The Nineteenth Byte

lyxal

12:00 AM

@thejonymyster JavaScript + infinity + epsilon when? :p

3

emanresu A

@RadvylfPrograms FYI, the Vyxal Bot is doing a law degree to convict you for crimes against programming languages.

Radvylf Programs

i can;t go back to jail

5

lyxal

12:15 AM

@RadvylfPrograms how many fonts will I need to install to use it?

Radvylf Programs

It comes with a font that uses ligatures to turn every program into a single character. Its name is Timy. We like timmy.

Bubbler

@emanresuA no, arrays can't form cycles in K

Radvylf Programs

(Not really)

user

12:38 AM

@RadvylfPrograms You don't really like Timmy? :(

@RadvylfPrograms +50i rep to anyone who does this in Haskell

emanresu A

Imaginary rep?

user

Shhhh

emanresu A

I feel like this isn't the first itme

... nvm?

Bubbler

1:18 AM

@user Haskell, 24 bytes: data T=T[T];a=T[T[T[a]]]

though it interprets the task using the internal representation, not the built-in equality operator

T can derive Eq, but a==a is an infinite loop

thejonymyster

@Bubbler where is input

Bubbler

For arbitrary n, 41 bytes: data T=T[T];f n=iterate(\x->T[x])(f n)!!n

@thejonymyster just noticed that I read only half of the problem lol

thejonymyster

:P ok thats understandable lol

Unrelated String

3:54 AM

@Bubbler golf \x->T[x] to T .pure?

Bubbler

seems to work, yeah

emanresu A

Do you even need the space?

And if so, could someone explain to me why?

thejonymyster

4:12 AM

well heres the error if you dont

Loaded package environment from /opt/ghc_env
[1 of 1] Compiling Main             ( /ATO/code.hs, /ATO/code.o )

/ATO/code.hs:1:25: error:
    Not in scope: ‘T.pure’
    No module named ‘T’ is imported.
  |
1 | data T=T[T];f n=iterate(T.pure)(f n)!!n
  |                         ^^^^^^
yargs: execvp: No such file or directory

if that offers any insight

emanresu A

CMC: Given an array of dice (integer arrays), return the ratios of how likely each is to win

(if there's a tie, it counts towards all winners)

Bubbler

example?

emanresu A

Damnit I just realised it's impossiible to deal with ties, nvm

Bubbler

with [1, 2, 2, 3] wouldn't the answer be [1/4, 3/4, 3/4, 4/4]?

emanresu A

¯\_(ツ)_/¯ Never mind

user

7:56 AM

@emanresuA i think without the space it thinks T is some module and the pure function is inside that. If it were lowercase it wouldn’t be a problem (but constructors can’t be lowercase)

@Bubbler nice, I’m so impressid I’ll five you 500i rep

It doesn’t use the same object in memory though right?

lyxal

8:28 AM

@user fiverr but code golf

mousetail

8:54 AM

@lyxal Only programs under five bytes accepted

emanresu A

9:04 AM

In theory it might be possible in older versions of Vyxal

Where lists were mutable

Adám

9:37 AM

Can the PCRE regex [A-Z_a-zÀ-ÖØ-Ýßà-öø-üþ∆⍙Ⓐ-Ⓩ][\wÀ-ÖØ-Ýßà-öø-üþ∆⍙Ⓐ-Ⓩ]* be golfed further?

Sandbox Posts

0

A: Sandbox for Proposed Challenges

Quantise a list code-golf array In music production, quantisation is the process of "aligning" recorded notes to the beat, to remove the variability caused by imprecise human playing. In this challenge, we will implement an abstract and approximate version of quantisation, representing notes as r...

0

A: Sandbox for Proposed Challenges

The least amount a steps a chess pice can reach a position I have previously posted a challange: smallest number of steps for a knight in chess. Now I would like to go a stap further by adding the possibility to choose you pice. If you place a pice on any square of a chessboard, what is the small...

pxeger

10:30 AM

→ 1 message moved to The Nineteenth Bakery

Neil

11:40 AM

@Adám (?!\d)[\wÀ-ÖØ-Ýßà-öø-üþ∆⍙Ⓐ-Ⓩ]+ ?

