The Nineteenth Byte

Dennis

03:00

@noɥʇʎPʎzɐɹC Jelly is older than 05AB1E.

noɥʇʎPʎzɐɹC

@ATaco that's almost not english

quartata

@Downgoat High school is lycée by the way

ATaco

u wot m8?

Downgoat

@quartata idk, textbook said collège works too

quartata

At least in the dialect I learned. @TuxCopter would be the person to ask

@Downgoat I suspect that's more ambigious

Destructible Watermelon

03:02

how do I check the name of an instances class in python?

Eᴀsᴛᴇʀʟʏ Iʀᴋ

?

Destructible Watermelon

maybe XY problem

PhiNotPi

IIRC, their educational system is organized slightly differently. Both terms might be correct but refer to subdivisions of something that would normally be considered high school.

Nite to self: phoen typing is hard woth autoscorrect off.

Destructible Watermelon

so, I want a code to do a thing. It should do foobar if it is 1, foo if it is 2, baz if it is an instance of Class A, or Spam if it is an instance of class B. Best way to implement?

class variable is probably best isn't it?

Dennis

It's even harder with autocucumber if you ask me.

quartata

03:04

@PhiNotPi I don't know about grade school level stuff but I'm fairly certain the HS and university systems are not that different

@Dennis what does that entail

Dennis

Downgoat

I added vim mode to client :D

@Dennis XD

quartata

@Dennis Ouch.

PhiNotPi

So I guess it's not that different. College = middle school?

quartata

So kind of like the UK

Dennis

03:08

@quartata Just know that graduate means B.Sc. here, and that I still don't know what a major is.

Downgoat

:O apparently the vim mode even supports :%sor n

Dennis

@PhiNotPi Slightly less complicated than the German system, assuming that paints the whole picture. I like how Gymnasium means high school.

PhiNotPi

@Dennis "major" is a term used mainly in the US, it refers to the subject area an undergraduate student will get his degree in.

Downgoat

TIL rest of the world don't use "major"

PhiNotPi

A "minor" is an additional qualification that an undergrad may choose to pursue in additional subject areas they find interesting.

Dennis

03:11

Well, we don't have any of that here. You study math and that's that.

quartata

That seems a little problematic

Dennis

How so?

PhiNotPi

It is possible for people to have multiple majors (receive multiple degrees) as well as have multiple minors.

quartata

@Dennis No love for CS? :P

Dennis

Well, that's an entirely different career.

They don't even teach it in the same faculty.

quartata

03:14

I guess I don't get the meaning of your message then

I'm assuming your university has more than just a math department

Dennis

You don't choose majors and minors, you choose careers.

PhiNotPi

I guess another way to phrase it is that education is significantly more specialized.

Yodle

I think that depends what you major in though.

PhiNotPi

For certain career paths, the major itself isn't enough and minors are a way for you to choose your "focus." Like, major in international business, minor in spanish.

In my case, major in biomedical engineering, minor in computer science and neuroscience.

I should probably attempt to earn some hats sometime soon.

New Main Posts

-1

Q: Print a Christmas tree of size n

Given a size n, print a Christmas tree as follows. Let's say n is 7. First, I would print a triangle of size 3. * * * * * * And size 4, without the top, while centering the above ones. * * * * * * * * * * * * * * * And size 5. * * * * * * * * * * * * * * * *...

Downgoat

03:31

I am registering downgoat.me... Idk if this is good idea

quartata

Don't you already have vihan.org?

Downgoat

yeah

which is why I am not registering vihan.me :P

PhiNotPi

@Downgoat idea: turn it into a website where people can upload selfies and be turned into goats.

Downgoat

:O

wait nvm I already made that

PhiNotPi

you did?

Downgoat

03:34

vihan.org/p/downgoatify

quartata

Why bother spending money on another domain just because of your meme username

PhiNotPi

I was thinking photorealistic goats.

Downgoat

@quartata no it come for free with education program

quartata

Why not just get vihan.me

Downgoat

cause I already have vihan.org

quartata

03:36

so

.me > .org I think we can all agree

Now if you could get .io

that would be a different story

Downgoat

:/ I'll be kinda redundant having both vihan.me and vihan.org tho

NOOOOOOOOOooooooooooooooo!

