The Nineteenth Byte

ATaco

8:00 PM

I now have GitGoat Beta, and I'm rather impressed by it.

Riker

hm, I'll try to install it later

mbomb007

Do you think I could make a new/better challenge, since the following comment has lots of votes?

Have case-insensitive output while banning the language name case-sensitively allows boring solutions that just output the language name case-swapped. — xnor Jan 25 at 0:47

Riker

@mbomb007 hm, not sure

AdmBorkBork

@flawr @HelkaHomba It also depends upon how humid it is the particular day you're doing it, whether the setting is in the shade or the sun, whether you're expecting rain, etc.

Riker

I think it would need something more than just that though

@flawr you belong in r/theydidthemath

also, @ГригорийПерельман and flawr: do you prefer r/sub or /r/sub syntax?

flawr

8:09 PM

@Riker definitely /r/sub

Riker

heresy

flawr

@Riker /r/theydidthemonstermath

Riker

r/ is golfier plus easier

@flawr r/itwasagraveyardgraph

flawr

@Riker haha, high 5 :D

Riker

:D

@flawr also -1 matrix of ones != identity matrix ;-;

flawr

8:12 PM

hu?

Riker

hw for this week is matrix review

it's a pita that the identity matrix isn't just all ones

flawr

Much nicer, it's a diagonal matrix :)

AdmBorkBork

It can't be all ones, else you wouldn't get the identity back out when you matrix multiply

Riker

@flawr true

@AdmBorkBork yeah I understand

-1 math doesn't work in simple ways ;p

Kritixi Lithos

I only truly understood why the identity matrix was diagonal from watching 3b1b's videos

AdmBorkBork

8:14 PM

> math doesn't work in simple ways

Understatement of the millenium

Jan Dvorak

How can you say that in the same sentence as "-1"?

Riker

@KritixiLithos I completely understand as of yesterday, helps a ton to work out the inverse of a matrix [a b; c d] algebraically

@JanDvorak because i have the flu and am perpetually tired

mbomb007

@Riker Yum

flawr

@Riker What do you call it if someone removes a zero matrix with ones on the main diagonal against your will? identity theft

3

Riker

ok you get star for that

10/10

flawr

8:16 PM

:D

mbomb007

What do you get when you cross a mountain climber and a mosquito?

Nothing, you can't cross a scalar with a vector.

Kritixi Lithos

A mosquito climber

Riker

@mbomb007 not as good as his

flawr

@mbomb007 What does the verb cross mean in this context?

Riker

@flawr are any diagonal matrices other than the identity and scalar ones interesting?

@flawr to combine

DJMcMayhem

8:17 PM

@flawr synonym for combine

Riker

i.e. "what do you get when you combine a mountain climber with a mosquito"

@DJMcMayhem ninja'ed

DJMcMayhem

@mbomb007 I don't get the "vector" part. >_<

flawr

No i mean the math meaning?

Riker

@DJMcMayhem I thought it was a play on "vexer", i.e. something that vexes

mbomb007

Because a mosquito is like a small point with nothing but a direction and magnitude

Riker

8:18 PM

@flawr oh true

@mbomb007 vectors have a magnitude though

it should be scalar + scalar

lel

DJMcMayhem

Also, does that make me a scalar?

Riker

yes

Doorknob

@DJMcMayhem Oh, I thought it meant like a vector for disease. We all interpreted this differently. :P

Riker

congrats you're now a scalar you get a snazzy medal of coolness

mbomb007

Idk. The joke was from Calc 3

Riker

8:19 PM

@Doorknob that got dark fast :P

flawr

@Riker Well as soon as you learn about diagonalization of matrices you're goign to appreciate diagonal matrices :)

Riker

hmm okay

mbomb007

What do you get when you cross an elephant with a grape?

DJMcMayhem

@Riker Yay! \o/

mbomb007

Elephant Grape Cos(Theta)

Riker

8:19 PM

@flawr maybe the cross product of the matrix (i.e. vector) and scalar matrix of the scalar?

