The Nineteenth Byte

Using built-in functions to do the work Mathematica is a big one for this, with Fibonacci[n] to calculate the n'th Fibonacci number.... I have no objection to these being posted as a side note within the main answer though - that is interesting and helps me learn different languages capabilitie...

ETHproductions

Otherwise CJam and Pyth would violate that loophole.

isaacg

Which has 47 upvotes and 44 downvotes.

Exactly.

ETHproductions

1:42 AM

Wow, these new 750 rep features are nice :)

isaacg

Such as?

ETHproductions

Seeing up/downvote specifics.

Wow, 91 votes on an answer, and only 3 to show for it.

isaacg

On the binary lambda calculus front, it can do primes in 167 bits, which is pretty good imo.

ETHproductions

I really need to check out that language...

PhiNotPi

@isaacg I don't really seem to understand BLC...

ETHproductions

1:56 AM

xkcd.com/1319

I run into this so often xD

PhiNotPi

Such as... where does it do arithmetic, or any other operation, really?

PhiNotPi

2:35 AM

I don't really know if there's much I can add to a golfing language without creating a CJam clone.

isaacg

2:47 AM

@PhiNotPi It doesn't - there's no built-ins at all.

PhiNotPi

If I had a "normal" lamba expresion like lamba x:x+6 how does that translate into BLC?

New Main Posts

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Q: Numbers that really get around

Let n be some positive integer greater than 1. Let f(x) be a quadratic polynomial having integer coefficients with absolute value less than or equal to sqrt(n). The domains of all f(x) are the integers with absolute value strictly less than n. Define the function F(n,k) to be the function that t...

isaacg

@PhiNotPi I'm not sure. Here's an example, though. True is defined as the function which takes 2 arguments and returns the first one. False takes two arguments and returns the second one. If .. then .. else is then the function which takes three arguments and returns the first applied to the second applied to the third.

It's explained better here:

Lambda calculus

Lambda calculus (also written as λ-calculus) is a formal system in mathematical logic for expressing computation based on function abstraction and application using variable binding and substitution. First formulated by Alonzo Church to formalize the concept of effective computability, lambda calculus found early successes in the area of computability theory, such as a negative answer to Hilbert's Entscheidungsproblem. Lambda calculus is a conceptually simple universal model of computation (Turing showed in 1937 that Turing machines equaled the lambda calculus in expressiveness). The name derives...

BLC is just a binary encoding with i/o of Lambda Calculus

Zgarb

@PhiNotPi None of the golfing languages I've seen has full lazy evaluation a la Haskell. It can simplify some programs a lot.

isaacg

Yeah, HaskellGolf would be pretty cool

Zgarb

2:59 AM

I've been toying with the idea of doing a golfing language based on Haskell that's even lazier than it, but unfortunately I'm lazy too.

PhiNotPi

Here's how I think multi-dimensional array-list-thingy multiplication would work:

feersum

APL or J have a lot of multidimensional array thingies, if that bothers you

PhiNotPi

[2 3]3* -> [6 9]
[2 3][3]* -> [6]
[3 [4 5]][2 3]* -> [6 [12 15]]

Is this how it normally works?

isaacg

In pyth, the first is *M[2 3)

The second is *V[2 3)[3)

And the third would be *V[3 [4 5))[2 3) if multiplication worked like 1

feersum

I don't get the second one

isaacg

3:04 AM

But Pyth actually does list replication

PhiNotPi

Array multiplication was just a thing I was working on because my previous language, Element, has literally no support for lists or array operations.

feersum

In APL or J I believe all subarrays should be the same length/type rather than a list of duck-typed things

isaacg

Is the second one 6 because 2 * 3 = 6, and then the other 3 is discarded?

PhiNotPi

Yes, like [7 8][9]* -> [63]

On my list of ideas is something called a "stream" variable, inspired by the language Lucid.

feersum

It looks more of a recursive operation on single-dimension arrays

PhiNotPi

3:06 AM

Basically a way to create and manipulate "infinitely" long lists of numbers that are defined by some pattern.