Quizlet is down!

New Main Posts

0

Q: Validating user input is giving unexpected results from a while statement in C++

//This is code that needs to be fixed. include include include include using namespace std; // pi is a constant used for the circle calculation const double PI = 3.14159; void calculateCircle(double radius1) //Formulas for area and circumference of a circle. { double areaC; doub...

c++

quartata

Why don't you use paper flashcards

PhiNotPi

@quartata what's up with .io anyway?

Downgoat

@quartata It is hard enough to type, now you suggest I write?

quartata

03:41

@Downgoat Fair cop although paper leads to better retention

Downgoat

> When a Java string does not have surrounding double quotes, what type of error occurs?
a. Syntax error
b. run time
c. compile time error
d. logical eror

can someone explain to be why it's compile time error and not syntax error

@quartata quizlet also has like test generation and stuff tho so I do all my study stuff there

quartata

A syntax error is a compile time error

Downgoat

^ exactly

and most of the time on quizzes you're supposed to be as specific as possible

quartata

Next time ask when you see that. Both answers are correct

DJMcMayhem

@NewMainPosts we keep on closing then, and they keep on coming

Downgoat

03:42

> a. unicode
b. SHA-256
c. EBCDIC
d. RSA

Doorknob

@Downgoat Well, it doesn't necessarily always turn into a syntax error. Consider String s = "10"; vs. String s = 10;

Downgoat

I'm encoding all my messages here in RSA :P

ETHproductions

@EᴀsᴛᴇʀʟʏIʀᴋ No, it was three hours before. Were you thinking about the Philanthropist hat or something else?

Downgoat

@Doorknob ah... ok. thanks :D

DJMcMayhem

I don't understand how someone could think random strangers on the internet will do your work for you

wat

03:42

@Downgoat I have dkudriavtsev.xyz and dk0.us

Downgoat

@DJMcMayhem hey, I participated on SO for a while! :P

quartata

@Doorknob Wow. That's far more sinister than I though a lazy AP CS prof was capable of

Downgoat

@wat good idea

I should get dwngt.me

wat

@Downgoat yeah, I use the second one as file sharing and URL shortening

DJMcMayhem

@Downgoat yeah, I do too. But even SO isn't "it doesn't work. Fix it for me"

Doorknob

03:43

It could also not be an error at all: String s = "someFunctionThatReturnsAString()";

Downgoat

@DJMcMayhem eeehhhh :/

quartata

That's only one char shoter than vihan.org

Geobits

That sounds more like a hindsighted explanation. I mean, "unclosed string literal" is one of the named syntax errors :/

wat

@Downgoat I used this tool to find it: domainnamesoup.com/3letterdomainnames.php

Downgoat

@Doorknob well in this case it won't even be compile time error :P

Geobits

03:44

The question sounds too vague to be worth anything.

@Downgoat Which would make it a logical error I suppose.

Except that it says it isn't surrounded by quotes, not "some other thing is surrounded by quotes".

wat

@Downgoat Set the first two characters to your choice and set the third one to AlphaNum, then press search

You'll very likely find some available ones

Downgoat

:( vb0 is taken

quartata

Darn I just got a hat by accident

Geobits

@Downgoat My best guess is that it's referring to something like this: String foo = bar; which should be String foo = "bar"; instead. In that case it wouldn't be a syntax error, but a compile time error since bar hasn't been declared/assigned.

quartata

two hats actually :(

ATaco

03:48

I need the Taco Hat

ETHproductions

@quartata I'm pretty sure it's impossible to participate in PPCG during Winter Bash without earning several hats

quartata

Can always hit I hate hats

Geobits

I've gotten two without trying also.

Oh, you still earn them. You just don't see them :P

wat

@Downgoat no, vb0.us is availavle

Downgoat

yea but no one likes .us :P

wat

03:52

@Downgoat we're liked...

Geobits

<_<

PhiNotPi

Found a fractal pattern while messing around with infinite resister networks:

1011101010111011
1000101010001000
1011111110111011
1000000010001000
1011101010101010
1000101010101010
1011111111111111
1000000000000000

LegionMammal978

@PhiNotPi Wher iz fractal

Geobits

> I don't even see the code any more...

