The Nineteenth Byte

emanresu A

04:01

I think trigonometry's pretty much the end of stuff that's practically usable in maths

Differentiation and integration seem like they should be, but you can't describe the world with equations.

user

Intégration is very useful depending on what you’re doing

A lot of physics needs it

DLosc

^

emanresu A

Hm okay

user

@emanresuA and you absolutely can describe the world with equations, to an extent

emanresu A

> to an extent

Yeah, pretty much. If you try to describe the movement of a car along a road, you'll end up with an eighteenth-degree polynomial.

user

04:05

Just because we haven’t come up with perfect equations for everything yet doesn’t mean they’re useless

emanresu A

True

user

@emanresuA you can get pretty close with all sorts of approximations

Unrelated String

@DLosc ab is just bc minus some content at the end; not sure anyone ever takes both

user

Machine learning involves much more than trig

Imma stop now because i think you’re close to convince d

emanresu A

I am convincedish now

user

04:07

:)

Unrelated String

i sure am having Fun with vector calculus in the ml class i'm taking this semester lmao

user

And you never know when the most bizarre abstract stuff has connections to real life

PyGamer0

@user no i wont cheat.

user

@UnrelatedString is it like integrals of surfaces over vector fields and studf

If so, i sympathize

Unrelated String

just some pretty simple gradients at this point

DLosc

04:10

@emanresuA The amount of daylight in late March is the same as the amount of daylight in late September; but (if you live far from the equator) the average temperature is warmer in early fall than it is in early spring. Why? Because the temperature tracks (roughly) with the integral of the amount of daylight rather than directly with the amount of daylight.

user

Enough for the infinite mqthematician mosquito joke to make sense?

emanresu A

@emanresuA You can't describe the world perfectly with equations

Unrelated String

we haven't yet

user

So?

Why abandon equations entirely just because they’re not perfect?

emanresu A

Exactly

user

04:13

Wait I’m confused, what side are you on lol

DLosc

@UnrelatedString I'd put a decent amount of money on can't, given that chaos theory is a thing.

emanresu A

@user Yours, I'm just playing devils' advocate a bit

@DLosc And the three-body problem

Unrelated String

i feel like that gets into "prohibitively expensive to simulate" more than "conceptually impossible to simulate"

user

—-Id put a decent amount of money on can’t, given that nukes are a thing—-

Unrelated String

although i guess it depends on the definition of "with equations"

user

04:14

@UnrelatedString you can’t simulate the universe, can you?

emanresu A

@user Dammit, em dashes

DLosc

@emanresuA And undecideability, for that matter

user

@emanresuA maybe i will too for a while

DLosc

@user I think you should. There's nothing funnier than an argument where nobody actually believes what they're saying.

AviFS

Hey guys!!

user

04:17

Since we can’t describe the world perfectly and probably never will, we should all just do whatever

DLosc

(playing devil's advocate advocate)

6

emanresu A

@user You could, but you don't have to.

hyper-neutrino

@AviFS hello! o/

AviFS

Oh Desmos won?

user

@emanresuA of course, i don’t have to do anything

AviFS

04:18

@hyper-neutrino o/

emanresu A

@hyper-neutrino goto sleep

DLosc

@AviFS Yep! Aiden Chow was teaching for a while, then had to leave.

user

Speaking windows ny advocate hat on, i would recommend qll of humqnity getting drugged up and launching ourselves into the Sin

4

hyper-neutrino

@emanresuA it is 11:20 pm why would i sleep now lol

user

It’s late

DLosc

04:20

@user Windows??

hyper-neutrino

he says, in the same timezone as me

emanresu A

@hyper-neutrino Because it'll protect you from Lyxal's fridge, which has developed a mind of its own and is coming for those who tried to destroy it.

user

I meant to say Sun but i think I’ll change back to sin lol

AviFS

I have the alpha version of a project to share!

hyper-neutrino

i already nuked lyxal's fridge once, and I'll do it again

emanresu A

04:21

It's evolved

@user There are a lot more typos than that

user

@hyper-neutrino hey, my phone’s clock is like a minute behind yours because it was like 11:19 for me then

HUGE difference

hyper-neutrino

it was 11:19 when i sent it

i rounded

user

@emanresuA they’re not misinterpret able tho

emanresu A

@user windows is

user

@hyper-neutrino well i rounded from 11:18:99 myself

lyxal

04:22

y'all squabbling over times while I'm just over here installing Java 11

emanresu A

Yes, there are 100 seconds in a minute

user

@emanresuA oh.

