The Nineteenth Byte

Conor O'Brien

12:01 AM

does that work in J code?

Anonymous

Reddit went down. I'm scared to see the news.

Yodle

@Mego I was just about to ask if it was down for anyone else.

Luis Mendo

@flawr Great answer!! :-)

Conor O'Brien

^ I instantly know he's talking about flawr's rare MATL answer haha

Luis Mendo

@flawr The function table only has a very short description, usually a single word :-( Besides, it doesn't alway duplicate the second-top; only by default. The 70-page spec explains it much better :-P

@ConorO'Brien Heh. Yup! :-D

I still don't see how he computes roots of unity that way

Oh now I see why that 4

orlp

12:11 AM

@EᴀsᴛᴇʀʟʏIʀᴋ yes

@DrMcMoylex it's definitely beatable

I have a solution video

where are you stuck?

mojimonster

@Mego Ow, my AppleScript-friendly heart. </3

@Mego It's up for me. o-o

El'endia Starman

@Lembik: ^ graph of 1-bit flips between 4-bit numbers with at most two bits set.

Anonymous

@mojimonster It just came back up about 10 minutes ago

Anonymous

@mojimonster I would suggest you go to a support group, but first you'd have to find other people who use AppleScript

mojimonster

@Mego /me is destroyed

quartata

12:18 AM

I used to use it

mojimonster

@quartata But then you took an arrow to the Mac?

quartata

Perhaps I could help you move on from it

mojimonster

Nahhh it's really good for automating keypresses.

Which is basically all I use it for.

quartata

that's what they all say

2

New Main Posts

1

Q: Hilbertify an image

I like the Hilbert Curve. Your task for this challenge is to take an image (strictly a square image where all the sides are a power of two pixels wide) and unravel it line by line in a zig-zagging fashion and ravel it back up in a pseudo-Hilbert curve. Unraveling To unravel you will start wi...

Eᴀsᴛᴇʀʟʏ Iʀᴋ

12:32 AM

@Mego yes

@mojimonster what's wrong?

mojimonster

@EᴀsᴛᴇʀʟʏIʀᴋ Mego is rekking me for using AppleScript

Eᴀsᴛᴇʀʟʏ Iʀᴋ

ouch

Conor O'Brien

@quartata do you know a way to catch an error in J, handle it, then throw it back?

Eᴀsᴛᴇʀʟʏ Iʀᴋ

anybody know how to install J for the command line on a mac?

Conor O'Brien

lol

Eᴀsᴛᴇʀʟʏ Iʀᴋ

12:37 AM

homebrew has no formulas, and the wobsite has no link to download it

quartata

@ConorO'Brien I assume you're using try. and catcht.?

Just throw. again. You need to use a global anyways to actually pass along something

Eᴀsᴛᴇʀʟʏ Iʀᴋ

@mojimonster how the fuck do i uninstall jconsole

>_<

that java console thing

quartata

You shouldn't need to?

Eᴀsᴛᴇʀʟʏ Iʀᴋ

?

quartata

I mean just have something like /usr/local/j64-805/...

Eᴀsᴛᴇʀʟʏ Iʀᴋ

12:41 AM

@quartata there doesn't appear to be a command line utility for J for mac

@quartata there is none on my computer

it's only a .app in /Applications/j64-805

quartata

Look inside the app.

Eᴀsᴛᴇʀʟʏ Iʀᴋ

for what?

quartata

It'll be there, trust me.

mojimonster

find is your friend

quartata

@EᴀsᴛᴇʀʟʏIʀᴋ jconsole.sh or something similar.

mojimonster

12:41 AM

Also, .apps are really directories.

Eᴀsᴛᴇʀʟʏ Iʀᴋ

i can't run bin/jqt.command, bin/jconsole, or bin/jqt

@mojimonster exactly

quartata

It's jconsole.sh on Linux

mojimonster

So... show package contents, and dive in?