This thing: en.wikipedia.org/wiki/Lucid_(programming_language)

feersum

Haskell has infinite lists

isaacg

But no, I would not call that "how it normally works"

Reto Koradi

@Zgarb Do you think a golfing language based on Haskell concepts could be more compact than the ones we have? Or just cool? I don't really know Haskell. Seen examples, and it looks utterly weird to me.

PhiNotPi

@feersum The "stream" variables idea is basically how Haskell's lists work, as far as I can tell.

isaacg

@RetoKoradi The current golfing languages are similar lengths with dramatically different concepts, inticating that this is the base length for any system using one character for each simple operation / loop

This indicates that HaskellGolf would be similar

I'd guess

Reto Koradi

3:16 AM

@isaacg Spending about 2 minute reading up on Haskell, it somewhat goes along with a thought I had (but not really explored so far). I was thinking about using a stack based paradigm, but delaying the evaluation of values until they are used. No idea if this would hold water. Just one of the things that came up while brainstorming with myself. ;)

isaacg

Neat idea.

PhiNotPi

Has anyone else looked at the Lucid language? en.wikipedia.org/wiki/Lucid_(programming_language)

PhiNotPi

4:08 AM

@isaacg Since PPCG probably contains the majority of Pyth code available anywhere, you can probably do some data gathering to find common sequences of characters, which are things that you could provide more built-ins for.

Reto Koradi

4:19 AM

@PhiNotPi I don't think you can reliably identify "missing" operators by simple analysis of existing answers. Serious golfers may often choose a completely different solution just because it turns out 1 or 2 bytes shorter. So instead of using a sequence of operators to replace the "missing" operator, they may end up writing completely different code.

New Main Posts

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Q: Finding Polynomiality™

f(x) is a quadratic polynomial that is subject to the following conditions, where n is a positive integer. f(x) has integer coefficients, each having absolute value less than or equal to n. The domain of f(x) is the set of integers less than or equal to sqrt(n). Define the "polynomiality" of ...

code-golf math polynomials

isaacg

5:27 AM

@PhiNotPi Yeah, we've done some data analysis of that, but we should really do more. One we've identified is sm

Mitch Schwartz

6:50 AM

@Zgarb you could try burlesque

there's a note that "However, its support for lazyness is limited and does not extend to every command. " but it has infinite lists for example (and i haven't used it much)

Beta Decay

7:35 AM

It's back :D

trichoplax

8:12 AM

@Calvin'sHobbies Good point. Now that you remind me, I did have (unexpressed) concerns about that one at the time, but it was well received. I still have this nagging worry that someone else will ask a question and say "but Calvin's Hobbies asks questions like that", but I guess a question type being difficult to design well shouldn't make it off topic.

Peter Taylor

8:39 AM

@Doorknob Why not just delete it? It's old enough that no-one would lose rep.

@Calvin'sHobbies Yes: one. Going by the offline copy I have, which is from July last year, there are eleven sequences which only have one entry. The first is A058445, so it wouldn't yet affect any users. There are 103 sequences which only have two entries, of which the first is A001220. There were 17361 entries with fewer than 10 entries (about 7%).

Peter Taylor

9:01 AM

@Calvin'sHobbies Off the top of my head, there are some sequences which are actually sets of numbers meeting a criterion where certain numbers are known to be in the set, but it's not known whether there are other numbers smaller than the largest known one which also meet the criterion.

@Sp3000 In CJam: DLosc qi3*2# ; edc would I think be X344./'.-qi=` ; yours would be almost identical; mine ties with DLosc: qimqmo

Sp3000

9:20 AM

@PeterTaylor Oh right, I forgot CJam had rounding...

Peter Taylor

9:41 AM

And I think the clear winner would be user 401, who doesn't post much but was last seen only a month ago, and who could submit the empty program in GolfScript.

Martin Büttner

11:05 AM

@Dennis have you tried Argyle ASCII Art yet?

New Main Posts

12:08 PM

0

Q: Sort multiple array class

I have class named account i am entring information account[0].id=5; account[0].name=roben; Another information account[1].id=4; account[1].name=roz; The problem i wanna sort information, It depends on the id number of the smallest to largest with change name also After sort Index account.id ...

array-manipulation sorting java

Doorknob

12:38 PM

@PeterTaylor Can't just completely get rid of the second-highest-voted question on the entire site—at the very least, it has historical value, not to mention the >100 answers on it.

