the base?

The Empty String Photographer

@mathscat yes

it is called the base

But that was already answered in the Math.SE chat

Unrelated String

11:06 PM

CMC: given a printable ASCII character, output another printable ASCII character such that the XOR of their codepoints is a third printable ASCII character

i/o can of course be with the codepoints themselves

i was so close to sandboxing this to post on main, until i stuck with it for another two minutes and found a solution that's juuuuust a bit too simple :P

(inspired by codegolf.stackexchange.com/questions/207178/xor-two-strings)

Neil

@UnrelatedString x=>x<96?96:32

Unrelated String

...okay so even my trivial solution was overthinking it lmao

but it's also two bytes shorter

correction: my solution ported to js beats yours by two bytes, but your solution ported to jelly beats mine by one :P

with actual character i/o

Unrelated String

11:33 PM

oh wait they're straight up complementary

(my original solution was &-65+32)