Eᴀsᴛᴇʀʟʏ Iʀᴋ

it should be j64-805/bin/jconsole, but that doesn't work

@mojimonster that's what I'm doing

mojimonster

Use find, then.

quartata

12:42 AM

Look in Resources, it won't be in MacOS most likely

Eᴀsᴛᴇʀʟʏ Iʀᴋ

wait i got it

mojimonster

find / 2> /dev/null | grep -i jconsole

Eᴀsᴛᴇʀʟʏ Iʀᴋ

it was jconsole in that, but i was using it wrong

mojimonster

k

Eᴀsᴛᴇʀʟʏ Iʀᴋ

@mojimonster already did that, that did work tho

mojimonster

12:43 AM

Nailed it.

Eᴀsᴛᴇʀʟʏ Iʀᴋ

nice

Conor O'Brien

   monad define ''
  try.
    echo u: >@".&.> '2' ; '4'
  catcht. exit 0
  end.
)
|domain error
|   echo     u:>@".&.>'2';'4'

@quartata

@mojimonster wait are you vtc

Eᴀsᴛᴇʀʟʏ Iʀᴋ

yes, he is

Conor O'Brien

that's not confusing at all

mojimonster

@ConorO'Brien :)

quartata

12:45 AM

@ConorO'Brien I can't read this because it's written in tacit goop

mojimonster

I changed my name on a whim and am regretting it

quartata

And you're using ". so I know for sure you're doing something bad

Eᴀsᴛᴇʀʟʏ Iʀᴋ

lol

what's the source of the name @mojimonster?

mojimonster

@EᴀsᴛᴇʀʟʏIʀᴋ this image

Conor O'Brien

@quartata that's not always bad. I'm just converting strings to numbers

@quartata it's not that hard to read

Eᴀsᴛᴇʀʟʏ Iʀᴋ

12:46 AM

@mojimonster oic

quartata

@ConorO'Brien At minimum you could have used parens though

Conor O'Brien

@quartata it was a quick example :P

mojimonster

I put it in an MC chat, took a picture, turned it sideways, and decided it was an emoji monster -> @mojimonster

quartata

@ConorO'Brien Well most likely the issue is in that line and not the try specifically

Eᴀsᴛᴇʀʟʏ Iʀᴋ

@mojimonster what was it?

mojimonster

12:47 AM

@EᴀsᴛᴇʀʟʏIʀᴋ >:D

Eᴀsᴛᴇʀʟʏ Iʀᴋ

oic

Conor O'Brien

@quartata yes. the error is thrown by the line inside the try. I presume try. would catch it?

quartata

Oh wait, I see what you're saying.

Nevermind.

you don't use catcht.

Conor O'Brien

oh?

catch.

quartata

Just catch.

catcht. catches throw. specifically

Conor O'Brien

12:50 AM

ok. now how do I throw the error caused after handling it?

quartata

You don't

throw. just takes you to catcht.

Conor O'Brien

oh. so there is no way to throw the error caught

quartata

@EᴀsᴛᴇʀʟʏIʀᴋ Here it is in action by the way:

in Non-Euclidean Level Design, Jun 20 at 15:20, by quartata

@El'endiaStarman Yeah, here you go: https://www.mediafire.com/?cb86n2p66brms63

Eᴀsᴛᴇʀʟʏ Iʀᴋ

how open it?

quartata

put in portal2/maps

Eᴀsᴛᴇʀʟʏ Iʀᴋ

12:58 AM

kk

i'll test it out later

Conor O'Brien

@quartata in case you are interested, I have made J quite readable

quartata

then map p2_test

Eᴀsᴛᴇʀʟʏ Iʀᴋ

kk

orlp

@quartata have you tried to beat my portal 2 level?

