The Nineteenth Byte

Nick Clifford

3:13 PM

Which value is uninitialized?
It all looks fine to me.

Lembik

hi all

feersum

@NickClifford Try looking again ;)

Or have the compiler look for you.

I'm trying to make an ML compiler and realized one situation is really tricky.

If I have something like let x = (print_string "h"; []) in (3::x, true::x)

Then x has two different types, int list and bool list.

Lembik

posted codegolf.stackexchange.com/questions/112649/… . Any quick comments very gladly received

feersum

But if I naively compile the whole expression for x twice, I get two prints, which is wrong.

So how do I do this...

Maybe I will just duplicate the expression for x since doing it correctly would be a ton of work and yet rarely used.

Lembik

@ETHproductions Hi .. are you here?

ETHproductions

3:24 PM

@Lembik Yes

Lembik

@ETHproductions but then it becomes a fastest code challenge

and it has to run on my machine

ETHproductions

Yes, that's the problem...

Lembik

I have done a lot of those

but I was hoping to avoid it this time

ETHproductions

Because it's possible to write a solution that's completely optimal, the challenge is basically a race to write the optimal solution

Lembik

@ETHproductions well no because you won't output anything

ETHproductions

3:26 PM

I'm not sure what you mean...

New Main Posts

0

Q: Count how many output arrays are far from all other arrays

Let P be a binary string of length n and T be a binary string of length 2n-1. We can compute the n Hamming distances between P and every n-length substring of T and put them into an array (or list). Now let's consider two such arrays of Hamming distances. Say x = (0, 2, 2, 3, 0) and y = (2, 1, ...

ETHproductions

@Lembik Why won't it output anything?

feersum

Hmm, maybe a correct way to compile it would to replace all polymorphic expressions with an n-tuple containing the correct value for each of the n types the let binding is instantiated with.

Lembik

sorry I have to dash

feersum

This could get very hairy if the let expression's type has multiple free variables...

Maybe instead I could do a hack where one instantiation is compiled with the functions that have external side effects included, and in the other ones those functions are replaced with no-ops.

Jan Dvorak

3:47 PM

I should probably start actually posting bubblegum answers to kolmogorov questions... :-) (as CWs, don't worry) — Jan Dvorak 20 secs ago

Nick Clifford

@feersum I'm not sure what there is to see. The smaz_compress function is defined in a header and output and len are both defined.

feersum

@NickClifford output is defined? citation-needed

Nick Clifford

>char* output = "";

Might need to refresh the page, since I just added the empty string bit.

feersum

That's rude to change the question without warning.

Nick Clifford

Whoops

Question still stands, though

feersum

4:00 PM

So now output is initialized, but to a value which is entirely inappropriate for how it appears to be used.

Nick Clifford

>`int smaz_compress(char *in, int inlen, char *out, int outlen);`
From the header file

feersum

With an unforgiving language like C, it's good to learn the basics before trying to use it.

You're not going to get a helpful and informative error when you make mistakes.

Dennis

No kidding. Segmentation Fault is C's BSOD.

feersum

Learn about pointers, memory allocation, etc

Nick Clifford

Hmm, alright

I thought I understood pointers, but I guess not

Dennis

4:08 PM

26

A: How should Community Wikis be used?

Community wiki is not a rep waiver I've mentioned that from time to time in the past. Community wiki doesn't just mean that you cannot earn rep from a post. Yes, it does have that side effect, but the community wiki option is for posts that can be edited by anyone without worrying about post ow...

feersum

Seems appropriate -- it's an answer that involves no programming or other work.

Dennis

The problem isn't getting rep from no-effort answers. The problem is that they shouldn't be upvoted in the first place.

feersum

The latter problem isn't actionable.

Dennis

If anything, making it CW will attract more upvotes. A few undeserved internet points don't matter. What matters is that these posts shouldn't sit at the top.

Nick Clifford

Ah, I see, I just had to figure out memory allocation

Jan Dvorak

4:17 PM

@Dennis I take it I should take credit for - and reap reputation by - feeding the question input into gzip? I can do that.

Dennis

It's arguably more work than posting an answer that consists of a single built-in...

Jan Dvorak

Do you have stats on how much CW vs. non-CW affects the vote count?

I could argue that answering with builtins is just as cw-worthy as a bubblegum answer.