PhiNotPi

@LegionMammal978 this is the 4th iteration of an infinite thingy.

LegionMammal978

03:54

oh well, I gtg for the night

Eᴀsᴛᴇʀʟʏ Iʀᴋ

@ETHproductions there's a hat for having a positive-score answer to a question, but not getting a bounty that is awarded

but the bounty has to be during winterbash

so does the answer, sadly

@Downgoat oh noes

ETHproductions

"Not getting a bounty that is awarded"? So if someone were to post a question that gets a ton of answers, and then someone posts a bounty on one answer, all other answers on that question with positive score would earn a hat?

DJMcMayhem

Someone should bounty hello world then

Eᴀsᴛᴇʀʟʏ Iʀᴋ

sorta

both the answers and the bounty have to be during winterbash

DJMcMayhem

Boooooh

Eᴀsᴛᴇʀʟʏ Iʀᴋ

03:58

so only brand-new HW answers would get the hat for it

ninja'ed lol

@DJMcMayhem ikr

I'd bounty all of HW, cat, primes, ooh and the showcase

DJMcMayhem

We could snag several hundred hats in one move

ETHproductions

@EᴀsᴛᴇʀʟʏIʀᴋ That's what I get for typing and typing and typing and posting and then looking at the new messages :P

Eᴀsᴛᴇʀʟʏ Iʀᴋ

@DJMcMayhem ikr

@ETHproductions lol

gotta type fast

gotta type sanic fast

DJMcMayhem

@EᴀsᴛᴇʀʟʏIʀᴋ give every single one to Martin so that he can't get the hat. :P

Eᴀsᴛᴇʀʟʏ Iʀᴋ

ouch lol

DJMcMayhem

04:00

I feel like the rep would heal the pain

Eᴀsᴛᴇʀʟʏ Iʀᴋ

also, seemingly there's 2 hats for 1 action? both the sherlock and taco

@DJMcMayhem lol probably

"ooh, dennis has 1.5k more rep to go before he catches me — oh wait now he needs to get 3k to catch me cool"

DJMcMayhem

Actually Dennis still needs 4k. :P

Eᴀsᴛᴇʀʟʏ Iʀᴋ

heyyy @Mego we're tied for first place for PPCG hats

ETHproductions

@EᴀsᴛᴇʀʟʏIʀᴋ What action is that? I don't seem to see either of those hats on the WB page

Eᴀsᴛᴇʀʟʏ Iʀᴋ

secret hats

it's for editing 5 old posts

"Elementary" and "Don't wanna taco 'bout it"

DJMcMayhem

04:02

Do my own posts count?

Also, thanks for the tip! Lol

ETHproductions

Ooooh, that's why Mego edited 5 posts earlier :P I knew he/she was up to something

Eᴀsᴛᴇʀʟʏ Iʀᴋ

so did I lol

@DJMcMayhem nope and lol

89

A: Winter Bash 2016 - All Hats

Secret Hats Live updates on this Google Doc, discussion in this chatroom. Don't Wanna Taco 'Bout it 180° This Is Fine Elementary 8,243,721 6 They Live Blue in the Face Mild Mannered

ETHproductions

Where's the leaderboard?

Eᴀsᴛᴇʀʟʏ Iʀᴋ

winterbash2016.stackexchange.com/leaderboard/…

ETHproductions

Ah, thanks. I'm on the second page at #30, with 1 :P

ATaco

04:03

How do I TacoHat?

DJMcMayhem

@EᴀsᴛᴇʀʟʏIʀᴋ ooh, hammers work for 180. I could cheat and get it by myself. :D

Dennis

You've earned the “decision-problem” tag badge. Didn't even realize we had that tag.

Maltysen

yesterday, by Dennis

The next person who abuses his privileges to get hats will get a suspension instead, until the day after Winter Bash.

:P

ETHproductions

@Dennis I think Mego caused it to form earlier by adding that tag to a bunch of old questions earlier

Ahahaha, Community has the taco hat

5

DJMcMayhem

@Maltysen obviously I'm not (actually|seriously) going to do that

ETHproductions

04:08

I wonder how many hats you could possibly get without posting a single question/answer during Winter Bash

Dennis

@DJMcMayhem Looks like you summoned Mego.