AviFS

I'll be adding loads of langs to the backend-- the project concept and front-end are language agnostic. But I have it running right now in APL: avifs.xyz

user

I meant “with my”

@AviFS nice!

emanresu A

@lyxal You might want to check on your fridge

user

04:23

@lyxal install java 17, latest lts with lots of goodies

AviFS

It's an interactive repl-like environment that prints the state on each line, and dynamically updates the affected lines when variables/functions are changed.

lyxal

@user no, because Uni requires 11

user

Uni bad :(

Unrelated String

f

lyxal

is 17 compatable with Tomcat 9?

because that's what I need 11 for

emanresu A

04:24

@AviFS ... why is it trying to connect to localhost:8003

user

Bruh idk

lyxal

we doing java servlets in 2022

AviFS

@emanresuA ...

I--

user

Imagine using java for real life stuff

AviFS

I have a websocket running on an actual cloud server, lmao.

I just changed it.

Sorry, just a sec.

user

04:25

@lyxal those who repeat history are doomed to repeat it

Or something

lyxal

@user well yes

Unrelated String

the one class i've taken in java, i'm not sure it actually told me what version of java the autograder was on
so a few times i'd just submit something that worked perfectly locally and it wouldn't compile

lyxal

@user if you're repeating history, you already are, dumbass.

AviFS

@emanresuA Pretty embarrassing, haha. Fixed and committed. But caching will be a thing.

emanresu A

Also funcs.js 404s

AviFS

04:27

For now, it won't run on Safari. It'll run on Chrome & Firefox, though.

The websocket isn't encrypted and secure enough for Safari... Have to make it a wss:// instead of ws://

@emanresuA Stop breaking it, haha

user

154

Q: Getting Java version at runtime

I need to work around a Java bug in JDK 1.5 which was fixed in 1.6. I'm using the following condition: if (System.getProperty("java.version").startsWith("1.5.")) { ... } else { ... } Will this work for other JVMs? Is there a better way to check this?

Useless to you now lol but might’ve helped

DLosc

@AviFS How does it work? I'm typing stuff, but otherwise it doesn't seem to do anything

user

@lyxal you’re repeating me, stipid

lyxal

@user unless you went to the same uni i do and did the same course I'm doing, then no u

AviFS

@DLosc Sorry, just a sec! I had refactored like two things before sharing it.

How can I force a reload?

Because it's caching on my end so it still works.

user

04:32

Ctrl shift r or fn5 (idk if that’s what you meant)

DLosc

Ctrl-F5 is what I use for a hard refresh

user

Best to use ctrl shift fn5 r for best results :p

lyxal

I use alt+F4

works like a charm

user

Why do so many combos exist for this lol

AviFS

Welp.

I mainly just changed the styling. This is embarrassing.

But yeah, it stopped doing stuff.

emanresu A

04:35

The hardest refresh requires both a Mac keyboard and a Windows keyboard as a security measure, like how missile launch systems require two keys to be turned at once.

Radvylf Programs

@AviFS Ooh, is this the project we'd been discussing in the OISB discord?

Also, if you want wss, and HTTPS in general, I very strongly recommend letsencrypt+certbot: certbot.eff.org/instructions

It's free, takes like 5m to set up, and gives you all the HTTPS stuff plus necessary config

AviFS

This is literally murdering me.

Radvylf Programs

@RadvylfPrograms (Assuming you're on a server you control, and are using something like nginx as a reverse proxy)

emanresu A

> literally

o/, permanently I guess

AviFS

I worked on this for weeks, and it's been working awesomenessly.