DJMcMayhem

@mbomb007 woosh

mbomb007

unless it's Sin(Theta)... I forget

flawr

Ah so cross = cross product = vector prodcut?

mbomb007

@Riker Yeah

Riker

I guess so yeah

@DJMcMayhem same :p

mbomb007

8:20 PM

@DJMcMayhem Yeah, it's a whoosh for me, too. It's been too long.

Григорий Перельман

@Riker /r/sub

Riker

:( everybody is a heretic it seems

@mbomb007 i did that last year and it's still a woosh :P

DJMcMayhem

@mbomb007 it can't be a woosh for you, you were the one who posted it! Lol

Riker

@ГригорийПерельман what's better about /r/?

DJMcMayhem

Riker

8:21 PM

@DJMcMayhem apparently your argument is flawed

mbomb007

Darn. It's sine(theta)

I was wrong

Math jokes

Григорий Перельман

Nothing's better about it, I just prefer it that way.

Doorknob

@DJMcMayhem Hah, that reminds me of the "sin gerine / cos gerine" one.

Riker

@ГригорийПерельман hm ok

DJMcMayhem

Ha, that's a good one too

Riker

8:22 PM

despite r/ being golfier? :P

@DJMcMayhem took me a bit

Jan Dvorak

Puns are the lowest form of humor. Especially if they involve the Mariana trench.

mbomb007

What is ☺ squared?

flawr

I'm waiting for the how many bytes does it take to screw in a lightbulb kind of jokes.

Riker

lel

DJMcMayhem

@flawr nineteen

Riker

8:24 PM

no the 19th byte will never screw it in

they'll just keep joking about it until somebody butterfingers the bulb and it shatters

flawr

...it will only screw up...

DJMcMayhem

@Riker Oh. Then 20?

Basic Sunset

I'm sure Mathematica has a built-in

Jan Dvorak

You can't change a lightbulb, but you can still punish them for what they are.

Doorknob

Oh, did you hear about the mathematician who chose his u and dv wrong? Yeah, he was humiLIATEd.

flawr

8:25 PM

explanation-request

Riker

@flawr ;-;

DJMcMayhem

@BasicSunset Either way, jelly will probably beat it.

Riker

@flawr LIATE method

Doorknob

@flawr We were taught Log / Inverse trig / Algebraic / Trig / Exponential as a rule of thumb for integration by parts. Came up with that one during class :P

Riker

I don't know calc and even I've heard that :P

AdmBorkBork

8:27 PM

@Doorknob ! moarpowah.com/wp-content/uploads/2012/10/Meme-TRAVIS-1.jpg

flawr

@Doorknob So what does this rule say?

Doorknob

@flawr The first on the list becomes u, and the other part is dv.

DJMcMayhem

My favorite math mnemonic is singing the quadratic formula to the tune of pop goes the weasel

Riker

@AdmBorkBork no space between ! and link

@DJMcMayhem that sounds hilarious

Jan Dvorak

Ah. The devil is in the DETAILs.

AdmBorkBork

8:28 PM

@Riker What's it matter? I didn't want it to onebox, and that accomplished the same thing.

Riker

ah, I thought you did want it to onebox

AdmBorkBork

If I did want it to onebox, I would've not had a bang

DJMcMayhem

> X equals negative B, plus or minus square root, B squared minus 4 AC --- All over 2A!

Riker

10/10

DJMcMayhem

bows

Downgoat

8:29 PM

@Riker FYI: I've removed you from GitGoat's collaborators, because it now contains (kinda) personal data, and now I'm able to distribute beta builds in a much nicer way anyway

Jan Dvorak

Just derive the quadratic formula yourself once, and you'll remember it forever

Riker

@Downgoat it's cool, I don't mind

AdmBorkBork

@flawr @HelkaHomba It's also way easier to add a bit more water than to add a bit more mixture, so go slow on adding the water.

@Riker Oh, I see what you meant. No, I stuck a character in front so it wouldn't onebox. Happened to be a bang. Hah.

Didn't even realize.

flawr

@Doorknob hm that actually sounds useful. I was never good at integration.