Adám

@Neil No, that includes the - in -hello

Neil

12:04 PM

@Adám Try it online! or am I missing something?

Wezl'

@RadvylfPrograms im loving the colons. colons are the best

Number Basher

CMQ: should we create a lyal for common languages like vyxal? cuz i missed out on the vyxal lyal and want it to be done... or make old langs back again for lyal

thejonymyster

@Bubbler each die is itself an array of integers

thejonymyster

12:58 PM

@emanresuA how would it not be possible to deal with?

@thejonymyster (or at least i reckon thatd make more sense lol but i guess it could be just n-sided dice)

Number Basher

1:10 PM

Let's unstar this , this is from a week ago

Aug 24 at 12:04, by Ginger

Welcome to the sixth Language Design Workshop! The general premise is that you can post work you've done or are doing on esolangs and people will give feedback. In short, you'll get to show off our languages and their features, chat about them, get feedback, try out WIP languages, and, hopefully get ideas over the next 24 hours.

Oh wait we cant

nvm

thejonymyster

CMC: given a positive integer N, output the list of positive integers <=N such that there are an even number of distinct ways to represent each integer M as a sum of only elements of the list <M (with duplicates allowed)

Radvylf Programs

@NumberBasher But I can :p

thejonymyster

@thejonymyster example: for N=1, output 1 since 1 has 0 (even number) ways to be written as the sum of [] (there are no positive integers in the list less than 1), for N=2, still only output 1 since 2 can be written as 1+1, (1 being a member of the list), so that's 1 way to write it (odd number) so 2 isnt included

lyxal

@NumberBasher why though? It would have fallen off the starboard naturally

Number Basher

@RadvylfPrograms hmm...

thejonymyster

1:21 PM

i certainly dont see it on the starboard

Number Basher

@lyxal it STILL hasn't minutes before

Radvylf Programs

I think usually we remove time specific stuff like that just to not clutter things up

thejonymyster

oh did it just get removed :P

lyxal

@RadvylfPrograms we usually unpin, we don't remove all stars though

Number Basher

@RadvylfPrograms and not to mislead people esp. since its nearly wednesday

lyxal

1:21 PM

it's just that the starring frequency of messages has been low lately

5

Number Basher

@lyxal remove from starboard?

Radvylf Programs

@lyxal yeah that's a good point

lyxal

@NumberBasher you can either unpin or remove all stars

Radvylf Programs

Not too long ago it would've been pushed off naturally within like, 24 hours

Number Basher

true

Radvylf Programs

1:23 PM

There is some precedence for star-clearing when star frequency is low

lyxal

the lower starring rates are probably due to the lower rates of off-topicness

because there isn't as much starbait anymore

2

which is really a shame given that's what I've been practicing for the last 2 years :p

thejonymyster

i love saying things are <x> bait. i see some weirdly complex keymash and i call it esolang bait

3

Number Basher

@lyxal this feels like starbait

mousetail

What have you been practicing? producing starbait?

thejonymyster

theres a fine line between "this is obviously star bait" and "i saw the word star so i starred it"

lyxal

1:24 PM

As funny/meta starring messages about stars is, you don't need to star two messages on starring things :p

2

@mousetail yes

I know I'd tailor a lot of messages for maximum stars back when off-topic was prevalent

mousetail

Yea I'll pesonally Sun any incorrectly starred messages

Radvylf Programs

I almost feel like we should allow slightly more off-topic discussion here, it's getting a little boring discussing Code Golf 24/7 :p

Number Basher

@lyxal it is now 4 lol

@RadvylfPrograms true

mousetail

@RadvylfPrograms Yea, need to keep the balance

thejonymyster

@RadvylfPrograms we gotta learn to surf both off topic and on topic together

New Posts

1:26 PM

0

Q: Solving an easy Sudoku in increasing digit order

Introduction: I'm old-fashioned and still read a physical newspaper in the morning while eating my breakfast. Although I don't like Sudoku that much, I do solve the Light-complexity ones, which are extremely easy. With these, I always try to solve all the numbers using only Hidden Single (with a ...