Anonymous

Ugh why was this reopened? It still has the same issue as when it was closed - no specifications on what machine/specs answers will be timed on. People in reopen queues need to read the comments and the question before blindly hitting reopen.

DJMcMayhem

Totally.

Anonymous

@Dennis Haha, a happy coincidence

Downgoat

@Mego probably to get a hat or something :P

Maltysen

04:11

@ETHproductions darth vader, yeti, cut the cord, first responder, epiphany, buche de noel, search you must, dreidel, amped up, 24, grinch, 925, 011, never ending story, bacon, philanthropist,

prolly more

Dennis

@Mego Well, ask Kritixi Lithos, betseg, Easterly Irk, redstarcoder, and Conor O'Brien.

Anonymous

@ETHproductions Yep, we recently crossed the threshold for the badge

Anonymous

@Dennis @redstarcoder @ConorO'Brien @betseg @KritixiLithos @EasterlyIrk explain yourselves

DJMcMayhem

Very ping. Much wow

Dennis

A six-fold ping. Brutal.

Anonymous

04:13

I was really surprised when I got Hero of Questions, and then I realized what had happened.

Anonymous

@EasterlyIrk Did you really make extremely minor edits and then vote to reopen just to get Hero of Questions? Because that's what it looks like.

New Main Posts

0

Q: Find the nearest Date, given a TargetDate and Day Of Week

Find the nearest Date to a TargetDate for a given Day of Week. For example, given a date of Dec 19, 2016 and a day of week of Friday (6), the answer is Dec 16, 2016. For consistency, Sunday is the first day of the week, therefore it is day of week number 1.

code-golf date

ETHproductions

Hmm....

Anonymous

Oh ok, they just didn't bother to read any of the objections

Anonymous

Shame on them still

Anonymous

04:18

I wouldn't be surprised if the edit-and-reopen wasn't motivated by the hat, though

ETHproductions

Oh hey, I'm only 8 points away from the decision-problem bronze badge

Anonymous

I'm still a ways away from that badge :P

Dennis

Huh, after hats, my best guess would have been that they overlooked the fastest-code tag. It would never have occurred to me that someone would actually think that challenge is on topic.

Anonymous

I still smell hat motivations

Downgoat

So french practice test said "On travaille avec les tuyaux"

which translates to "We work with pipes"

10/10 best description of plumber

Dennis

04:21

Anonymous

@Downgoat I thought plumbers ate mushrooms and jumped on turtles' heads

Anonymous

Shows how much I know

DJMcMayhem

@Mego only the Italian ones

ETHproductions

This challenge seems like it should be closed for something, but I have no clue what's wrong

Downgoat

@Mego :O I know how to say this in french

brb moving to france

ETHproductions

04:23

I guess it's just the lack of complete spec and test cases

Um..... Why is this nominated for reopening? It's obviously off-topic, and the only edit was for formatting.

Doorknob

@ETHproductions Editing it automatically tosses it into the reopen queue.

Dennis

> This question was edited after it was closed. Should it be reopened?

ETHproductions

Oh, OK. Now I'm wondering how I've been a part of SE for 1.5 years without knowing that...

Downgoat

Question: Is "je ne veux aucun chose" a sentence that makes sense?

DJMcMayhem

It doesn't make any sense to me, but that's because I'm ignorant and monolingual.

Dennis

04:36

I had a semester of French in high school, but I ran like hell.

PhiNotPi

For those who want to see the resistor network I've been messing around with, go to falstad.com/circuit (a circuit sim) and import this circuit.

Dennis

For some reason, the only word that stuck was parapluie.

DJMcMayhem

You're trilingual right?

Dennis

Pretty much.

PhiNotPi

I'm trilingual if you count English as three languages.

6

DJMcMayhem

04:38

I think it would be really cool to speak a second language but Spanish didn't stick for me

Dennis

I can read Portuguese and understand bits and pieces of Guarani, but the bus stops there.

Anonymous

I know lots of languages. Unfortunately, most of them are programming languages.

ATaco

I speak English, Australian, and Basic German.