Riker

@AdmBorkBork ah lol

btw, would somebody who lives with that northeast blizzard mind mailing snow to so-cal? weather is not good here

it's 93°F outside

DJMcMayhem

8:37 PM

93° in March? O_o that rarely happens in June here

fergusq

I was down-voted. Why was I down-voted? Why does that usually happen?

Riker

because somebody doesn't like your answer or question

Kritixi Lithos

Or an accident when scrolling in mobile

fergusq

Probably I should not care, but still, I could always try to improve my answers. It's sad that down-voters don't explain their intentions.

Anonymous

@fergusq People usually don't explain downvotes because leaving explanations usually leads to flaming.

Downgoat

8:42 PM

I mean if you include how to improve and what specifically is wrong I haven't had any problems with people getting mad

Riker

sometimes OP disagrees that's wrong tho

Downgoat

though, if they are a new user it's about useless to downvote without an explanation

Anonymous

@Downgoat When the user disagrees about the presence of a problem, it often turns into an unpleasant argument (especially with newer users).

Jan Dvorak

@Riker These are always fun. I mean, if you're evil towards the evil side, you count as a good guy, right?

Anonymous

Like I've said many times before: it's best to not worry too much about downvotes. Just make better posts in the future.

Downgoat

8:45 PM

@Mego Usually in that case I 1) be clear that my vote was based on opinion 2) be specific and cite meta so there's basically 0 room for dispute

If they argue with you, you are also not obliged to respond

anyway, the reason I am so strong for commenting on downvotes, is if you don't comment there is 1) 0 improvement as a result 2) basically only results in you/PPCG coming off as hostile

AdmBorkBork

@Mego Take that! This response counts as an explanation, therefore my reply here counts as a flame.

Riker

@flawr huh apparently math uses german for terms sometimes, like "eigenvalues"

flawr

@Riker Yep =)

Riker

ya

and that means "self" right

flawr

There is also the nullstellensatz

or ansatz

Riker

8:56 PM

oh cool

also @Downgoat did apple approve app without you sending it >_>

or did you resend the app to them

Downgoat

resent

Riker

@Downgoat ah k

fergusq

Some people use Nullstellensatz in Finnish too, although the correct Finnish translation would be nollakohtalause.

It's weird.

Riker

you're finnish?

fergusq

Yes

flawr

8:58 PM

@fergusq I'm gonna use nollakohtalause form now on :D

Riker

@fergusq are you aware some people don't believe finland exists

fergusq

It's a direct translation, because Nullstellen is nollakohta in Finnish and Satz is lause. Btw what is the English term for Nullstellen? I'm not sure about it.

flawr

@fergusq usually roots or zeros

fergusq

@Riker No D: Finland exists very much for me.

Maybe they use Nullstellensatz in English because Root theorem is ambiguous.

Riker

@fergusq lol

en.reddit.com/r/finlandConspiracy <- what I'm referring to

fergusq

9:13 PM

@Riker That sounds like it's invented by a Finnish person. "no country in the world can possibly be that good." ??? In reality Finnish people have low national self-esteem and always think that Sweden is better and Norway is richer blah blah blah. Every time someone mentions Finland outside Finland we think: "Oh god someone knows that we exist."

Jan Dvorak

But ... they invented heavy metal

Riker

@fergusq lol

DJMcMayhem

Ehh, not really. That was mostly the UK and US.

But death metal is from thereabouts iirc

Riker

TIL SO docs has audits

ATaco

Yeah but you could live in Australia, known for bad internet and lethal fauna.

Riker

9:16 PM

@ATaco I'll never forget that wombats can take down cars

Jan Dvorak

Don't forget the drop bears

Riker

lol

fergusq

You see: Finnish bands just copy others. Take a band, for example Hanoi Rocks. And there it is: copying Guns'N'Roses etc etc.

DJMcMayhem

@fergusq Not sure if serious...