thejonymyster

oh woah that got posted

Number Basher

that was... unexpected

thejonymyster

godspeed i hope it turns out to be interesting lol

Number Basher

hi @UnrelatedString

lyxal

@thejonymyster it seems that those are strongly intercoupled - the off-topic room doesn't get much attention either, because not many people are checking it specifically for off topic stuff

2

honestly, I don't think the levels of off-topicness were too bad actually

Like sure there'd be a few conversations occasionally that needed moving

but probably not that many to warrant a new room

Number Basher

1:28 PM

i actually think offtopicness is ok for tnb

unless it is like spam or clutter or 1000 messages of the same topic

mousetail

But not too much off topicness

Radvylf Programs

Some off-topic is fun discussions of off-topic stuff, like the peanut butter discussions. I like those. But quite often the off-topic discussion was streams of thought, clear and unfunny starbait, or TNBlogging that's not really relevant to anyone else

thejonymyster

i draw the line personally at "am i about to start a conversation that isnt on topic" and if so i post it here

2

Radvylf Programs

@RadvylfPrograms (And I am guilty of all three of those :p)

thejonymyster

we need a tnb tumblr that we all have access to

Radvylf Programs

1:29 PM

@NumberBasher Long discussions on a single off-topic topic are better than short, pointless bits of clutter IMO

thejonymyster

so we can microblog at eachother

mousetail

@thejonymyster We need a TNB twitter where all messages are limited to 19 bytes

9

Radvylf Programs

higuysiamgolftoday!

thejonymyster

(o_o)/ {hi twitter)

Radvylf Programs

Should I make a userscript for this

thejonymyster

1:31 PM

lol a userscript for what exactly

lyxal

help, bees are back

Number Basher

@RadvylfPrograms which is why it said clutter or ...

Radvylf Programs

I can stop working on Twitch for a few hours and implement TNBwitter

It would use a chat room as the back-end, like CoC

thejonymyster

i mean counting to 19 isnt so hard

Radvylf Programs

Well yeah but that's boring

Having a feed and following and stuff is cool

thejonymyster

1:32 PM

oh i see what you mean

lyxal

@thejonymyster you're right. Counting to 3 is the hard part!

thejonymyster

interesting

@lyxal thats why i just do three lots of five and then... oh wait

also haha funny gaben

lyxal

thank you thank you I'll be here all week :p

Number Basher

hhh

thejonymyster

i feel like someones trying to sell me something

mousetail

1:39 PM

Challenge idea: English x Your lang polyglot. Your program must also pass some grammar checker with no warnings but also do something useful in your programing language.

thejonymyster

that's always fun to think about

langs with arbitrary tokens pass for cheap (except maybe incident good luck lol), 2d langs might have some advantages as well, not sure what else works

langs with single char commands also have a similar advantage to 2d langs but without the ability to control flow away from difficult stuff easily

mousetail

According to this quillbot.com/grammar-check print("hello world") is perfectly valid english

thejonymyster

*Print

thats messed up that they dont check for capitalization

actually what is that site

i typed print m sala just testing to see what would mess it up, and it offered to fix it

and it turned it into m sala print

now its not complaining

m sala w e print andg => print andg m sala w e print andg

lyxal

:thonk:

:thonk: :thonk:

thejonymyster

sorry i didnt realize but that trailing space is significant

Number Basher

1:45 PM

SunSIp i good at this I hope

is

github.com/TvoozMagnificent/SunSip

mousetail

Inform 7 would be great

Need more golfs in inform 7

lyxal

Hmm yes

excellent paraphrasing

mousetail

@lyxal Imagine if it actually managed to create shorter equivalent code

lyxal

og answer I used btw

Number Basher

apparently I can't get to that website but check this

set the last variable to "Hello, World!"

and now

out

whoops forgot to shift return

mousetail

1:48 PM

@NumberBasher Wouldn't work, inconsistent capitalization

thejonymyster

Looks like what we've learned is that computers are not very good at checking grammar

Number Basher

screw it

change "Hello, World" to "hello, world" lol

mousetail

At least that one site is terrible

lyxal

@thejonymyster neither am I sometimes. Guess that makes me a computer too. Beep boop or something.

mousetail

Aren't we, just like computers, rocks tricked into thinking?

lyxal

1:50 PM

they're minerals! goodness mousetail.

