The Nineteenth Byte

Maltysen

21:00

@LegionMammal978 uh you mean a^(b mod phi(n)) mod n?

flawr

So a^b^c = a^(b^c mod phi(n)) mod n

?

TùxCräftîñg

i think we should create a chat room for decoding this message

Maltysen

@flawr yup

it seems weird, but i there's a cool proof

as I was saying one can write b as k(b//k) + b%k for all k

LegionMammal978

@Maltysen I've never been good at modular arithmetic, just remembered that the totient could be used somewhere in the exponent

Maltysen

@flawr so then, a^b becomes (a^k)^(b//k) * a^(b%k)

then, if you set k = phi(n)

flawr

21:01

Oh thats a very nice proof=)

R. Kap

What?...

Maltysen

you have a^phi(n)^(b//phi(n) * a^(b mod phi(n)) so the first part is 1 by fermat's little theorem

R. Kap

But...but...phi is the golden ratio...

Maltysen

so you're left with a^b(mod phi(n))

flawr

Thinking of it we're making use of the group stucture of the multiplicative group of units of Z/nZ

Maltysen

21:02

@R.Kap also totient

flawr

Thank you very much!!

LegionMammal978

@TùxCräftîñg done

Maltysen

@flawr if c is still too big, you can always recurse this

R. Kap

Interesting...

Downgoat

@Dennis question: Why lock the alex meme post rather than delete it completely?

flawr

21:05

@Maltysen We only need to know b^c mod phi(n), and that is easy to do=)

quartata

@Downgoat so that people don't undelete it

flawr

Again thank you very much.

Maltysen

@R.Kap and there's this famous theorem called fermat's little theorem, which in its general form says that a^phi(n) is congruent to 1 mod n

flawr

A giant leap for me, a little step for mankind.

Downgoat

@quartata though IIRC only mods/CMs can undelete posts that have been deleted by mods

flawr

21:07

@Maltysen It never occured to me that this exponent is phi(n) when you consider Z/nZ!

I always just abstractly considered the group order when considering fermats little theorem

That is really nice!

Maltysen

idk abstract algebra ¯\_(ツ)_/¯ but sure :P

flawr

@Maltysen You should definitely look into it if you ever have the opportunity=)

LegionMammal978

A certain MICHELLE RODRIGUEZ from android.SE just signed up to spy on my Message room for whatever reason ¯\_(ツ)_/¯

Maltysen

do you have any suggestions on where to start?

flawr

It depends on what you already learned?

Are you familiar with linear algebra?

Maltysen

21:09

@flawr kinda not really

Bálint

So, I decompiled stardew valley just to check out the source code, and I found a line with 420 letters in it

flawr

It is not really necessary, but it probably helps a bit.

Helka Homba

Can anyone tell what effect is mentioned around 8:18? Pulfic effect?

Crazy Glasses (HD reshoot)

►

flawr

Then I recommend going into group theory.

Maltysen

any textbook recommnedations?

flawr

21:12

There is a great book that covers all kinds of topics from abstract algebra

LegionMammal978

> You cannot kick a user from this room that has never spoken here.

wat

quartata

Why are you trying to kick someone who is just watching?

flawr

It is really my favourite book ever, and I still use it a lot:

amazon.com/Algebra-2nd-Michael-Artin/dp/0132413779/…

"Algebra" by M. Artin

It is a really fat thing

LegionMammal978

@quartata Good question...

Helka Homba

@LegionMammal978 Because you'd have no reason to. You can always ignore.

flawr

21:14

You can probably find it on library genesis

LegionMammal978

Oh well, have it on Gallery Mode anyway

Bálint

This is my favourite book: amazon.com/...

Helka Homba

@LegionMammal978 People with pure white avatars are worse than lurkers anyway >:|

Maltysen

@flawr thanks!

LegionMammal978

@HelkaHomba [citation needed]

flawr

21:15

It does cover some of the linear algebra, group theory, ring theory, field theory, galois theory and number theory edit: and modul theory

The most beautiful subjects in math=)

LegionMammal978

@flawr Does it cover avocad theory?

Bálint

@flawr Yeah, linear algebra is cool

flawr

@LegionMammal978 Nope.

Maltysen

@flawr found it online

Pimgd

@Bálint not funny, apparently

Phrancis

21:20

Just saw a whole bunch of flags (I think 5) were they all from here?