Dennis

It's just as undeserving of rep. I'm arguing that CW isn't a rep waiver and, at least in my opinion, shouldn't be used as one.

CW is meant to be used for answers that can be improved by the whole community. There's no room for improvement in a 1-byte answer, so CW doesn't serve its purpose.

betseg

there should be another answer category :P

Dennis

@JanDvorak Hard to do. Most CW answers belong to very old or very popular questions.

feersum

4:24 PM

Let's do a randomized controlled trial.

Jan Dvorak

is CW even being used for its intended purpose?

betseg

on some tips questions, yes

Dennis

Yes, the Showcase of Languages is our most prominent CW thread.

Sherlock9

@Mendeleev You don't need to ping me with every reply. As a matter of fact, I'd prefer it if you didn't ping me with every reply

Unless you are replying much later like I am

Wheat Wizard

4:48 PM

Could someone answer the newest answer-chaining question? I have so much I want to do but I can't answer because I was the most recent answerer.

11

Q: Answer-Chaining - Positive divisors of a number

This an open answer-chaining challenge, so your answer depends on the one before yours. Task: Print all the positive divisors of a number x taken as input. Input: A single number x which is the number (in base 10) whose positive divisors should be computed. Output: All the positive divi...

math number arithmetic printable-ascii answer-chaining

DJMcMayhem

5:00 PM

@WheatWizard I'll look into it later today. I'm not positive I'll be able to answer it, but I'll definitely try

Wheat Wizard

Thanks

DJMcMayhem

But if I have leftover edits, I'll remove brackets. :P

(jk of course)

Conor O'Brien

5:12 PM

@WheatWizard I probably won't have the language that I was planning to do done before the bounty expires, just FYI

Wheat Wizard

Ok, too bad. I was hoping to see it before the bounty expired. You still have 2 days though so GL. And if its really good I might start another bounty

Conor O'Brien

thanks! rn I'm doing some research for the program

PhiNotPi

5:37 PM

@WheatWizard I might have a go at your challenge.

IDK if it will be done in time. What's the bounty grace period?

Wheat Wizard

24 hours

PhiNotPi

yeah I strongly doubt my ability to come up with anthing good within the next 2 days or so

Got an exam on Tuesday as well.

Conor O'Brien

good luck!

Mistah Figgins

6:26 PM

@WheatWizard What's with all the s?

What character are they?

Wheat Wizard

What s?

Mistah Figgins

On my screen, there is a box there

Can you see this character?: ""

Wheat Wizard

Oh its a carriage return

It doesn't appear for me

its just a special type of whitespace

Mistah Figgins

Ah, got it

betseg

it doesnt appear for me too, googling it shows "?"

Mistah Figgins

6:29 PM

Why does your del|m|t answer have so many at the beginning?

Wheat Wizard

Thats the code.

Kritixi Lithos

@betseg Vim shows it as "^O"

Wheat Wizard

I used carriage returns because the question says they don't count towards the difference

Mistah Figgins

Ah, got it

Wheat Wizard

They are delimited by spaces

Mistah Figgins

6:30 PM

That makes it easy, I guess

It confused me, because you added so many

betseg

just noticed that command<C-O> in a terminal runs the command

Mistah Figgins

Newlines count as whitespace, yes?

betseg

> In computer science, white space is any character or series of characters that represent horizontal or vertical space in typography.

so, yeah

Jan Dvorak

What is the zero-width word joiner then?

Downgoat

6:50 PM

Question: does this or this design look better?

(just talking about icon colors)

Fatalize

blue star is strange

Mistah Figgins

I like the first link's colors (yellow star) better

But you should line up the icons with the left

Downgoat

does purple fork look weird?

Kritixi Lithos

@Downgoat That logo...

Mistah Figgins

I think it is probably fine

Kritixi Lithos

6:52 PM

But I like the second one better

Downgoat

I think information density might be too much

Kritixi Lithos

I meant the first one

Downgoat

Should it be "0 <star icon>", or should I keep it the way it is now ("<star icon> 0")

0 being the number of stars

Mistah Figgins

I would put it 0 <star> because that way the stars will line up, even if the numbers are different sizes

Downgoat

ok, good idea

Mistah Figgins

6:57 PM

Apparently, Befunge-98 treats carriage returns as reflectors

But normal Befunge doesn't

Kritixi Lithos

@Downgoat I think it would be better if you give more importance to the name of the repo than the person who owns it

Downgoat

@KritixiLithos hm, ok, will fix

Mistah Figgins

^^

Downgoat

Hm, this could mean you won't see the username (only avatar) if repo name is really long, is that OK?

