The Nineteenth Byte

lyxal

01:00

@RydwolfPrograms in relation to this suggested edit review, I just thought it was worth mentioning that the 💎 needs to be inside the code box. Nothing major, just something to know for future review events

Because having the 💎 inside the code box gives consistency and leeway for any meta data changes that could be made

(it acts as a nice selection point)

Rydwolf Programs

ah, mb. To me the edit mostly just looked like it added the link to Lumenspire, didn't realize it also messed with the code

lyxal

As I said, nothing major and easily fixable (there's nothing at the bottom of the block yet anyway)

It's also a heads up for everyone really

Hm maybe I should add some HTML comments in the generated markdown saying to be careful with edits

That's probably a good idea

Ooh and the html comments could also include a permalink for easy editing rather than having to copy paste into the import button (not that the link would replace the meta data because you might have cases where it's easier to copy the explanation text rather than go to the post source)

l4m2

04:12

codegolf.meta.stackexchange.com/a/25851/76323 Any theory wrong?

mousetail

04:59

@Simd It will return what letters appear in the greatest number of words. I have no idea if it's the shortest.

This might be slightly shorter: lambda x:max((y:=sum(map(list,map(set,x)),[])),key=y.count)

New Posts

I would like some apple flavoured butter please.

lyxal

05:14

I use Android you doofus

Simd

@mousetail could you explain the code please. It is confusing me

mousetail

@Simd Convert each word to a set to remove duplicate letters, then concatenate them all into one long string, then take the item that appears the most often in that string

Simd

Very nice!

The sum is the first mysterious part to me

It concatenates the lists somehow

Why do you need the []?

mousetail

05:37

Because otherwise you can't add 0+[]

Simd

Where does the 0 come from? We are just adding lists aren’t we?

Ah docs.python.org/3/library/functions.html#sum

at least that is resolved :)

Simd

05:54

Now I just have to understand max….

Sandbox Posts

07:20

0

A: Sandbox for Proposed Challenges

Compute 0.1+0.2+0.3+...+0.8+0.9+0.10+0.11+0.12+...+0.[n] Sandbox Note Dupscanner

l4m2

@SandboxPosts Can't find anything by searching 0.1+0.2+0.3

mousetail

Does that constant have a name?

10

A: Things to avoid when writing challenges

Real-valued output without further specification, or with a bad one For integer outputs, you can check correctness with exact equality. For exact fractions, many challenges require to output a (numerator, denominator) pair which has worked out pretty well in practice. But for real number outputs,...

l4m2

It'sinfinity when n->oo

so an upperbound is necessary

Adám

07:34

@Simd ∪¨⎕ removes duplicates from each input, ⊣¨⌸∊ flattens and bins characters into a matrix of rows of identical characters, padding short lines with spaces, ' '~⍨⊢/ selects the rightmost column and removes spaces from it, ⊃ picks the first.

RubenVerg

08:23

@Adám nice, I had {A[⊃⍒+/⍵∘.∊⍨A←∊⍵]}, always forget about Keys

@lyxal could you explain t he edit on my answer related to luminespire? why does one diamond go inside the block, and one outside? also I thought I just pasted the result from the tool, but maybe I messed something up :)

Adám

@RubenVerg ∘.∊ is just an obfuscated ∘.= right?

RubenVerg

no, because the input is a vector of vectors

I'm tabling whether each letter appears in each string

mousetail

08:38

@Simd You know math right? Can you tell my why sum x=1 to infinity of` x/(c^x) = c/(c-1)^2`. Or what this general category of formula is called so I can search it better

Adám

@RubenVerg Ah, I see.

lyxal

@RubenVerg so what happened there was that someone suggested a formatting edit to make the link an actual hyperlink. However the edit placed the diamonds outside the code block. So instead of rejecting or accepting, I clicked the "improve edit" button and moved one of them back in the code block

I must have missed the second one

And because I clicked improve edit, it attributed the edit to me

RubenVerg

right, I see, thanks for clarifying, I'll edit the second one as soon as I have time

lyxal

Luckily it's still just a quick fix :p

RubenVerg

@mousetail I don't think this has a name but I could prove it

mousetail

08:52

That would be helpfull

I noticed wolfram alpha can solve it even for more complex variants but it won't tell me how unless I pay

RubenVerg

I hate doing latex on mobile, as soon as I get to my computer I'll sketch a proof

mousetail

I'm just curious, I don't need this for anything. No rush

Simd

09:08

@Adám interesting. I can't even tell why that gives the right answer

@mousetail they are geometric sums I believe.

mousetail

The ratio is not always the same though

Simd

Right... Hmm

RubenVerg

09:24

@Simd it's the derivative of the geometric series with an extra c term

Adám

09:49

@Simd Does this help?

l4m2

Why someone is randomly caring about case when n=10^17?