Dennis

Well, I rebooted TIO's command mode in case you want to give it a spin. The Escape key is the trigger now, to avoid accidents with copy-pasta.

The unsubscribe link in mails from Let's Encrypt doesn't use HTTPS. o_O

Eᴀsᴛᴇʀʟʏ Iʀᴋ

04:54

@Mego did you post your bounty during winterbash?

for your polyglot piece challenge

@DJMcMayhem ouch lol

@DJMcMayhem lol, let me know if you find a worthy challenge though

multiple people can get this from 1 question

Qwerp-Derp

Yo does anyone know Clojure here?

I speak English, Chinese, Aussie, British and American.

So I'm pentalingual

"Would you like a spot of tea?"

Anonymous

Friendly reminder that I have a 250 rep bounty going, which Martin is currently in the lead for.

Qwerp-Derp

"Oh my gosh, that is so amazeballs"

Just a sample of my extensive vocabulary

Anonymous

@EᴀsᴛᴇʀʟʏIʀᴋ Yes

betseg

I speak Turkish, (Americans don't know what these letters and numbers mean) B2 English, A2 German.

Qwerp-Derp

05:03

What is B2 english and A2 german

@betseg Too much confuse

betseg

Common European Framework of Reference for Languages

The Common European Framework of Reference for Languages: Learning, Teaching, Assessment, abbreviated in English as CEFR or CEF or CEFRL (compared to the German abbreviations GeR or GeRS, the French abbreviation CECR, the Italian QCER, or the Spanish MCER), is a guideline used to describe achievements of learners of foreign languages across Europe and, increasingly, in other countries. It was put together by the Council of Europe as the main part of the project "Language Learning for European Citizenship" between 1989 and 1996. Its main aim is to provide a method of learning, teaching and assessing...

ETHproductions

Anonymous

@ETHproductions Winterbash is programmed in boolfuck

Dennis

@Qwerp-Derp I'm guessing that's the American you mention. :P

Downgoat

haha

ETHproductions

05:11

Refreshed and it's fixed. Must have been caching

Dennis

That or aliens.

ETHproductions

Perhaps it was Darth Yeti.

Dennis

Ooh, shiny new secret hat.

ETHproductions

We're currently 7th on the overall leaderboard, btw, behind SO, Meta, Math, Ubuntu, SU, and ELU

@Dennis Sweet, any idea how you earned it?

Dennis

Not really. It must have something to do with the newest question on main.

Anonymous

05:19

@Dennis You posted two comments, the question was edited, and then you deleted the comments, correct?

Dennis

Yes. I also closed the question and reopened the question.

DJMcMayhem

@Dennis what's it called?

ETHproductions

@DJMcMayhem 8,243,721

Anonymous

Ernie's favorite number :P

Anonymous

@Dennis The nice people in Ye Olde Hat Shoppe request your presence for the purpose of figuring out that hat

ETHproductions

05:31

@Mego Any idea how you earned the taco?

Anonymous

@ETHproductions I earned it with Elementary. I did a bunch of tag edits on old challenges, and one regular edit where I changed only a handful of characters.

Andrew Li

@ETHproductions It has to do with editing

did you view the google doc yet? It's somewhat similar to Elementary

ETHproductions

I've just done 5 tag edits on old challenges, earning Elementary but not the taco.

@AndrewLi Yeah, I have

Andrew Li

Taco criteria is weird.

Any ideas on 8,243,721?

I got 6 for some reason

Anonymous

@ETHproductions I think Taco requires either a non-tag edit with a brief edit summary, or multiple tag edits with no summaries

Anonymous

05:38

But someone confirmed they got Taco only through tag edits so idk

ETHproductions

@Mego I've now done both

Anonymous

We need more distinct hats found on PPCG... I want the participation trophy hat

ETHproductions

brb downloading app to earn more hats

Anonymous

Have we had a challenge to output the sign of a number?

Anonymous

Searching seems to come up empty

ETHproductions

05:48

Can't find any with google. Absolute value, but no sign.

Now I've earned three hats in an hour

Downgoat

Question: when you see log without base specified, do you assume base-2? Base-10? Natural log?