I might actually have to figure out how to use git now to go back to the last stable commit.

Oh no. It isn't that. The server just isn't responding anymore? But it's connecting. SSH time.

lyxal

04:53

TIL it's hard to balance a pen on your headphones in the same way you'd balance a pen on your ear without headphones

DLosc

Anybody know a good way to get the LaTeX that corresponds to a particular Desmos graph? I'm looking at some of Aiden Chow's answers, and the claimed code doesn't quite match what I would type to get the same thing (e.g. \min where I typed min and it seems to work fine).

emanresu A

@DLosc ctrl-c but there are tricks to golf the text

AviFS

This is really painful, I don't even know. Oh well. So I had changed from the server's websocket to the localhost websocket for some quick front-end stuff, as I've done loads of time. And I made the mistake of Ctrl-C-ing the cloud server to see if that would help. But now that I'm restarting it, it's giving me all these new errors and it doesn't work anymore. And it's node. It's painful.

DLosc

@emanresuA Oh goodness, there must be. I don't think \left(\right) is necessary. :P

emanresu A

most of the desmos golfing tips are for the text :P

DLosc

05:06

Welp, time to go read the tips question

Radvylf Programs

@AviFS Errors don't appear out of nowhere. Sounds like either you accidentally made changes to the code, or you have something like a conflicting instance of the server using up the port.

AviFS

There's no stable commit to go back to, because it's the server stuff which went all screwy. Git was for the frontend. There must have been a better way to do this.

Radvylf Programs

What's the error text? I've had a lot of experience in horribly and close to irreparably breaking node-based projects, so I might be able to help

AviFS

@RadvylfPrograms Right, I'm trying to figure out if I changed something while it was running. But actually, I think it has to do with the initial connection. It's to do with the in/out response logic, but I've never gotten an error on that particular if statement.

Radvylf Programs

Sounds like one possiblity is that you could be sending invalid data from the front-end, without robust enough error handling on the back-end.

emanresu A

05:11

^

Radvylf Programs

This is where I'd typically add a half dozen console.logs

If in doubt, console.log :p

emanresu A

When in doubt, hack into the mainframe.

Radvylf Programs

Wtf, YT Premium is $12/month?

You could get a netflix or disney+ subscription for that much, and have money left over

Who would pay $140 a year for a download button and a few less ads

emanresu A

Especially when screen recording and adblockers exist

DLosc

Am I doing something wrong or does this Desmos tip not work anymore?

emanresu A

05:21

Seems to sorta work

DLosc

Huh. I couldn't get it to work with the code I just wrote. Guess I'll post it as-is and someone can tell me how to golf it. :P

Oh, great. Now it's not working at all. X^P

Okay, my problem was that I was trying to do sign instead of \sign, I think

AviFS

05:56

Ready to try again? avifs.xyz

DLosc

Aha!

lyxal

Do y'all ever just consider birds and question why we needed birds? Like really, why do birds have to be a thing? Why couldn't we just have no birds? That'd arguably be better for society. But no, we just have to have birds in our lives.

AviFS

Shoot.

New bugs?

Well, for the most part, it's a working demo!

You can try defining variables and functions, then doing stuff with them, then changing them above it.

DLosc

@AviFS Looks like. I put in 2+3 and it gave 5, but then I tried making a longer expression and it still gave 5, and now it's not doing anything.

AviFS

And the relevant entries will update as you type.

@DLosc Yup. Same.

DLosc

06:00

@lyxal No, because 1) the existence of birds is not predicated on whether they're useful to humans, and 2) some birds are delightful.

AviFS

It's a real bummer. It's running perfectly on my local server.

For now, if you reload a few times, it seems to eventually get happy.

lyxal

@DLosc I don't care if they're not predicated on their usefulness to me I don't want them to be at all.

AviFS

Wait, could it be related to multiple people using it at the same time?