It says they're 6 years older than G&R

fergusq

I am just demonstrating Finnish mentality. (=not serious)

Downgoat

9:19 PM

@ATaco australia is also known for accidentally running seasons.reverse()

Jan Dvorak

A duplicate older than its original? StackExchange is pretty familiar with the concept.

quartata

@Riker I swear, no matter how hard I try, I've never gotten a review audit

Downgoat

@fergusq still better than American mentality :P

3

DJMcMayhem

@Downgoat That's amazing

Riker

@quartata huh

Григорий Перельман

9:27 PM

@Downgoat I am glad that is a thing that exists, I can die in peace now.

Jan Dvorak

Bam. French cheese is now illegal because ... it contains ... bacteria. And bacteria kill people. Also, let's allow guns for everyone. Shall we?

Григорий Перельман

"Banning guns" is now illegal.

Downgoat

@JanDvorak let's also allow shooting people because people host viruses and viruses hurt people

Jan Dvorak

Banning guns kills people

Also, pizza is now a fruit

Downgoat

@JanDvorak I think congress voted for pizza to be considered a vegetable a couple years ago already

I am not joking

Григорий Перельман

9:33 PM

They did. It's great.

Jan Dvorak

The cheese ban is also a real thing

Григорий Перельман

Also, according to the Supreme Court of the U.S., tomatoes are vegetables, not fruit.

Downgoat

Help, our government need help

Lembik

hi

Jan Dvorak

Knowledge is knowing that tomatoes are fruits. Intelligence is knowing not to put them in a fruit salad.

2

Downgoat

9:35 PM

@JanDvorak can I make this life motto

Anonymous

@JanDvorak I've usually heard that as INT vs WIS

Jan Dvorak

But which one is which?

DJMcMayhem

@Mego Wait, are you a D&D nerd?

Anonymous

@DJMcMayhem What made you think I wasn't?

DJMcMayhem

Idk, I've never heard you mention it before

Anonymous

9:39 PM

@JanDvorak INT is the useless knowledge, WIS is the knowledge that keeps you from doing stupid stuff

DJMcMayhem

I just recently started playing

Григорий Перельман

WIS is common sense.

That's basically the easiest way to think about it.

ATaco

Yeah but INT may be the difference between using a poisonous mushroom and an edible one

Григорий Перельман

WIS will have made sure you're not in a situation where you need to eat an unknown mushroom to survive in the first place.

Jan Dvorak

Every mushroom is edible. Some are only edible once.

14

ATaco

9:40 PM

Although WIS will probably suggest you don't eat the mushroom anyway

And CHA will get someone else to eat the mushroom first

CON will make whether the mushroom was poison or not irrelevant

DJMcMayhem

What does DEX do?

ATaco

Nothing that I can relate to poisonous mushrooms

Jan Dvorak

DEX lets you pick it up without the foot

ATaco

STR will let you pick the biggest mushroom

Jan Dvorak

STR lets you pick up mushrooms by uprooting trees they are attached to

Mendeleev

9:46 PM

You've goat to be kidding me

Anonymous

DEX lets you throw the mushroom into your enemy's open mouth

Jan Dvorak

CON lets you eat the mushroom without as much as contracting diarrhea

Mendeleev

Downgoat

@Mendeleev on the iOS app, can you open a repo, and go to the "Pull Request" tab and see if that crashes?

Mendeleev

one sec

Downgoat

10:08 PM

@JanDvorak edible =/= eatable

Lembik

still no answer :( Maybe tomorrow!

ATaco

On which question? Perhaps I can tackle it.

Destructible Lemon

> People need fruits to be healthy. Hey lets make pizza a fruit so people can be healthy

Them probably

betseg

7

Riker

@Downgoat "being sheep is now illegal"

Jan Dvorak

10:22 PM

@betseg well... false

Downgoat

@Riker :( now I am sad that this is not real law

Riker

lol

RIP

betseg

@JanDvorak What is false

Riker

> German auctioneer Breker has told the Apple obsessive site MacRumors that it will be auctioning off one of the eight functioning Apple-1 computers remaining in the world. The buyer will get a couple bonus features as well: original manual and documentation, the receipt for the motherboard and cassette recorder, and a record of telephone conversations with Steve Jobs and Wozniak.

source

Adám

@Downgoat Prohibiting is now illegal.