ETHproductions

I usually see log as base 10, ln as base e

Anonymous

@Downgoat Depends on the context. In math, I assume natural log. In CS-related stuff, I assume either natural log or log base 2 (whichever makes more sense in context).

Dennis

Depends on the context. Calculator: 10. Computers: 2. Real analysis: e.

Anonymous

The way I learned was that log was base 10, ln was base e, and lg was base 2. Nobody actually follows those conventions, though.

Downgoat

05:51

Ok. For cheddar I wanna know what log n should

Dennis

We actually used lg for base 10.

Downgoat

O_o

CS book say lg is log 2 like mego said

ETHproductions

@Dennis and sm for base 2?

Anonymous

@Downgoat You should do log for base 10 and ln for base e

Dennis

What's wrong with log10, log2 and loge?

Or ln instead of loge, if you prefer.

Anonymous

05:52

@Dennis What do theater boxes have to do with logarithms?

Geobits

log-1 is more useful than any of those.

Downgoat

Log10 will conpile to like log(10) if that makes sense

Anonymous

@Downgoat It doesn't

Dennis

It really doesn't.

Downgoat

:( ok

Anonymous

05:53

Explicit is better than implicit

Downgoat

Good point

Dennis

It's all but a rule that variables can contain digits, as long as they don't start with one.

Qwerp-Derp

FGITW!

Anonymous

@Dennis But why would you ever have an identifier longer than one byte? :P

ETHproductions

Hat question: Is Philanthropist awarded for awarding a bounty on the last day of the bounty, or the last day of Winter Bash?

Anonymous

05:54

@ETHproductions Last day of the bounty (grace period might count)

Anonymous

Or go full tacit and disregard variables

ETHproductions

I thought it was the former, but the All Hats post says "on the last day of hats"

New Main Posts

0

Q: Output the sign

Given a number N, output the sign of N: If N is positive, output 1 If N is negative, output 0 If N is 0, output 0 N will be an integer within the representable range of integers in your chosen language.

code-golf math number integer

Anonymous

@ETHproductions Wait what? That's... not good.

ETHproductions

I wonder how if I'm the top user on the hat leaderboard who has earned no rep during WinterBash

Anonymous

05:57

@NewMainPosts Gah stupid large fingers and small touch keyboards

Anonymous

I'm kind of amazed we haven't had the signum challenge yet

Dennis

@JonathanAllan I'm actually not sure if I made the edit before you posted your answer. I'll just go back to my previous version and call it Python 3.

Jonathan Allan

Uh Pyth is doing the opposite?

pyth.herokuapp.com/…

Dennis I saw your edited version as soon as I'd clicked submit.

Dennis

OK, if you say so.

You need ._ in Pyth. _ is negative.

Jonathan Allan

The reference says "Sign of A. 1 if A > 0, -1 if A < 0, 0 otherwise."

Oh I didn't notice the ref is 2 chars!

betseg

06:12

Can i change this to #define f(n)(n>0)-(n<0)? Is this allowed?

Hey? :/

Dennis

3

A: What even is a "function" by our standards?

A function is a piece of reusable code that will produce consistent output(s) given consistent input(s). Note that consistent doesn't necessarily mean identical; it merely means that the function won't do something unexpected (i.e. randint(1, 4) will always return a random integer n such that 1 <...

New Main Posts

07:27

1

Q: Solve a Stack State Diagram

A stack state diagram shows how the values on one stack are changed into the other. For example, this is a stack state diagram: 3 0 2 1 0 This means that there is a stack initially containing 3 values (the 3 part). These values are indexed from 0 to 2, with 0 at the top: 2 1 0. The next part 0...

code-golf code-generation stack

Destructible Watermelon

halp

Kritixi Lithos

@Mego I didn't see it was fastest-code, I thought it was code-golf, then I reopened it, then suddenly I saw it became fastest-code

Qwerp-Derp

07:52

Hey kids

I need a game recommendation

Are there any games like Human Resource Machine out there?

Also does anyone want to play a game of Fourtune?

betseg

Me

Kritixi Lithos

me

New Main Posts

08:10

0

Q: Count the number of a number in the picture area

Your goal is to write a full program or function that takes 5 positive integers and a string with an image filename as input [X1,Y1], [X2,Y2], N, image.jpg in any reasonable format, where: First couple [X1,Y1] are the top left X,Y coordinates (<=20) of the blue rectangle area in the example p...

code-golf number image-processing

betseg

Does Mathematica have a built-in for this?