Dennis

1:11 PM

@MartinBüttner No, not yet.

@Doorknob I say lock it. The question should have been closed in 2014 as well, but 42. It's the very definition of too broad and having it open, unlocked and at the top of the highest voted questions gives the impression that it's acceptable to post questions like this.

(Ironic that we both voted to reopen that question, huh?)

PhiNotPi

1:27 PM

There seems to be some unused single-letter programming language names, like H, U, V or W.

Martin Büttner

2:41 PM

@Dennis I've got 80 bytes, but I'm sure you could manage closer to 60

Dennis

@MartinBüttner Haven't even read it properly yet. I had to figure out why my cop submission worked to make it safe. :P

Martin Büttner

:D

Dennis

I was pretty close to saying I have no idea why this works, but it does!.

Sure learnt a lot of language for your quiz. Both esoteric and the one's of the interpreters. Why can't everybody just use Python or C for their reference implementations?

Martin Büttner

2:59 PM

or Ruby...

or C#...

Optimizer

Eiffel 65 - Blue (Da Ba Dee) (Original Video with subtitles)

►

Dennis

@MartinBüttner Not a big fan of C#. Compiling Retina was uneventful with mono, but not everything is that easy.

Doorknob

Snowman has got to be one of the only esolangs implemented in C++. :P

Which is easy because Makefile.

Martin Büttner

@Doorknob Fission

RubE on Conveyor Belts as well I think

Dennis

~English, StackStacks and ??? also have a C++ implementation.

PhiNotPi

3:24 PM

Is there any language that has a "map-eval" functionality? Let's say that the stack is (1 2 3) and I have an array of code blocks like [{+-} {*+}]. A map-eval function would result in an array like [2+3-1 2*3+1] which is [4 7]

Martin Büttner

3:36 PM

in CJam you could do [{+-}{*+}][1 2 3]f{\:F;~F}

so there's no built-in, but it's not too hard to do

Dennis

4:02 PM

@MartinBüttner Good guess. I'm at 59.

Martin Büttner

see ;)

this is mine, in case you find anything you can borrow to shorten yours: YXb{{_2$+\}*]}q~(*{_2*T+:T\,_ff{='\' ?}f{_W%'\'/er+\' e[}}%:..e>_z,f{Se]}N*_W%N@

Dennis

The first part is already one byte shorter than what I had.

Martin Büttner

yeah I didn't think that was the inefficient bit ;)

Dennis

I generate a string of the appropriate length and rotate it to obtain the others:

0

A: Argyle ASCII Art

CJam, 59 bytes YXbri({_2ew::+\.\}*:,_:|,S*0'\tffm>{_W%'\f/'/f*}%:+zN*_W%N@ Try it online in the CJam interpreter.

Martin Büttner

ah, that's much simpler

Dennis

4:27 PM

Can't find anything else right now. Thanks for the byte!

Do y'all remember the good old days when you just had to look at the avatars to know who was in chat? :P

Doorknob

@Dennis Mine's... pretty recognizable. :P

Dennis

4:54 PM

@Doorknob Yeah, but who are Tails, Snoopy and that kid? :P

Snoopy's a bad example. DLosc isn't really active in chat.

But there are also a turtle and a hash tag. It's all so confusing...

Doorknob

The turtle is actually trichoplax's original avatar.

Dennis

I'll have to take your word for it. I've only started chatting a few months ago.

Doorknob

Wow, seems like you've been around forever ;)

Optimizer

Voiz is shebang, right?

Martin Büttner

yes

Dennis

5:08 PM

Yes, but I think it was -Vioz.

Optimizer

did you confirm using mod tools or memory?

it was Voiz-

Dennis

I asked him.

Optimizer

I remember pinging him, but never starting with a -

always with a V

Martin Büttner

@Optimizer I think it used to say that on their profile

Doorknob

It was Vioz-, I'm pretty sure...

Dennis

5:10 PM

Yes, Vioz-.