@EᴀsᴛᴇʀʟʏIʀᴋ where are you stuck

on my level

Eᴀsᴛᴇʀʟʏ Iʀᴋ

very beginning, though TBF I haven't tried really hard

quartata

1:02 AM

@orlp No, haven't seen it yet.

orlp

I mean

it's a one room puzzle

@quartata steamcommunity.com/sharedfiles/filedetails/?id=807899652

Eᴀsᴛᴇʀʟʏ Iʀᴋ

@orlp also, your level gave me an achievement, the drop cube on button one

mojimonster

Guys

orlp

@EᴀsᴛᴇʀʟʏIʀᴋ but what did you figure out so far

mojimonster

I just finished my Honors Applications

Conor O'Brien

1:03 AM

@quartata sorry to bug you but jext

mojimonster

Wish me luck

Conor O'Brien

@mojimonster nice! what is it?

quartata

@ConorO'Brien I've been meaning to getting around to making lazily-evaluated versions of the J stdlib

not a feature request or anything

mojimonster

@ConorO'Brien So, for uni, I chose to apply for both standard admissions and honors admissions.

Conor O'Brien

@mojimonster oh, fantastic!

Eᴀsᴛᴇʀʟʏ Iʀᴋ

1:04 AM

@orlp like nothing it was like 2am

@mojimonster nice!

@mojimonster where do you want to go if you don't mind me asking?

mojimonster

@EᴀsᴛᴇʀʟʏIʀᴋ Several places, but my top school is MIT. Probs won't get into that one tho

Eᴀsᴛᴇʀʟʏ Iʀᴋ

nice!

quartata

@orlp subscribing

Eᴀsᴛᴇʀʟʏ Iʀᴋ

@quartata that looks epic

quartata

@EᴀsᴛᴇʀʟʏIʀᴋ You tried it?

Eᴀsᴛᴇʀʟʏ Iʀᴋ

1:07 AM

yep

quartata

I mean, it isn't really a level. Just a demo.

Eᴀsᴛᴇʀʟʏ Iʀᴋ

yeah

the door thing though is so cool

@quartata just wondering, do you play tf2 with it fullscreen or windowed?

quartata

Windowed, 1280x720

Why?

Eᴀsᴛᴇʀʟʏ Iʀᴋ

because you seem to have good ideas/methods to be good at tf2, and was wondering if you played it fullscreen to have max view of the surroundings or somethign

quartata

Nah, only the actual aspect ratio affects that.

DrMcMoylex

1:12 AM

@quartata How good are you at UE? I'm improving but not that great

quartata

I know very little.

Source and the various iD Techs have been the only 3D game engines I've worked with extensively

@orlp Your Aerial Faith Plates aren't quite set up correctly: unless I strafe it lands me on top of the glass instead of on the target

Unless that's deliberate....

wait a second

DrMcMoylex

OK. I might bug you for help sometime down the road...

@DrMcMoylex Why the heck does this have two stars?

quartata

@orlp I think I might have just figured it out

I was wondering why you started out higher up....

and why the funnel

Eᴀsᴛᴇʀʟʏ Iʀᴋ

@DrMcMoylex no clue

quartata

Shoot, I end up in the other funnel..

Hrm.

@orlp OK, I got the cube to the other side on the first room.

It doesn't block the laser for long enough though

I guess I need to cut the funnel right when it's above the glass huh

orlp

1:26 AM

@quartata did you already spot the second laser?

quartata

eh?

orlp

if you interrupt the main laser

quartata

I'm still on the first room. I got the funnel going across

orlp

there is only one room

quartata

Oh. OK.

orlp

1:27 AM

its a one-room puzzle

quartata

Well I'm about to interrupt the main laser

orlp

if you interrupt the main laser

a secondary laser activates

that (re)spawns a cube/sphere you need to solve the puzzle

Eᴀsᴛᴇʀʟʏ Iʀᴋ

i don't even know how I got the round cube to spawn

but it just did

orlp

I just told you :)

I wish I could make the level more intuitive

Eᴀsᴛᴇʀʟʏ Iʀᴋ

but i didn't interrupt it?

orlp

1:28 AM

in terms of what is connected to what

quartata

No, I like that it isn't obvious.

orlp

@quartata well you see

the level has a very interesting solution

but I feel most of you get stuck before that point

so you never get to explore the actual limitation

but maybe I'm wrong

quartata

Darn, I did it a little too late

Oh wait

The cube just has to be on the panels?