Destructible Watermelon

08:25

hi

Sp3000

@Qwerp-Derp TIS-100, Shenzhen I/O, Cargo-Bot

Destructible Watermelon

@Qwerp-Derp I guess. I'm bored or something

@Qwerp-Derp this is a thing again

Maze battle Koth

making a koth! Please halp

New Main Posts

09:30

0

Q: The Primitive and Basic Numbers

Your task is to generate the "Primitive and Basic" numbers, which are made like so: Start with 1 (base-2), and add the base-2 equivalent of the second prime, which is 11 (3 in base-2). This will give you 100, which is 4 in base-10, which is our first "Primitive and Basic" (PB) number, or PB(1) (...

code-golf math sequence

Qwerp-Derp

Oh no why is chat ded

Wait does no one use the math tag anymore

Zgarb

@Qwerp-Derp I removed it, because I thought it needed base-conversion and primes, and after that math seemed a bit redundant.

Qwerp-Derp

True that

What do you think of the challenge?

flawr

@Qwerp-Derp there is a reason why we have a sandbox

Qwerp-Derp

@flawr I just wasn't bothered for one challenge

Also I was tired from playing too much HRM

flawr

09:43

In my opinion every challenge should have it's turn in the sandbox first

Zgarb

It could use a sentence like "In general, to compute PB(n+1), you first compute PB(n) as a base-n number, then regard it as a base-n+1 number with the same digits, and add the n+2th prime number to that."

flawr

Usually you do put some effort in a challenge and it is such a waste if it turns out that the challenge doesn't work the intended way, even though it could have been fixed. And fixing it after the challenge was posted usually doens't turn out well either.

Zgarb

@flawr I used to skip the sandbox sometimes, but I don't anymore. There's usually something I've overlooked that I want to tweak hours later, even if no-one comments on it.

flawr

Yep, same ehre

Qwerp-Derp

I usually use the sandbox, but IMHO this is a pretty small challenge

Zgarb

09:47

@Qwerp-Derp Also, you should state explicitly that the output is in base 10, with all the base conversions flying around.

flawr

Small challenges aren't any less prone to errors.

Zgarb

@Qwerp-Derp Small challenges can become large once people point out holes in the spec. That happens a lot.

Lembik

hi...low level question. How can I work out what __builtin_ctzll is translated into in assembly?

flawr

@Zgarb Speakign of the sandbox: this came from inverting power series, but it needed too much explanation. The current title was just made up, do you actually know a name for this procedure?

The idea is that you can invert (wrt to composition) formal power series of order 1 by inductively determining the n-th coefficient (mod X^(n+1)) but in order to work well as a challenge I just needed to make everything finite.

Zgarb

If it was 1 mod X^(n+1) instead of X mod X^(n+1), that would be inversion in the polynomial ring R[X]/<X^(n+1)>

Oh wait, it's composition, not multiplication.

flawr

09:53

@Zgarb That would probably work similarly, by inductively finding the coefficients

Qwerp-Derp

Seems like a cool challenge, unfortunately I have no idea what's going on

flawr

@Qwerp-Derp Roughly speaking: You can write any sufficiently "nice" function as a power series (at least in the neighbourhood of a given point)

And you can do the same for the function's inverse.

And we're doing exactly that, but cut off the power series at some points, because working with infinitely many terms is combersome on a computer=)

Zgarb

Okay, I think it's still basically inversion in P/<X^(n+1)>, where P is the ring of all real polynomials, but the ring operations are addition and composition, instead of addition and multiplication.

Qwerp-Derp

I found the challenge spec easier to understand than the explanation here, I think I kinda get it

Zgarb

So "local inversion" seems a fitting title.

flawr

09:58

@Qwerp-Derp I first had a long paragraph for justifying why one might look at that at all, but it just added to much unneccessary fluff=)

@Zgarb I just though for sufficiently small x the x^(n+1) (and higher order) term disappears in comparision to x

@Zgarb Does this still actually form a ring?

Maze battle Koth

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