Adám

@Neil My bad. Going back in my log, I see that it was perfectly correct all along. Thanks.

mousetail

grammarcheck.net/editor This site suggests print(" hello world") for some reason

... I don't see how this improves the grammar at all

Number Basher

maybe it wants spacing

mousetail

Spacing should come before the ( no?

not after the quote

Number Basher

grammarly is better

mousetail

1:51 PM

I wouldn't require a comercial product for a challenge

Number Basher

its not neeccesarily commercial

set the last variable to "Hello, World!"
and now
out

gives

Grammarly ran hundreds of checks on your text and found no writing issues.
Check back in when you’re ready to write some more.

thejonymyster

tbh i feel like it might be more reasonable to just.. write up a grammar

2

Hmm nice

for the challenge

@thejonymyster True

1:53 PM

lol

mousetail

Actually I don't think the challenge works anymore

thejonymyster

1. for internal consistency
2. so people arent at the whims of the ever fickle machine

mousetail

Any rules would feel too arbirary

thejonymyster

No, base it on english

but just like... very simple english

PyGamer0

@RadvylfPrograms uh CoC got frozen lol

Number Basher

1:54 PM

why lol lol

thejonymyster

~~allow people to add to the grammar if they can justify it~~

lyxal

@NumberBasher it was forced to be frozen because it was breaking chat rules or something like that

in Chat-on-Chat, Jun 21 at 23:31, by Cesar M

It looks like this room has been primarily used to have encrypted conversations that regular folks can't have access to without installing a user script. Private messaging is not a service we offer on the platform. While anyone could technically check the content of yalls message by installing the user script, we don't want to have users needing to install a script to be able to participate (or read) in a chatroom.

mousetail

Maybe I should make it caveman english. Subject Verb Direct Object. No conjugation

thejonymyster

see there you go

hm, you might need a dictionary unfortunately

"which words are verbs"

mousetail

Yea

thejonymyster

1:56 PM

this sucks i want funny grammar challenge

Number Basher

is "can" a verb or what

mousetail

There are word lists available on github, including data about their role

@NumberBasher Both

Can can can? Is a valid sentence

Number Basher

as in the "can" in "Can a canner can a can like some canners can can a can?"

don't ask me which

thejonymyster

~~what about buffalo~~

Number Basher

"James while John had had had had had had had had had had had a better effect on the teacher"

thejonymyster

1:58 PM

~~wikipedia show me the forbidden sentences~~

Number Basher

i.e. James, while John had had "had", had had "had had"; "had had" had had a better effect on the teacher. (obviously)

thejonymyster

@mousetail aight i guess that could work

still a bit depressing :')

Number Basher

Someone in our class named harry was unfortunate enough to learn in grammar class what his name meant

haha:

> *Cao ni ma - 草泥馬; cǎonímǎ, "a horse made from mud and grass"/"mud-grass horse" for 肏你媽; cào nǐ mā, "fuck your mother", used in mainland China similarly to "fuck you" in English.

thejonymyster

@mousetail alternatively: have the solver invent their own grammar, and score them on said grammar :P

Number Basher

my grammar checking function:

mousetail

2:05 PM

@thejonymyster Interesting, but how to objectively score the grammar?

Number Basher

lambda:1

New math post! https://medium.com/@NumberBasher/pact-year-round-program-series-1-the-stable-matching-problem-9064711a81e1

thejonymyster

@mousetail Simple! You just (mumble mumble grumble something something...)