Downgoat

@Bálint while that message shouldn't have been flagged. Rickrolls are pretty much just spam and annoying

Maltysen

@Phrancis only one here

we marked it invalid

Phrancis

OK thanks for clarifying

Bálint

@Downgoat shouldn't of been flagged?

Pimgd

words are hard

Helka Homba

21:21

yes they is

Pimgd

yeppers

Downgoat

@Bálint >_> it doesn't matter as long as the message came across

PhiNotPi

.com domain price distribution for the flippa.com auction website.

Bálint

@Downgoat It took me 10-15 secs to decipher it

Downgoat

._.

Maltysen

21:23

@Downgoat the period instead of a comma made it especially confusing

Downgoat

@Bálint it's allowed english:

28

A: Is "of" instead of "have" correct?

In speech, this is merely a relaxation of pronunciation - should have becomes should've, must have becomes must've. This relaxed pronunciation is fine. However, the contracted have (i.e. -ve) should not be written as of. Of sounds similar to -ve, so many people erroneously think should of and ...

Maltysen

@Downgoat no its not

> However, the contracted have (i.e. -ve) should not be written as of.

mınxomaτ

I yelled at Microsoft at Twitter (they responded). Worked (I'd like to think). The issue is now fixed. @TùxCräftîñg can you test at your end?

R. Kap

Anyone think this challenge is ready to go on the main page?

1

A: Sandbox for Proposed Challenges

Type It In! code-golfstring Given the input of a sequence of normal keyboard keys and keyboard actions, output the product when all the actions are processed based on the following keyboard: +-------------------------------------------------------+ | ~ | ! | @ | # | $ | % | ^ | & | * | ( | ) | ...

Downgoat

@Maltysen 99% of people don't care and can understand "should of" just as well as "should have", it doesn't matter.

Bálint

21:25

@Maltysen it's

Maltysen

@Bálint ._.

Fatalize

@Downgoat Grammatically it makes no sense whatsoever

of isn't even a verb

Downgoat

why don't we stop being grammar nazis pls

LegionMammal978

Downgoat

@Fatalize would you rather I use "shouldn't've"?

Fatalize

21:26

English grammar is already ridiculously simple, native speakers could make an effort and speak properly

Maltysen

@Downgoat that's allowed

LegionMammal978

Linear algocad

quartata

> ridiculously simple

Downgoat

@Maltysen I know, that's the point, but it's very informal.

Bálint

@LegionMammal978 That's easy, it's [1+avocad 2 + avocad (new line) 3 + avocad 4 + avocad]

quartata

21:27

> aspects of it literally makes no sense whatsoever

Downgoat

I've only heard hillbillies say it

Fatalize

@quartata make*

:p

Downgoat

@LegionMammal978 ಠ_ಠ

quartata

> joke

Maltysen

@Bálint error invalid dimensions

flawr

21:28

@Fatalize ofcof of of o forb

R. Kap

@Bálint *avocado

quartata

Seriously though I'm a native speaker and I think English grammar is kinda dumb in some ways

LegionMammal978

@Bálint Is avocad even a tensor?

Maltysen

@LegionMammal978 but you can't add scalar to matrix (unless its like matlab)

Fatalize

@quartata Regardless of whether kit's dumbd or not, there are very few things to know

Bálint

21:28

@Maltysen There is no such things as "invalid dimension" in linear avocado

quartata

@LegionMammal978 You can't add a scalar and a matrix though

Fatalize

should be, should do, should say, etc. => should HAVE

how is that difficult

to get

quartata

It isn't. But the way should've is pronounced sounds like should of, as a result regional things emerge where people write it like that in informal contexts

Downgoat

@Fatalize Got it. I'll be sure to run every chat message here through Grammarly.

flawr

I noticed some things that native speakers seem to get wrong more often that people who had to consciously learn it.

Bálint

21:29

@Downgoat Would you rather I use "shouldn't've"? I don't understand this sentence

mbomb007

@MartinEnder You should answer this challenge in Retina: codegolf.stackexchange.com/questions/66202/product-over-a-range

Though Retina was a diff version then

Downgoat

@Bálint Instead of "shouldn't of", which sounds nearly identical to "shouldn't have", I'm asking if Fatalize would prefer I use, "shouldn't've", which is very informal English, used mostly by hillbillies, but valid.

Bálint

> Would you rather I use

Downgoat

@Bálint yeah?