Each one should make a new websocket, but they might be affecting each other.

That's the only thing I never tested. And as soon as, I imagine, you stopped playing with it, it started working for me again.

DLosc

@lyxal I do not share or understand this opinion.

lyxal

@lyxal they make loud noise, poop on car and stand around looking stupid

DLosc

06:02

Although I just read about how some birds in Australia apparently spread fires intentionally, so I can see why you'd be upset about that.

AviFS

@RadvylfPrograms Your expertise is wanted!

Yeah.

Keep typing stuff!

lyxal

@lyxal and the moment you try and be friendly with them and approach them, they just run away never giving you a chance to make amends with them.

AviFS

I think it's updating my end, too.

DLosc

Uhh...

AviFS

Did you just put in 20.2?

DLosc

06:03

I typed 2

AviFS

22.2

DLosc

and got 18

AviFS

Are you getting my messages?

DLosc

@AviFS Which ones?

AviFS

Those.

DLosc

06:05

@AviFS No

@AviFS Yes

:P

AviFS

Hahahaha.

Alright, I'll let you try it out then.

No one interfere!

It's broadcasting the messages back to all connected websockets.

DLosc

Lol

AviFS

Which is kinda funny since we can redefine each others variables.

DLosc

It worked for a bit, but now it's saying 1+2+3+4+5 is 24

I haven't even used any variables

AviFS

You found the Easter Egg!

lyxal

06:07

How to define variables?

AviFS

Umm, nevermind.

It's gonna need some work on the web sockets clearly, haha.

lyxal

@DLosc I got your 15

AviFS

But variables in APL are a←42

lyxal

It ended up on my screen instead of yours

AviFS

This one won't break because it runs on the client side.

lyxal

06:08

AviFS

LMAOOOO

Sandbox Posts

0

A: Sandbox for Proposed Challenges

Lexical sum For a given number n, output an strictly decreasing array whose sum is n and its lexical order is the smallest from any possible outputs Smallest lexical order means that for n=9, [5,3,1] is not allowed as you can reduce the 5 to a 4, so the final output is [4,3,2] Testcases 4 -> [3,1...

AviFS

If you want to get a sense for what it's supposed to do, you can play with JS:

avifs.github.io/tabl/#js

DLosc

There's got to be some weird cooperative and/or guessing game possible here

AviFS

and then when you change a it'll update.

Eg, you can do something like:
```
a=4
2+a
```

@DLosc I know! We should totally be able to make some funky interactive esolang cops & robber thing based on a similar premise. Or hidden cooperative code-writing without "blowing up the bomb."

But that wasn't quite the purpose of this one.

lyxal

06:12

It just is

42 just is

No expression needed. The answer is just 42

AviFS

Oooh, we're definitely breaking it.

It's down to a crawl.

I better restart the server now that I figured out how to do that.

...The websockets don't close when you exit or restart, so that's probably part of the problem.

Who keeps sending 5s?

@lyxal

Sandbox Posts

0

A: Sandbox for Proposed Challenges

Stacking art Your task is, given a array of numbers, that is strictly decreasing, output the crate stack Since the array order follows this rule layer 1>layer 2>layer 3..., we have to make sure every layer above the bottom one is centered with respect to the whole width of the layer below it. If ...

AviFS

She's up again. Hard restart.

lyxal

@AviFS ...

AviFS

@lyxal Was that you, haha

avifs.github.io/tabl/#js is hacker-proof if you didn't actually get it working uninterrupted.

lyxal

06:18

@AviFS ...

AviFS

Thanks for testing, I'll leave it up so feel free to play with it when no one is "on." Gotta figure out how to actually use websockets now.

Ummm..