ATaco

10:25 PM

Esoteric programming language

An esoteric programming language (sometimes shortened to esolang) is a programming language designed to test the boundaries of computer programming language design, as a proof of concept, as software art, as a hacking interface to another language (particularly functional programming or procedural programming languages), or as a joke. The use of esoteric distinguishes these languages from programming languages that working developers use to write software. Usually, an esolang's creators do not intend the language to be used for mainstream programming, although some esoteric features, such a...

Destructible Lemon

@JanDvorak I agree: you have to carve the rock specially so that lightning can constantly pass through it. except when you don't want it to

ATaco

The exact layout of the carvings isn't part of the scope of this explanation of CPUs.

Destructible Lemon

yes, of course

which is why I don't go into how you carve it

Jan Dvorak

If CPUs are just rocks that were taught to think, then humans are just rocks that were taught to multiply, then how to think. Although, I guess that would explain something...

betseg

Humans are just a bunch of atoms studying atoms.

Destructible Lemon

10:30 PM

@JanDvorak no. humans are water bottles taught to multiply and then taught to think

Downgoat

@betseg this is like saying neutron star is gravity tricked into not working

Destructible Lemon

@Downgoat intriguing hypothesis

Jan Dvorak

@DestructibleLemon remember: commas are important.

Destructible Lemon

you understood what I was saying

Mendeleev

this conversation with no context...

betseg

10:31 PM

@JanDvorak help a thief!

Destructible Lemon

@Mendeleev is about the same as with context

ETHproductions

@JanDvorak No commas really are necessary

Destructible Lemon

also, just remember we can never let this die

23 hours ago, by Mego

Tabs aren't that bad. They're just another form of whitespace.

ETHproductions

prays joke wasn't too subtle

Destructible Lemon

from context it is clear you mean no commas are necessary

which is false

Riker

10:34 PM

@ETHproductions I got it :P

wasn't really a joke tho

jsut 2 possible interpretetations

betseg

Destructible Lemon

well, the second one is paradoxical; no implies disagreement, then he says the same thing

ATaco

I find the Oxford Comma very important in lists.

ETHproductions

Well "no commas really aren't necessary" doesn't have much room for interpretation, with or without context

aditsu

hey, is there an easy way to find out why a string didn't match a regex?

ATaco

10:36 PM

What's the string and what's the Regex?

aditsu

the regex is pretty long..

ATaco

Good luck.

Riker

@aditsu you can always try regex101 iirc

ASCII-only

@aditsu This is PPCG though

Riker

may break it down

ASCII-only

10:36 PM

TNB > regex101

Jan Dvorak

Either you break down the regex, or you break down from the regex.

aditsu

@Riker thanks I'll try

ASCII-only

@aditsu As long as it doesn't use a million different types of lookaheads/lookbehinds it shouldn't be hard to understand

Riker

@aditsu because I'm curious, can you pastebin the regex?

aditsu

well, I understand it, and I think it's clear the string matches :p yet it does not

Riker

10:38 PM

ah

Jan Dvorak

Ah, the "denial" stage

ETHproductions

Still, multiple sets of eyes are better than one

ASCII-only

@ETHproductions :O you have multiple sets of eyes?

Jan Dvorak

////(::::)\

Григорий Перельман

CMC: Given two ints, output a random non-transparent image with those dimensions. Every possible image should have equal chance of being generated.

aditsu

10:39 PM

@Riker hmm, it doesn't seem to like java flavor, but may be fixable with an escape

ATaco

Random hurts me so.

ASCII-only

@ГригорийПерельман easy, just do a bitmap from /dev/random

Riker

@aditsu hm

Григорий Перельман

@ASCII-only That's why it's a CMC

Also, you might be able to do better than that

aditsu

@Riker I'm hesitating, because 1) it is kinda horrifying and 2) it will reveal what I'm working on

Riker

10:41 PM

ah

don't worry if you don't want to share, no harm done

ASCII-only

horrifying -> sounds like an email regex

aditsu

I'll reveal what the problem was if I figure it out

Riker

hm ok

ATaco

It may be the time when Regex isn't the solution.