Bálint

@Downgoat Would you ...I use

Downgoat

21:36

@Bálint I have no idea what you're saying.

Bálint

@Downgoat Can a sentence have 2 subjects?

Anyone knows, how can I create a new namespace in visual studio?

Downgoat

@Bálint "I" is the object (if I'm remembering how to english correctly)

flawr

Calculator Unboxing #7 (Gaxio) - Numberphile

►

Helka Homba

@Downgoat I don't think "shouldn't've" is hillbilly language. It's just a quick way to say "shouldn't have"

Downgoat

@HelkaHomba I'm talking about in writing

Helka Homba

21:43

ok

Downgoat

I've never seen "shouldn't've" in a book, except in quotes where a hillbilly is speaking.

El'endia Starman

Super weird bug I've got in Pytek right now: an isprime function written in Pytek works properly, except that when you try to print the input, you get 0.

Optimizer

best thing in a Casio calculator is that sqrt(17) returns sqrt(17)

Rainbolt

@Downgoat The hillbillies in Texas say shouldna, not shouldntve (en.wiktionary.org/wiki/shouldna)

Downgoat

texas hillbillies are not only hillbillies

Maltysen

21:50

@Optimizer you have to like 2nd = right?

Bálint

@HelkaHomba IT's not faster to pronounce it IMO

Optimizer

@Maltysen not =, a separate button

LegionMammal978

Even worse:

Helka Homba

According to Google maps, going from San Francisco to Portland takes 10.5hrs by car and 20hrs by train. Whereas going from Berlin to Paris takes 10.25hrs by car but 8-12hrs by train.

Why are europe's trains so much faster o_o

New Main Posts

1

Q: I hate Mondays!

You should a program in language X, which will only output its source code (i.e function as a quine) when it is not a monday. On monday it should output some string with a levehnstein distance of 4 from the source code. i.e if the code is aaaa on sunday it should output aaaa and on monday it coul...

Bálint

21:59

@HelkaHomba Because Europe

quartata

TIL that you can bring Source to its knees with a recursive alias

Bálint

@LegionMammal978 Invalid dimensions

Downgoat

@HelkaHomba People use public transportation more in Europe so I guess they have more incentive to spent more money to make them faster

quartata

I suspect more people would use public transportation in the US if it didn't suck

Martin Ender

@mbomb007 hm, neat. I'll probably answer in the latest version and mark it non-competing though

flawr

22:02

@quartata And if it wasn't restrained by the car and oil industry.

TùxCräftîñg

yay microsoft login is working \o/

Bálint

@HelkaHomba Also, you don't need to go trough so many hills

quartata

@NewMainPosts I still think JS Function string casting shouldn't count as a proper quine

Then again the challenge doesn't mention it needing to be proper at all

Bálint

:30762227 The train from Berlin to Paris doesn't go trough the Alps

Dennis

@Downgoat If I delete, people won't see the note I put at the top.

Bálint

22:03

And third reason: TGV

flawr

@Bálint I meant generally in europe vs usa

Maltysen

@Dennis can't you 11 out most of the content?

Bálint

@flawr Generally, trains are faster in USA, because there are more flat places in the USA

Especially in the western part

Dennis

@Maltysen Not sure I'm getting the point.

quartata

@CᴏɴᴏʀO'Bʀɪᴇɴ Jolf's f needs something for day of the week

Martin Ender

22:06

@mbomb007 oh wait, negative numbers... I think I'll pass...

flawr

@Bálint I don't think so. At least all the trains I considered were quite slow. Most of their track systems aren't built for great speeds.

Bálint

@flawr Currently, in my country trains can only go with 50-60 km/h because of the state of the train tracks

Downgoat

Should the result of nil being cast to a string be Nil or nil?

TùxCräftîñg

@Downgoat i think nil is more logic

Bálint

@Downgoat nil

flawr

22:15

nile

TùxCräftîñg

But sometime, the name is capitalized, like with C#: true => True for example, so Nil is also enviseageable

Downgoat

constants like true are lowercase so I'll go with nil

Bálint

@Downgoat Why do you use nil instead of null?

TùxCräftîñg

nil is shorter

Downgoat

@Bálint I just like nil. To me it just looks neater

flawr

22:23

How abot oh =)

Cᴏɴᴏʀ O'Bʀɪᴇɴ

@quartata will do once I get home

Helka Homba

@Geobits I think npr stole your avatar

Bálint

@HelkaHomba That's technically not an image

Helka Homba

I never said it was

In other news frigatebirds are pretty nifty

Maltysen

@flawr are the matrix unit things just like generalizations of i, j, k?