You gotta tell me! Is that some sort of loop or are you doing it by hand?

lyxal

It's an intricate system of autoclicks

The first one opens the keyboard, the second one taps the number 8, the third one hits enter, the fourth one opens the refresh menu and the fifth clicks refresh

Rinse and repeat on a timed loop and you've got fun times for all

AviFS

That's actually hilarious.

lyxal

The 5s were simpler: one on the 5 key and one on the enter key

Each running 50ms after the next

AviFS

I better check the AWS dashboard before I get a bill through the roof, haha. Supposedly I'm covered by time rather than usage, but... I better make sure!

lyxal

06:23

Yikes

I'll hold off on the autoclicker shenanigans until you find out

AviFS

Gonna make a chat room specific just because I have the feeling this is gonna clog up TIO for a few days otherwise.

@lyxal No no, don't you dare. It's brilliant.

I've triple-checked already. But... I'm gonna quadruple check.

And switch over to Digital Ocean, haha

lyxal

@AviFS just until you find out about billing

@AviFS am I safe to continue shenanigans?

AviFS

@lyxal I just hate that it isn't more clear. But supposedly yeah, that's how it works. It's just a free tier EC2 instance so it's not supposed to try and auto-scale on me, which is how people rack up obscene bills.

From what I understand, the worst that happens is it just grinds to a halt and you have to hard restart it.

So yes, please go ahead!

lyxal

I'll do my worst a bit later

I gotta go for now

AviFS

Sounds good.

@Adám You might be interested. I think everyone's off it for now.

Gonna do this in the tabl room to not clog up TNB.

DialFrost

06:38

can someone check these 2 new challenges thx

codegolf.meta.stackexchange.com/questions/2140/… codegolf.meta.stackexchange.com/questions/2140/…

Aiden Chow

07:45

@UnrelatedString the consensus on scoring Desmos submissions is that the code works properly when pasting in the raw text into the Desmos graphing calculator without any further modifications, which includes the auto-complete feature that Desmos has.

Unrelated String

interesting

so anything that autocompletes with keystrokes but not copy paste is invalid

Aiden Chow

@UnrelatedString yes, thats sounds about right

Aiden Chow

07:58

@DLosc see my comment under your post. i think the problem you were having was that you were pasting the entire code into Desmos all at once. if you paste in each line one at a time, it will work. pasting in one equation at a time seems to be allowed.

emanresu A

08:30

@AviFS ⍳1e9 1e9 - sorry

ophact

How do you do conditionals in desmos?

emanresu A

You can do piecewise

{condition: result, [condition: result], [default]}

ophact

Never thought of that, wow

Aiden Chow

@ophact yeah, as emanresu said, a piecewise

you can apply this tip if you can.

oops wrong link

this tip

ophact

That's the same link

Aiden Chow

08:33

@ophact oh really?

oh yeah

facepalm

SegFaultPlus4

@DLosc is desmos even turing complete

is it even a language

emanresu A

Yes

Aiden Chow

@SegFaultPlus4 yeah it is

ophact

It should be turing complete...

emanresu A

It is turing complete

Google it

ophact

08:35

No recursion right? I tried it for recursive factorial and it didn't work

Then how does it loop?

Aiden Chow

@ophact actions

ophact

Is there something I'm missing?

emanresu A

Actions / ticker

Aiden Chow

help.desmos.com/hc/en-us/articles/4407725009165-Actions

emanresu A

Type a -> a + 1

And stuff should appear

7

Q: Is Desmos Turing-Complete?

The graphing calculator Desmos has a ton of functions, and can express any arithmetric formula. What I want to know is, is it Turing-Complete? Desmos supports, among other things: Most mathematical operations / functions Multiplication, addition, subtraction, division, modulo, etc Sum and produ...

turing-completeness

Aiden Chow

08:38

@emanresuA nice, i should probably make a similar post for geogebra cause i genuinely have no idea if geogebra has infinite loops

@SegFaultPlus4 see this post for further details

SegFaultPlus4

09:11

@RadvylfPrograms you should (re)make cookie clicker

AviFS

Looks like the websocket bugginess from before has to do with the hacky hair-pulling I did to get APL piping properly. It looks like the logic for the main websocket is just fine after all. The issue was that I was using a second websocket on the backend to deal with APL. That's what made it look like broadcasting, because after sending it down along the websocket chain, the primary one didn't know which client to send it back to.