Eᴀsᴛᴇʀʟʏ Iʀᴋ

I don't even know how to get the cube past the first disintegration field

Geobits

What have I done? Note to future self: Don't start 144 downloads at once. It really bogs things down.

Eᴀsᴛᴇʀʟʏ Iʀᴋ

1:30 AM

your computer becomes a bog site, @geobits?

Geobits

Exactly :D

Oh god even typing is laggy.

quartata

@EᴀsᴛᴇʀʟʏIʀᴋ Place a portal below the funnel and another on the floor

Conor O'Brien

forkbombs cause more lag

quartata

Go back up the funnel, then move that portal to past the other field

Eᴀsᴛᴇʀʟʏ Iʀᴋ

@quartata oh shit

quartata

1:31 AM

Then you just need to carry the cube with you to dodge the first funnel and get out

Then drop the cube on the panels on the far side

That turns off the trigger_hurt lasers

And raises the panels up to the laser

@orlp Ooh now there's two cubes

I don't see where the other laser is though

Ohh I need to stack the cubes to keep the laser off

Eᴀsᴛᴇʀʟʏ Iʀᴋ

orlp, your level borked

i died and now I'm stuck in the ceiling

well, in the panels that fold out from under you, they suddenly folded back

quartata

Crap, the cube between the lip of the ceiling and the panels.

I can't get it out now

Need to toggle the edgeless safety cube I guess

Or just pause and unpause and have it magically get unstuck

@orlp Wait, what the heck. The second cube disintegrates when I toggle the laser off...

orlp

@quartata ah

you see

NOW you've found the main puzzle

:)

remember what I said about the second laser?

that (re)spawns your cubes?

Conor O'Brien

@quartata last J question of the night then I'll leave you in peace: is there a reference for predefined functions in J? e.g. echo

orlp

@EᴀsᴛᴇʀʟʏIʀᴋ sorry :(

quartata

1:42 AM

@orlp Oh, I think we're talking different lasers

This whole time I've been talking about the thermal discouragement beam

orlp

@quartata go to where the sphere is

Eᴀsᴛᴇʀʟʏ Iʀᴋ

@orlp how do you activate the spheere dropper?

quartata

Is the first laser the trigger_hurt that blocked off the panels originally?

orlp

@EᴀsᴛᴇʀʟʏIʀᴋ interrupt the main laser that goes across the room

@quartata I don't understand the question

quartata

Like, I only see one laser.

orlp

1:43 AM

@quartata go to where the sphere is

the go to the corner opposite of it

that's the unintuitive part I meant

Eᴀsᴛᴇʀʟʏ Iʀᴋ

there's a non-activated laser there

quartata

Yeah, I see that.

orlp

I want to make that more visible

quartata

But it isn't on.

orlp

exactly

it turns on

quartata

1:43 AM

Oh.

Ohhhhhh

orlp

when the other laser turns off

couldn't you follow the markings?

Eᴀsᴛᴇʀʟʏ Iʀᴋ

@orlp with what? my body?

quartata

OK, I get it now.

orlp

on the walls? to see those are connected

@EᴀsᴛᴇʀʟʏIʀᴋ that doesn't work, you have to interrupt it with a cube

quartata

@orlp I didn't realize at first that was a laser. I thought it was an edgeless safety cube button

Eᴀsᴛᴇʀʟʏ Iʀᴋ

1:44 AM

@orlp exactly, that part is really confusing me

quartata

I recommend you put up one of the laser signs by it.