R. Kap

22:34

1

A: Sandbox for Proposed Challenges

Type It In! code-golfstring Given the input of a sequence of normal keyboard keys and keyboard actions, output the product when all the actions are processed based on the following keyboard: +-------------------------------------------------------+ | ~ | ! | @ | # | $ | % | ^ | & | * | ( | ) | ...

The shameless self-promotion continues

Cᴏɴᴏʀ O'Bʀɪᴇɴ

@HelkaHomba that must be where geobits rests

flawr

@Maltysen What are you referring to?

I don't quite understand what you mean by "matrix unit things"=)

Cᴏɴᴏʀ O'Bʀɪᴇɴ

they're 2d array unit things

Geobits

@HelkaHomba Those bastards :|

Helka Homba

Well they turned it 90 degrees which might qualify as fair use

Martin Ender

22:49

it's clearly a parody

TùxCräftîñg

@Geobits yup but your avatar is the downvote button of PPCG, so you logically have stolen your avatar from PPCG forum

Geobits

I didn't do it logically at all. It was an emotional response mostly.

Maltysen

23:06

@flawr the unit matricies e_ij which are all 0 except for the ij position which is 1

flawr

23:23

Except for the ij position where i=j?

Do you mean an identity matrix?

Maltysen

@flawr no

flawr

Oh, now I see what you mean

No they form a basis of the vector space of matrices

They are basically like the unit vectors (1,0,0), (0,1,0), (0,0,1) in the three dimensional space.

Maltysen

@flawr that's what I meant by i,j,k :P

Luis Mendo

Canonical basis, that's called, right? :-)

Maltysen

thanks

flawr

23:25

Any vector in this space can be uniquely described as a linear combination of those

@Maltysen I thought you were talking about the quaternion ring=)

Luis Mendo

@flawr You and your crazy mathematician stuff

Maltysen

@flawr i just finished vector calc, so engineering notation for vectors is still stuck in my head

Downgoat

Question: Should empty strings be falsy? What about empty arrays?

flawr

@LuisMendo ಠ_ಠ "PhD in Telecommunication Engineering"

Maltysen

@Downgoat IMHO yes and yes

Luis Mendo

23:27

@flawr :-) So?

Downgoat

@Maltysen okay. Anything else that sohuld be falsy besides nil and false and 0?

flawr

@LuisMendo I'm sure you do a lot of crazy math too.

@Downgoat maybe is falsy too

Luis Mendo

@flawr you've got a point there

flawr

But it is also true-y

Cᴏɴᴏʀ O'Bʀɪᴇɴ

@Downgoat idea: have an option for the user to define something as truthy or falsey

flawr

23:28

@LuisMendo Even dirty analysis stuff!

Maltysen

@CᴏɴᴏʀO'Bʀɪᴇɴ was just gonna say this

Downgoat

@CᴏɴᴏʀO'Bʀɪᴇɴ that will be possible

Cᴏɴᴏʀ O'Bʀɪᴇɴ

@Maltysen get out of my head >_>

Maltysen

have em override is_truethy

Cᴏɴᴏʀ O'Bʀɪᴇɴ

maybe a symbol or someting

Downgoat

23:29

class thing {
    cast Boolean {
        return self.isFalse()
    }
}

flawr

is_maybe_truethy_maybe_not

quartata

@CᴏɴᴏʀO'Bʀɪᴇɴ There's a problem with type coercion in Jolf

Maltysen

@Downgoat are you gonna have tuple or set or dict or such? Empty of those should also be falsey

quartata

I had to use \x10 to cast the Date to a string

It should cast automatically like in regular JS

And +1234"asdf" doesn't work

Cᴏɴᴏʀ O'Bʀɪᴇɴ

because numbers don't join

+P"1234""asdf"

Maltysen

23:31

@Downgoat also NaN

Cᴏɴᴏʀ O'Bʀɪᴇɴ

@quartata give me an example?

quartata

@CᴏɴᴏʀO'Bʀɪᴇɴ They should be able to, this is golfing :P

1

A: I hate Mondays!

Jolf, 19 bytes ? hf3"Mon"q+q"asdf Way, way too long. Contains unprintables, hexdump coming in a few moments.