2

mousetail

Ah yes, all clear now thanks. Great suggestion

Btw it's funny how half the starred messages are from the last hour now

thejonymyster

that's how it's alwlays been

Number Basher

@mousetail you sure?

only half?

mousetail

2:11 PM

Well the ones that are actually useless and only you starred will soon be gone at least

thejonymyster

quick make 10 alts and star the messages to prove your point ( do not do this)

mousetail

Get banned from TNB Any%

user

@mousetail MORNING MOTHERF*CKERS

Radvylf Programs

Been there, done that:

Nov 30, 2021 at 14:32, by Redwolf Programs

MORNING MOTHERFUCKERS

Number Basher

@mousetail true

user

2:14 PM

@RadvylfPrograms Hmm, that seems to be by someone named Redwolf. I thought he had no relation to you?

lyxal

@RadvylfPrograms been there, done that:

Jun 19, 2021 at 2:02, by Redwolf Programs

Apr 27 at 12:58, by Redwolf Programs

Redwolf: Good morning.
Lyxal: Good morning.
Razetime: Good morning.
caird: You all sound like robots, try spicing it up a bit.
user: MORNING MOTHERF*****S

Radvylf Programs

@user Oh...um...he's my...long lost twin?

We share a brain though

lyxal

as you can see, your honour, it is 100% canonical and in-character for my client (user) to say "MORNING MOTHERF*CKERS"

Radvylf Programs

That was back in the hivemind era

mousetail

You all still feel like a hivemind

Number Basher

2:15 PM

lol

lyxal

@mousetail only on Wednesdays though. Never on Mondays and definitely not on Fridays

Thursdays are a maybe

user

@lyxal I really appreciate the pro bono work you do bro

lyxal

better call lyxal!

3

user

@mousetail You mean we all have the same opinions? Because TNB certainly feels like several distinct individuals (and some socks) to me

lyxal

@lyxal "hi I'm lyxal gaming. Did you know that you can golf your programs? The spirit of this site says you do, and so do I. I believe until proven shortest, every answer on this site can be golfed. And that's why I fight for you TNB!"

user

2:20 PM

@RadvylfPrograms That's what Off-Topic TNB is for. It's wild in there

Number Basher

bye

thejonymyster

2:35 PM

@thejonymyster js, ## bytes: spoiler

New Posts

3:07 PM

1

Q: Polyglot Quiz (Cops' thread)

This is the cops' thread of a cops-and-robbers challenge. The robbers' thread can be found here In this challenge as a cop you will choose two programming languages A and B, as well as a non-empty string S. You are then going to write 4 programs: A program which outputs exactly S when run in bo...

code-golf cops-and-robbers polyglot

1

Q: Polyglot Quiz (Robber's thread)

This is a robbers; thread. For the main rules to this challenge see the cops' thread In this challenge robbers will choose a cop's vulnerable or safe post and try to figure out a pair of languages such that they print the correct results for the 4 programs. When you find a solution post an answe...

cops-and-robbers polyglot

thejonymyster

yay :D

mousetail

3:19 PM

Interesting

Cops and robbers posts are OP for rep since you get double points

Radvylf Programs

3:32 PM

Well, more liek 1.5×

Since the Robbers post usually gets fewer

thejonymyster

my first real cnr submission, hopefully not illegal

DLosc

4:05 PM

@RadvylfPrograms Python 2, 62 bytes: def f(n):a=[];x=[a];exec"x=[[x[0]]]+x;"*~-n;a+=[x[0]];return a

Also TIL that the exec trick doesn't work in Python 3.

@mousetail This sounds interes

mousetail

I see what you did there

Wezl'

4:34 PM

GolfngStrtgsForText

Adam

5:24 PM

@DLosc I mean, it's technically possible, but it almost never saves bytes; e.g. def f(n):exec("x+=[[x[-1]]];"*~-n,d:={'x':[a:=[]]});a+=[d['x'][-1]];return a

DLosc

Right, you have to pass an extra argument.

Adam

5:43 PM

Anyways, I spent too much time thinking on this...