Eᴀsᴛᴇʀʟʏ Iʀᴋ

@quartata yeah, so did I

maybe a laser sign near it?

ninja'ed

orlp

@quartata is that in the default editor?

this entire level is default editor

quartata

Uh, I don't know. It's a decal in Hammer.

orlp

I never used hammer

feersum

1:45 AM

@mbomb007 I think so...

I hate writing a bunch of words though.

orlp

@EᴀsᴛᴇʀʟʏIʀᴋ well, that's your first puzzle then

quartata

I should eat something. Thinking with portals makes me hungry

orlp

get the cube to interrupt the laser :)

quartata

@EᴀsᴛᴇʀʟʏIʀᴋ That's kind of the easy part. Use the funnels like I described

Eᴀsᴛᴇʀʟʏ Iʀᴋ

@quartata oic

quartata

1:46 AM

The hard part is then keeping it that way...

Conor O'Brien

@ConorO'Brien jsoftware.com/help/user/lib_stdlib.htm

quartata

@ConorO'Brien One second I'll look

orlp

by the way if you guys ever REALLY get stuck and want to know the solution, I have a solution video ready :)

quartata

Oh, yep, there you go

Conor O'Brien

@quartata ninja'd :P

Geobits

1:47 AM

Sorry to interrupt the game talk, but does anyone know of a utility that would chop the first X seconds from a folder full of MP3s?

orlp

and the level doesn't require any glitches or mad "throws" to solve

quartata

@Geobits ffmpeg could do that

orlp

@Geobits if you can solve that question for one mp3 you can automate the rest wiht batch

Conor O'Brien

@Geobits don't think of it is as interrupting the convo, but as starting a new thread

orlp

and indeed ffmpeg can solve that for one file

quartata

1:48 AM

@orlp Nah, I'm pretty sure I'm close and I don't want to spoil it

Doorknob

Guess how the designers of this website colored this button. Go on, take a guess.

Geobits

Oh I didn't think of ffmpeg. Brb looking at docs :)

orlp

@Doorknob overlaying it with something that isn't click-through

Doorknob

Not quite that awful.

orlp

@Doorknob the background is red, and everything except the button is colored

feersum

1:49 AM

Tiling 1x1 red images!

Doorknob

Close enough. :P

feersum

70 x 32? Lame.

CMC: How many possible dimensions of rectangle could be used to tile the 70x32 px button?

Geobits

That sounds less like a CMC and more like my kid's math homework.

Except better worded.

quartata

@orlp FWIW Hammer is a pain in the butt to use but extremely powerful. Source I/O is Turing complete and with VScripts the sky is the limit

Squirrel kinda sucks though...

Conor O'Brien

@feersum call me self-advertising, but I'm trying to make J readable, more or less. I thought you might be interested. jext

it basically adds word aliases for each verb, and adds some new functions

H Walters

1:54 AM

@Geobits So ask your kid

Geobits

He's brushing his teeth. Bedtime soon ;)

feersum

Does it have better documentation?

Conor O'Brien

no, not yet. but it will!

hopefully

feersum

hehe

Geobits

> ffmpeg --help
ffmpeg: command not found

How is it even possible that I don't have that installed? :/

orlp

1:56 AM

@Geobits ? just use your package manager to install it

quartata

Make sure you get the real deal. Some distros provide avconv under the name ffmpeg

orlp

not that avconv is bad though

the differences are very minor

El'endia Starman

@Geobits Maybe it's not in your path env variable?

Geobits

@orlp That was my first thought. Gotta find the actual name though -_-

Package ffmpeg is not available, but is referred to by another package.

quartata

@orlp true

ΛεγίωνΜάμμαλϠΟΗʹ

1:57 AM

CMC: Write a program that will make the user's monitor display at least one fully infrared pixel

Geobits

@El'endiaStarman Yeah, I dunno. I've done all kinds of video/audio editing on this computer, so I don't know how it's possibly just not there.

@ΛεγίωνΜάμμαλϠΟΗʹ I'm willing to bet most (all?) pixels leak IR all the time they're lit.

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