Mistah Figgins

Possibly tap on icon to see author

I think it's fine

Kritixi Lithos

7:05 PM

Or to keep it constant, why not remove the username totally, so that only the avatar and repo name will be visible. And ^^

Downgoat

@MistahFiggins oh, that is good idea too

Albert Renshaw

About two weeks ago someone introduced me to the [code-bowling] tag and I was pretty intrigued but I was sad to see that almost all of the code-bowling challenges that had been proposed had been closed for various reasons.

Typically these reasons were because the post was too broad, allows for almost every answer to be ∞ bytes, lacked a clear scoring system, had unenforceable/vague rules, etc.

I'd like there to be more code-bowling challenges on CG but it seems that there are very few resources for how rules should be defined in a systematic manner, what style challenges should be propose…

New Meta Posts

0

Q: Code Bowling Index

Author's note: This is a meta post tagged with discussion. The goal of this post it to create a community-wiki for Code-Bowling. Please post suggestions / concerns as answers and feel free to utilize the comments section on this post as well as on answers to discuss the topics at hand. (For ex...

discussion code-bowling

6

Mendeleev

7:29 PM

Slow Motion Contact Explosive - Nitrogen Triiodide

►

betseg

how he pronounces nitrogen bugs me

or soft gs in general

Lembik

hi all

operation rescue-question starting :)

Riker

worst idea of the day: #define in java

Григорий Перельман

That is an excellent idea, what are you talking about?

Conor O'Brien

>_> I told him about my new language which is basically ^^

Lembik

7:43 PM

hi @ETHproductions

are you about?

Downgoat

Григорий Перельман

No, it would totally be awesome.

Downgoat

Okay, made some tweaks to repo view, hopefully looks good

Григорий Перельман

Yeah, looks good.

Still a lot of empty space on the bottom

Jan Dvorak

Some I'm not a fan of all those screenshot oneboxes

Downgoat

7:46 PM

@Riker this is good idea, but make sure to make it

new MacroFactory(new MacroTypeFactory().getMacroTypeFactoryFromString().newMacro("define")).setName("‌MAIN").setValue("public static void main")

@ГригорийПерельман yeah, will replace with README

Lembik

how do you search for everything said by a person?

it seems you can search for something specific said by a person in chat

Григорий Перельман

Anyone have the link to Starman's TNB Data Explorer?

Lembik

but how do you search for everything?

Downgoat

@Lembik I believe you'll have to use the TNB Data explorer

@Lembik ppcg.starmaninnovations.com/tnbde/#PCckjsiQWV

Lembik

I have no idea what that is :(

betseg

7:49 PM

SQL

Kritixi Lithos

@Downgoat Maybe 1 watching instead of 1 watchers (not worried about the s btw)

Riker

it's an sql client that searches TNB messages

Downgoat

@KritixiLithos oh good idea, screw pluralization

Lembik

ppcg.starmaninnovations.com/tnbde/#NvXHlJcXIp :(

I just want to see something ETHproductions wrote to me

Downgoat

@Lembik oh

go to ETHProduction's chat profile

Conor O'Brien

7:50 PM

> Chat ID

Downgoat

@Lembik here's a list: chat.stackexchange.com/users/155790/ethproductions?tab=recent

Lembik

thanks!

@Downgoat hmm.. does that only give me one page?

Riker

looks like it :(

Downgoat

@Lembik add &page=2 to end of url to go to page 2

Riker

also @Lembik was it a reply/ping to you? then you can try chat.stackexchange.com/…

chat search for "@Lembik" by ETH

Lembik

7:53 PM

sadly I don't think he/she added @lembik every time

New Sandboxed Posts

0

A: Sandbox for Proposed Challenges

Monitor your ARP table This is code-golf The Address Resolution Protocol is used to associate IP addresses on the local network with hardware addresses (aka MAC addresses). In its most basic form, ARP can be very insecure in the sense that your computer will believe anyone on the local network ...

Lembik

ok here is my new improved question codegolf.stackexchange.com/q/112649/9206

please take a look

any upvotes hugely appreciated :) I fear the negative numbers

Григорий Перельман

Is there a way to filter pull requests on GitHub by if they were merged or rejected?