Python 3, 60 bytes: def f(n,a=[]):g=lambda m:m and[g(~-m)]or a;a+=g(n);return(a)

Radvylf Programs

I'm thinking about making a blog

thejonymyster

please do

Adám

6:07 PM

@RadvylfPrograms The Red Howl?

mousetail

@RadvylfPrograms If you do try to cover less than half the screen with adds

thejonymyster

6:35 PM

CMQ: if X implies (X implies Y), does X imply Y?

im trying to approach it formally but i dont have the background for it :P

Adam

I don't think so?

If you don't know how to decompose the expressions, you could just go through all 4 of the cases and see if they match

Wheat Wizard

@RadvylfPrograms Even less since I rep-capped from another post :P

thejonymyster

I guess it's just confusing because I can clearly reason that if (x->(x->y)), and you have x, theres no way not to get y

but if you dont have x, x might not imply y, but that seems vacuous :P

Wheat Wizard

@thejonymyster Yes.

proof

pxeger

6:56 PM

Using the Haskell type system as a proof assisstant under the Curry-Howard correspondence is a weird flex but ok

thejonymyster

lmao

yeah im not gonna act like i understand it but sure :P

pxeger

by "weird flex" what I really mean is "very cool hack"

thejonymyster

my only other crack at why is "if x, then the statement holds easily, if ~x, you can get x->y for free via principle of explosion"

pxeger

that's valid

Wheat Wizard

Here's a proof in an actual theorem prover

thejonymyster

6:59 PM

@pxeger i may be a little bit chronically online, i read that initially as emotional validation

pxeger

you're valid ♥

oh wait no you're a tumblr user

thejonymyster

tragically

@WheatWizard not to bug you for a million years, but can i ask what the "f g x = g x x" is?

explain as technically or looseley as you want

pxeger

Under the Curry-Howard correspondence, iff you can instantiate a type, then the equivalent of that type as a mathematical statement must be true

So f g x = g x x is just some valid function with the type f :: (x -> (x -> y)) -> (x -> y)

thejonymyster

thank u :-)

pxeger

and the fact it exists means (x => (x => y)) => (x => y) must be true

Wheat Wizard

7:02 PM

Yes.

Note that the other way around is not necessarily true though. Haskell's type system is constructive so it doesn't really work with things involving negatives (unless you make it using some tricks), and so proofs by contradiction cannot be made in Haskell.

As an example of a type you cannot prove in haskell without shenanigans is ((a -> (forall x. x)) -> (forall x. x)) -> a Which is just a weird way of saying double negation.

user

@pxeger what about in c++ where you can mutate things and do dark magic?

(I know curry howard covers that too but never understood exactly how)

thejonymyster

i dont know c++ but i would assume that "mutate" happens after "instantiate"

pxeger

I don't know much about C++ but I'm gonna guess its type system is probably unsound anyway

Wheat Wizard

Most practical type systems represent inconsistent logics.

Inconsistent means you can prove any statement.

pxeger

7:30 PM

@lyxal Did you know that you have bytes? Meta rules say that you do, and so do I. And I believe that until proven otherwise every Jelly, 05AB1E, and Husk answer is beatable.

graffe

7:58 PM

Hello!

Adám

Hi.

graffe

How are things?

thejonymyster

It's all too horrible for words :-) trying to get my oeis sequence posted ~~so i can use it in a challenge~~

do any langs have a "greater than or less than" operator

forest

8:23 PM

@thejonymyster Yeah !=

(In some dialects of BASIC, it was literally <> instead)

thejonymyster

@forest != != <> :P but fair answer

forest

@thejonymyster Was <> not the same?

I thought it was the non-equivalence operator.

thejonymyster

i guess what i mean in more depth is

is there a lang where not all values are comparable, and there is an operator that checks if two values are related such that one is greater than the other

idk how else to phrase it better but surely theres a way

forest

Do you mean foo(a, b): a < b || a > b?

thejonymyster

yeah exactly

that, but as one operator

which i guess wouldnt be useful in many langs

forest

8:30 PM

How is that different from foo(a, b): a != b?