RubenVerg

10:14

@mousetail here you go

forgot to crop it oops

PlaceReporter99

@SandboxPosts lambda x:sum(eval(f"0.{y}")for y in range(x+1))

RubenVerg

this is better

this is definitely not rigorous but hopefully good enough

also, this obviously converges only for z\not\in[-1, 1]

PlaceReporter99

try online my python solution

RubenVerg

oh also I think you could prove this without calculus but I'm lazy and derivatives of powers are like 16yo calculus

PlaceReporter99

10:30

@mousetail Try online

mousetail

@RubenVerg Thanks

l4m2

@PlaceReporter99 f=lambda x:x and eval(f"0.{x}")+f(x-1) Recursive shorter

RubenVerg

11:03

@mousetail there are two mistakes which cancel out, I just noticed

f(x) is 1/(1-x), and I forgot a minus sign in the derivative

so the derivative is actucally correct

Simd

11:23

@RubenVerg I had that thought too

Sandbox Posts

11:47

0

A: Sandbox for Proposed Challenges

Tic-Tac-Toe: Maintain the Draw! Tic-Tac-Toe is a game for two players who take turns marking the spaces in a 3x3 grid with an X or a O. If a player succeeds in placing three of their marks in a horizontal, vertical or diagonal line they are the winner; otherwise, the game is considered drawn. Cha...

New Posts

14:49

0

Q: Continuously Count Consecutive Cases

Background Imagine that I'm creating a really long necklace, consisting of only two characters, A and B. You must count the number of occurrences of the substring AB in the string. However, since it's a necklace, you must also consider if the last character and the first character join to make AB...

code-golf

Simd

Hello!

Adám

Hi!

DLosc

15:33

@Simd Pip, 16 bytes: @:-#{aN_FI\g}SKz

Might be golfable using a different approach

15 bytes: @:#{aN_FN\g}SKz

The Thonnu

Invalid, right?

"HTML pages don’t suddenly stop while you’re browsing them…"

RubenVerg

@TheThonnu depends on how lax the requirement is

The Thonnu

I'll skip the review and leave it to someone else

The Thonnu

15:51

Reminder to reviewers that invalid answers should not be VLQ/NAA flagged; vote "Looks OK" and mod flag. — Rydwolf Programs 3 mins ago

^

Simd

@DLosc cool!

Adám

> Reminder to reviewers that invalid answers should not be VLQ/NAA flagged; vote "Looks OK" and mod flag. — Rydwolf Programs

5

New Loophole Proposal

18:13

Loopholes that are forbidden by default - Code …: Answer by I am kind of a language dev for Loopholes that are forbidden by default

posted on July 17, 2023 by I am kind of a language dev

Outputting a Lazy list/Lazy data type in fastest-code challenges This just moves the computation to after runtime. For example, in Python, the code: def f(): return 492084389428**209480438084, 6356425635**23984723879 takes a very long time to run. However, if you use the yield keyword to generate a Lazy List: def f(): yield 492084389428**209480438084 yield 6356425635**2398472387…

Sandbox Posts

18:41

0

A: Sandbox for Proposed Challenges

Decimal to fraction In the pool of questions on CGCC, I have not found a question with this task. Given a float in base 10, output a fraction in simplified form, improper or mixed. The output format can be any reasonable one. In code-golf, the shortest answer wins! Test cases 3.5 -> 7/2 or 3 1/2...

The Thonnu

20:04

@SandboxPosts Vyxal, 0 bytes lol

Bbrk24

not even any flags?

The Thonnu

Nope, Vyxal's normal number representation is rational

Which is exactly the output format of the challenge

That did probably inspire the challenge (since PlaceReporter has been doing a bit in the Vyxal organisation recently)

And anyway it's a duplicate: codegolf.stackexchange.com/q/17239/114446

c--

20:47

@emanresuA I'd expect most interpreted languages to have some form of --help of --version

I just followed the transcript link from the sandbox, didn't realize the message was so old

Simd

21:55

Hi all

lyxal

22:07

@TheThonnu woo! Finally a benefit of using Sympy for everything and having to have dealed with all the cringe that library has caused! :p

DLosc

22:46

@lyxal Could you please unfreeze The Tarpit?

lyxal

As you wish :p

DLosc

(If it's a tarpit, maybe "unfossilize" is the better analogy? Hmm.)

lyxal

As you wish :p

DLosc

Lol

When you ran for PLDI mod, did you anticipate that it would lead to an increased workload on CGCC also? :P

lyxal

Kinda lol

I knew I'd still be around here so I knew I'd be able to do chat support stuff

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