Jan Dvorak

I'm sorry, asking for upvotes simply doesn't fly here on SE...

Lembik

@JanDvorak I completely understand. I wasn't being serious but I still won't do it again. I was just joking about how sad negative scores make me

Maltysen

8:02 PM

i feel like this might be a dup: codegolf.stackexchange.com/q/112663/31343

but can't find anything

Lembik

@JanDvorak but I would hugely appreciated detailed comments on the question

I have tried to make it clear

New Main Posts

1

Q: Random substring generator

Generate random substring of length k from a given string with equal probability. For example, string tree has 7 substrings with length of two, tr, te, ee, rt, et, re, er. The function should return any one of them with the probability of 1/7

code-golf random

Riker

8:21 PM

@flawr r/MURICA

some language

Lembik

I hope people reread my question now it is fixed.

Or maybe I should delete it and repost?

Mendeleev

I feel like this website uses Material Design really, really well

Riker

9

@Mendeleev yeah

flawr

@Riker similarfor switzerland: /r/BUENZLI

Maltysen

@Riker that cursor

Conor O'Brien

8:46 PM

@flawr you know haskell right?

flawr

@ConorO'Brien A little bit, yes.

betseg

@fergusq or for num in {1..5}; do ...; done

Conor O'Brien

ok, so I'm just learning haskell, and am trying to reverse the input. I have the following, but this adds quotes. I tried print, putStr, etc. instead, but none have worked. What might I use instead?

f s = reverse s
main = interact (show . f)

flawr

Hm I'm a bit rusty, let me check.

Jan Dvorak

@ConorO'Brien Hint: what does showing a string do?

Conor O'Brien

8:53 PM

@JanDvorak it outputs the representation of a string

Jan Dvorak

What is the string representation of a string?

Conor O'Brien

a string?

oh

oh ok

interact outputs for you, lol

Jan Dvorak

interact :: (String -> String) -> IO()

flawr

@ConorO'Brien this?

Jan Dvorak

putStr is the most basic one - just string -> IO(), and print = putStr.show

flawr

8:58 PM

And yes, the show is not necesssary as you already get a string from reverse

f = reverse
main = interact (unlines. map f . lines)

Conor O'Brien

ohhh ok

thanks @Jan @flawr

Maltysen

does anyone know a faster way to get a permutation of 1..n than fisher yates?

it doesn't have to be perfect, i'm just using it to statistically simulate an algortihm

flawr

@Maltysen Isn't fisher yates O(n)?

Jan Dvorak

->x{x}, AKA :itself.to_proc

Maltysen

@flawr yeah, but doesn't need to be asymptotically faster

maybe something without as many rand() calls or something

flawr

9:00 PM

Ah well rand() is usually quite slow, why don't you just implement your own rand?

Jan Dvorak

You could try computing the rand(n!)-th permutation

Maltysen

is linear congruential good enough?

@JanDvorak hmm?

flawr

@Maltysen Depends on what you want....

Maltysen

true... I'm just simulating an algo to get expected storage use

and shuffling it to get kinda the input for each run

flawr

I think then it should be sufficient.

@ConorO'Brien You could also use getLine instead.

betseg

9:43 PM

>>> print(a + b + " = " + c)
ab = 0
>>> exec(a + b + " = " + c)
>>> print(exec(a + b))
None

am i doing something wrong?

xnor

exec does the thing and outputs None, same as print

betseg

oh

Down Christopher

@Betseg your profile image

That is a crime

betseg

lol

New Main Posts

-1

Q: How to rotate a matrix clock-wise in place by ninety degrees

I asked this question in both the SO and Comp Sci stack exchanges and got shot down for being too open ended in the former, and not using pseudo code in the latter. Hopefully this is the right exchange! So the question is: Given an NxN matrix represented by nested arrays, write a method w...

java ruby

Down Christopher

10:01 PM

@Newmainposts i edited it to make it a real challenge if the edit is accepted that would be enough to reopen i think

Григорий Перельман

@DownChristopher Then it would be closed as duplicate instead of off-topic.

Down Christopher

@ГригорийПерельман Little better

Григорий Перельман

Don't polish turds

Jan Dvorak

What if I can polish them into a gem?