Either way, if a and b are equal, it returns false, otherwise true.

thejonymyster

itd be in a lang where a and b can be not equal but not have one be "greater" than the other

forest

Oooh I get what you mean.

thejonymyster

yeah but its not really practical the more i think of it

but im still curious if any langs have a separate operator for it

itd imply some weird things about the language

Wheat Wizard

Some things can be compared for equality but not ordered.

thejonymyster

yeah but i cant think of when youd use <> and not != either way

Wheat Wizard

8:31 PM

For example complex numbers.

forest

Well in BASIC, <> is !=.

No idea about other languages.

thejonymyster

@WheatWizard right that was another thing i thought of but usually you just use magnitude, and if not, <> would be a bad way to "find out" if youre using complex numbers lol

forest

@WheatWizard Sure, and there are languages that would throw an exception if you tried to compare two numbers like that, but that's them failing the comparison, not the comparison evaluating false.

Wheat Wizard

Yes, so <> imposes an extra restriction on the types.

Just like liftM2 does the same as liftA2, but requires a stricter type.

Partially ordered set

In mathematics, especially order theory, a partially ordered set (also poset) formalizes and generalizes the intuitive concept of an ordering, sequencing, or arrangement of the elements of a set. A poset consists of a set together with a binary relation indicating that, for certain pairs of elements in the set, one of the elements precedes the other in the ordering. The relation itself is called a "partial order." The word partial in the names "partial order" and "partially ordered set" is used as an indication that not every pair of elements needs to be comparable. That is, there may be pairs...

thejonymyster

when does <> return true for complex numbers btw

in a complex number system, is 1<2 still true

forest

8:35 PM

In a complex number system, there is no such thing as "1" or "2" on their own.

thejonymyster

ah, so 1+0i </> 2+0i

forest

In fact, i == i is false.

thejonymyster

wow ok

Wheat Wizard

No definitely not.

i does equal itself.

thejonymyster

yeah that seems drastic

forest

8:37 PM

@WheatWizard sqrt(-1) = sqrt(-1) is false though?

Wheat Wizard

It depends on what sqrt means here.

thejonymyster

well sqrt(-1) having multiple solutions isnt the same as i being multiple numbers

forest

I thought i = i was undefined.

thejonymyster

why would it be?

regardless, what would <> even be useful for? "are these elements able to be ordered"? i guess that could be useful but i feel like you should know that while writing the program already :P

Wheat Wizard

Probably not much, but liftM2, which I mentioned earlier is in the same situation is useful.

thejonymyster

8:41 PM

*able to be ordered and not equal to eachother

which is even more useless xd

clearly we need an <=>, which would at least tell you if one of your arguments is NaN :P

Wheat Wizard

For example all monads must be applicatives, so you need to write both definitions. However sometimes its really easy to just write the monad definition, so you can do that and use liftM2 to fill in the applicative definition for free. liftA2 despite being more general can't do this since it is reliant on the applicative definition itself.

But regardless, partially ordered sets are a thing.

And <> is useful for them.

forest

(OK it looks like I was thinking of comparing two complex numbers, oops)

Seggan

9:14 PM

@forest square both sides, -1 = -1?

Seggan

9:35 PM

CMM: should we repost Interpret Brainfuck to be a little more clear, loose, and up to date with current standards?

Unrelated String

that's a first

thejonymyster

@Seggan that seems ill advised; -i = i, square both sides...

Seggan

@thejonymyster but were talking about sqrt(-1)=sqrt(-1)

thejonymyster

-i and i are both the square root of negative one :P my point is that squaring both sides doesn't guarantee they stay equal

not rigorously anyway

Seggan

11

A: why is $\sqrt{-1} = i$ and not $\pm i$?

The square root function doesn't return two values for positive numbers, or it wouldn't be a function. It's a fact that, if $x$ is a positive real number, there are two real numbers whose square is $x$. The positive one is denoted by $\sqrt{x}$, so the negative one is $-\sqrt{x}$. In this way t...