Jan Dvorak

->x,y{"P3 #x #y 255"+(1..3*x*y).map{rand 256}.join(" ")}

aditsu

10:43 PM

@Riker I got it to accept the syntax, but then it just says "Your regular expression does not match the subject string."

ASCII-only

wait it was a url regex

Riker

@aditsu hm

normally for me it breaks it down

aditsu

it explains the regex, but says nothing about where the match failed

Riker

hm, that's not the site I was thinking of apparently

not sure which one I am

aditsu

ooh, it has a "regex debugger"

ASCII-only

10:45 PM

@aditsu Then I'd either change the test string or simplify the regex until it matches and work from there

Or just use the debugger

aditsu

it has huge mountains of output, but seems helpful

Riker

how long is this regex

are we talking 30 chars, 100 chars, 68k chars, what?

aditsu

278 chars, it's built from several smaller ones

ASCII-only

@aditsu I'd just look at every match it accepts and the last one where it fails

Riker

@aditsu ah

I was close ;P

ASCII-only

10:47 PM

Make sure it's matching what you want it to match

aditsu

I'm starting to see where the problem is

oops, it's not that

Riker

rip

Downgoat

btw @Riker on the GitGoat app from TestFlight, can you try opening a repo and going to Pull Requests tap?

Riker

yes, but not atm

will do soonish tho

aditsu

I'll try to simplify it until it matches..

ASCII-only

10:55 PM

> tap

what is this, Homebrew?

ATaco

@Downgoat Crashes my app

ASCII-only

@aditsu Maybe you could test one part at a time if it's possible, since you said it's made of multiple smaller ones?

aditsu

I'm replacing some small parts with the corresponding parts of the string :)

New Main Posts

0

Q: λ-calculus to js arrow notation transpiler

Not an interpreter. Arguably a compiler. But I'm talking about a transpiler. It can be in any language, but it must return js-valid arrow notation code. The λ-calculus string would be passed as an argument to a function, or the whole program, and in some way the program would return/log/print t...

aditsu

the instant evaluation is really helpful

oh jeez, a trailing newline is messing it up, gotta start over

ok, now it matches.. and I think the real problem is I had a trailing space ><

I noticed it earlier and deleted it but it still had the newline

(my original code doesn't have the newline but has the space)

Downgoat

11:02 PM

@ATaco ok, yeah, so it isn't working :(

aditsu

ok, on to the next bug..

Conor O'Brien

11:33 PM

CMC: given N, compute 10^N without any 1s or 0s in the source code

Helka Homba

print (8+2)**input()

Conor O'Brien

TypeError: unsupported operand type(s) for ** or pow(): 'NoneType' and 'str'

:p

Helka Homba

Python 2

Conor O'Brien

ik, thus the :p

Anonymous

@ConorO'Brien Actually, 1 byte: ╤

Helka Homba

11:38 PM

Python 2 and 3 need to stop the confusion and get back together

Conor O'Brien

Python 2.5, then?

Helka Homba

Python 2 + Python 3 = Pypythonthon 5

Destructible Lemon

@HelkaHomba no that would be 5Python

or Python 5, however you want to represent the multiplication

x*y+x*z = x*(y+z)

Conor O'Brien

where did multiplication come from

Destructible Lemon

Implicit multiplication

I could also represent that equation as xy+xz = (y+z)x

Helka Homba

11:46 PM

CMC: Write a complete sentence using only programming language names and at most one of each of the words {a, I, at, is, it, the, of, me, you}. [pop-con]

e.g. "Seriously, the ruby is actually a perl!"

Anonymous

@HelkaHomba "I fish."

Anonymous

2 languages, 7 bytes

Helka Homba

@Mego You python?

Anonymous

Verbing a noun doesn't count

Helka Homba

You penguin?

Conor O'Brien