Григорий Перельман

Feel free to, but this one isn't salvageable.

Down Christopher

10:08 PM

:P I tried my best. I am trying to make it look a little better so if it is found by google or something it would look better on the community

betseg

reddit.com/r/SubredditSimulator/comments/5ys067/… oh shit shut r/SubredditSimulator down

Григорий Перельман

@betseg I can't access reddit, what is it?

Down Christopher

Funny stuff

Zwei

Top Democrat sent letter to president Donald Trump of violating the constitution

links to a screenshot of a tweet by Scott Dworkin

Григорий Перельман

Who's Scott Dworkin?

Down Christopher

10:14 PM

Guys wth this yt video only loads in 720p hd 60 fps... I have crap net

betseg

It's a subreddit that only bots can post. That bot posted "Top Democrat sent letter to president Donald Trump Of Violating The Constitution", with an image of Scott Dworkin's tweet about Trump's removal of Obama's heathcare

Zwei

seems like the head of some democratic PAC

Григорий Перельман

I know what /r/SS is

But that's pretty good.

betseg

@ГригорийПерельман :s

Jan Dvorak

@DownChristopher first world problem...

Down Christopher

10:17 PM

@JanDvorak I KNOW THIS IS A REAL PROBLEM please halp

Jan Dvorak

Buy a smaller monitor

3

betseg

@DownChristopher tfw i can load 480p if im lucky ;_;

Down Christopher

instagram.com/p/BRfADRsjoVD

Григорий Перельман

Is there a way to force it into 30 FPS? I want higher resolution but I don't particularly need the higher frame rate.

Down Christopher

nope

Jan Dvorak

10:18 PM

Youtube+ can disable 60fps

Down Christopher

The only resolution available is 720p hd 60fps so i can't change anything

Григорий Перельман

Hm, I'll look into it.

Jan Dvorak

@DownChristopher impressive, but the screenrip ruins it.

Down Christopher

Yeah

Jan Dvorak

but yeah, videos from photorealistic games should definitely be in FullHD at least.

Григорий Перельман

10:23 PM

@JanDvorak *Buys 7 inch 4K monitor*

Jan Dvorak

@ГригорийПерельман it's called an iPad mini

Григорий Перельман

Is it actually 4K?

I thought I was being satirical.

Jan Dvorak

it certainly has way more DPI than is practical

Retina displays have so much screen resolution that the OS has to pretend to the apps it's only half as much, otherwise everything would be unuseably tiny

Григорий Перельман

o.0

Down Christopher

Yeah if i need a microscope to view pixels I CAN'T TELL THE DIFFERENCE IF THEY ARE EVEN SMALLER

Григорий Перельман

10:29 PM

@JanDvorak But then what's the point of having so much screen resolution in the first place, if you're just going to display at half that?

Jan Dvorak

The real trick is to have black and white pixels spaced about 10nm apart, a laser shining onto it and a really good GPU

TuxCopter

This /r/SS post is beautiful

Jan Dvorak

@ГригорийПерельман the apps that know about retina have a special command to say "hey, stop pretending"

the UI is still positioned using 2x coordinates, but the render buffers are four times as big. Unless I'm inventing stuff incorrectly.

The UI components are still crisper on retina displays, even if their user app doesn't know that.

I tried looking at the wiki article but without success regarding the technology

> Apple introduced the 2012 MacBook Pro with a resolution of 2880×1800 or 5.2 megapixels - doubling the pixel density in both dimensions.[2] The laptop shipped with a version of OS X that provided support to scale the user interface twice as big as it has been previously been.

In other words, it just scales up the UI components twice as big.

Григорий Перельман

Oh, I remember that! Apparently the GPU would thermal throttle even without needing to open any apps.

Jan Dvorak

Sounds fun. I'd rather buy an actual hair dryer

Downgoat

10:45 PM

does anyone happen to have a repo on GitHub w/o a readme

Григорий Перельман

@Downgoat Yes: github.com/PavelBraginskiy/KerbalSpaceProgramming

It's an old abandoned project of mine.

New Sandboxed Posts

0

A: Sandbox for Proposed Challenges

Quandle Quandary Episode I: Identifying Finite Quandles Write a program that will determine if a given matrix represents a quandle. A quandle is a set equipped with a single (non-commutative, non-associative) operation ◃ which obeys the following axioms: The operation is closed, meaning that ...