Compiled langs are back on hold, but here's a demo with Vyxal this time. It should handle multiple people now!

avifs.xyz

emanresu A

Yay, Vyxal :)

AviFS

Also, Safari's working now, too. I think because that domain is insecure (http vs https), so it's not complaining about ws vs wss anymore.

emanresu A

Permission to try break it?

AviFS

Feel free to respond in the tabl room, if you'd prefer.

@emanresuA Absolutely, positively and always.

emanresu A

09:21

Oops, broke it already

by accident

(I was trying to see if you'd disabled †)

AviFS

(There's a multiline mode somewhere, but it maintains the stack by design to allow for interactive code writing where you can see the code state as you write. So you're encouraged to break your code into semantically meaningful lines for self-documenting code on the right. And then you can see the stack change through as you feed in different input at the top.)

@emanresuA Haha, infinite loop?

It's seriously dumb right now.

emanresu A

@AviFS No, just pushing 1e11 ones to the stack

AviFS

checking + timeouts + safety = 0

@emanresuA code?

Is it like, generally working though?

I don't actually know any Vyxal to play around with it.

emanresu A

Yep, it's quite nice to use

@AviFS 10:e(1

AviFS

@emanresuA Ah yeah, that's not doing much.

With Dyalog I never hit a number too big, haha

But the Vyxal-Python transpiler's not quite there yet :p

emanresu A

09:29

@AviFS Try ⍳1e9 1e9 - or don't

AviFS

What's a long but straightforward Vyxal answer on CGCC that I can copy/paste in to watch the stack?

emanresu A

I don't really understand what ⍳ does but the results grow pretty fast

@AviFS Is there any input support?

AviFS

It's all there in the code, but I added nothing to the UI.

Got too perfectionistic and it was gonna make me miserable, haha

But tomorrow I can make a skeleton to allow configuring all that stuff, and show everything.

It's also sending back the output.

What gets displayed on the right is the state, not the output. If you print something with the , command, it'll just pop off the stack and disappear. But it's there in the JSON.

emanresu A

But yeah, pretty cool

PyGamer0

ok i got my computer project

^ that is the first question

emanresu A

09:36

x in [3025,9801, 2025] (afaik that's all)

PyGamer0

soo is that all possible values of that "tech" number

@emanresuA i have to do that in java

and if i use membership tests ill get 0

lmao

mathcat

wohoo desmos

mathcat

09:52

didn't know about actions before

Adám

@AviFS In?

AviFS

@Adám Expired! But she'll be back round again. An APL interface, and I saw you had just joined the room.

@lyxal Darn! I'm off for the bed now, but there's some Vyxal for you.

lyxal

It doesn't seem to like maps

₁ƛ₍₃₅kF½*∑∴ just gives an empty string

Try it Online!

mathcat

@AviFS what does it do?

an online interpreter?

lyxal

Think of it as a sort of interactive notebook

You type expression, it shows stack on the right

And it updates stack as you type

mathcat

10:06

nice

AviFS

(You can also change stuff above it, and it'd dynamically update everything affected.)

emanresu A

o/, i need sleep

AviFS

What Lyxal said! More generally, it shows some kind of meaningful state interactively on the right as you type, but right now I'm just leaving Vyxal up as the only language until the Vyxal folks are happy with it. Then I'll add other langs; everything is written to be lang-agnostic.

mathcat

(o/)*2

AviFS

o/

@lyxal That'll be an easy fix tomorrow. It's running the official python vyxal interpreter on the backend, so it supports everything. But I wasn't sure what data types I had to support for pprinting. I don't think I told pprint how to display an array, so it's defaulting to the empty string.

lyxal

10:23

Fun fact: the value of a single robux is more than the value of a single ruble

gg putin a video game currency is beating your own nation currency.

pxeger

Any feedback?

SegFaultPlus4

@lyxal lol

PyGamer0

10:58

@lyxal its not robux its bobux :p

Transcript for