Code is ? h\x10f3"Mon"q+q"asdf

It should be ? hf3"Mon"q+1234q

Two bytes shorter

Cᴏɴᴏʀ O'Bʀɪᴇɴ

I saved you some more bytes

Downgoat

@Maltysen there is no NaN yet

flawr

How about NaB (not a boolean)

NaF not a function

Cᴏɴᴏʀ O'Bʀɪᴇɴ

23:37

NaP not a prime

flawr

NaCOB not a @CᴏɴᴏʀO'Bʀɪᴇɴ

Cᴏɴᴏʀ O'Bʀɪᴇɴ

NaCSOB ftfy

flawr

S?

Helka Homba

Aviation just got their cool design

Downgoat

@HelkaHomba (sorta ninjad)

> an attitude indicator

flawr

23:39

That reminds me of my friends in one of the very first math lectures: We were presented with a theorem: "If A is a matrix (...)". Now he was asked to prove it. He began "Suppose A is not a matrix.*

Downgoat

XD

oh wait nvm that's correct :|

Helka Homba

Attitude indicator

An attitude indicator (AI), also known as gyro horizon or artificial horizon or attitude director indicator (ADI, when it has a Flight Director), is an instrument used in an aircraft to inform the pilot of the orientation of the aircraft relative to Earth's horizon. It indicates pitch (fore and aft tilt) and bank (side to side tilt) and is a primary instrument for flight in instrument meteorological conditions. Attitude indicators are also used on manned spacecraft, where they indicate the craft's yaw angle (nose left or right) as well as pitch and roll, relative to a fixed-space inertial reference...

Maltysen

@HelkaHomba it looks like half their logo didn't load on HNQ

really bothering me

Cᴏɴᴏʀ O'Bʀɪᴇɴ

@flawr le middle name

Helka Homba

it does look squat and blobby

flawr

23:41

@CᴏɴᴏʀO'Bʀɪᴇɴ Conor Sean O'Brien?

Cᴏɴᴏʀ O'Bʀɪᴇɴ

no

you'll never guess it

Helka Homba

@Downgoat fish (and goats) aren't allowed to be ninjas

Downgoat

;_;

yesterday, by Downgoat

8 hours ago, by Downgoat

Jun 10 at 20:24, by Eᴀsᴛᴇʀʟʏ Iʀᴋ

stop-discrimination-against-animals

Helka Homba

They can be ninjimals I guess

quartata

@CᴏɴᴏʀO'Bʀɪᴇɴ Sooo much better. I don't know why I did "asdf kek

Cᴏɴᴏʀ O'Bʀɪᴇɴ

23:43

@quartata :3

Maltysen

@CᴏɴᴏʀO'Bʀɪᴇɴ samantha >_>

Cᴏɴᴏʀ O'Bʀɪᴇɴ

nope

Downgoat

@HelkaHomba :D

@HelkaHomba itunes.apple.com/us/app/spring-mountain-goat-ninja/id929903702

Helka Homba

What are some other words for "automata" (as in ca or fsm kinda thing)

Downgoat

State/Turing machine?

Dr Green Eggs and Iron Man

23:52

imgur.com/gallery/4SDCAs1

Downgoat

@DrGreenEggsandIronMan ;_; bellyflop, ouch

Dr Green Eggs and Iron Man

@Downgoat Does V still freeze if you git pull and then comment out lines 113-114 of v.py ?

Downgoat

uh, lemme see

Python2 or python 3?

Dr Green Eggs and Iron Man

2.

Unfortunately. ;_;

Downgoat

what's the usage agian?

Geobits

23:57

@HelkaHomba Golem

Dr Green Eggs and Iron Man

python main.py source

Maltysen

@Geobits ...

Geobits

>_>

Downgoat

$ echo "iHello" > test
$ python2 v.py test

Dr Green Eggs and Iron Man

or python main.py source -f input or

Downgoat

23:58

no freezing but I can't see any output

Geobits

Oh, right, it should be plural. Golems

Dr Green Eggs and Iron Man

@Downgoat It should be main.py not v.py

Downgoat

:D :D :D :D it works!!!!!!

$ python2 main.py test
Hello

$

but why extra tailing newline

Dr Green Eggs and Iron Man

Most likely 'test' has a trailing newline in it.

if you put an <esc> at the end, that would also fix it.

Downgoat

oh yeah :| it does

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