Shebang

Yes, Vioz- :)

Dennis

@Vioz-:) If you say so, it has to be correct.

Doorknob

No, he never said his username was "@Vioz-:)Ifyousayso,ithastobecorrect.".

Optimizer

is it @Vioz-:)Ifyousayso,ithastobecorrect.". ?

Doorknob

There was no question mark anywhere in the username either.

Optimizer

5:20 PM

question mark is because i am asking a question

its pretty clear because there's a space before it

Dennis

(Oh lord, what have I started?)

Doorknob

:D

Optimizer

oh, was that too full of spaces? :P

Dennis

Haha.

No golfing languages have dared yet to mess with the spaces. I wonder why.

Doorknob

I'm sure there's at least one counterexample

Alex A.

6:40 PM

@Dennis I think you did a great job on your spaces/tabs challenge. The spec is clear and it seems like an interesting, nontrivial problem. That said, I refuse to participate on principle. :P

Peter Taylor

@Dennis GolfScript documentation does talk explicitly about using space as a variable (and the potential for confusion)

Alex A.

What's your preferred indentation, @Peter?

mine is 3 spaces

Tabs.

Incorrect.

6:42 PM

^

Optimizer

^

Alex A.

@Optimizer @PeterTaylor You both knew this was coming: ಠ_ಠ

Optimizer

I think Peter is not trolling here. he is serious

Alex A.

I know.

BrainSteel

Huh. My username anagrams with Stain Rebel... I'll, uh... be right back...

Alex A.

6:43 PM

Hahaha

I didn't get it

It's silly

still

@BrainSteel Also Beans Tiler, Bear Tinsel, Breast Line, Enter Basil, Sir Tenable

@Optimizer Idk, I don't think there's much to get, it's just silly. One who rebels against stains I guess.

Martin Büttner

meh somehow my mathematica installation is borken. I guess that's as good a reason as any to update it.

Alex A.

6:49 PM

Borken, eh?

Martin Büttner

yes, borken

Dennis

@PeterTaylor Yes, I know. (I've actually used that in a CnR a few weeks ago.) I meant that my challenge, where you have to replace spaces with tabs, has no answers in golfing languages yet.

Optimizer

@MartinBüttner it can't add two integers without JQuery?

Alex A.

@MartinBüttner Are you referring to this?

Dennis

@AlexA. Don't let that hold you back. :( I've participated in the chunky/smooth challenge as well, and I still haven't tasted chunky or smooth PB.

Martin Büttner

6:52 PM

@AlexA. #1 and #3, yes. definitely not #2.

Alex A.

@MartinBüttner Good lord, I didn't scroll down. I didn't realize there was a #2. shudders

Optimizer

it's broken in more than one way

Alex A.

7:04 PM

@Dennis Chunky vs. smooth peanut butter is less polarizing than spaces vs. tabs.

Holy wars have been fought over spaces vs. tabs. (And of course spaces, being objectively superior, won.)

4

New Main Posts

0

Q: feature_importances_ when using random forests in scikit-learn

I am using Random forests in scikit-learn. I used feature_importances_ to see how much each feature is important in prediction goal. But I don't understand what is this score. Googling feature_importances_ says it is the mean decrease impurity. But I'm still confused whether this is the same as m...

random

Optimizer

7:30 PM

@AlexA. I can testify that.

Alex A.

:)

Beta Decay

7:48 PM

Hellooo

What've I missed while I've been gone? :D

Martin Büttner

we're graduating

Beta Decay

Nov 1st?

Martin Büttner

± 6 to 8 weeks

so any time now

Beta Decay

Plus or minus?

Optimizer

you dont know that symbol?

Beta Decay

7:50 PM

So we may have already graduated? :D

Optimizer

plinus

Beta Decay

milus

Alex A.

Don your caps and gowns, boys and girls, it's time for the PPCG graduation ceremony.

3

Peter Taylor

8:08 PM

I've never owned a cap.

And I don't know what I've done with my Geneva bands.

I may have lent them to a cousin for their graduation a few years back.

Alex A.

I rented graduation attire for my high school graduation but I didn't attend the graduation ceremony for my university.

Peter Taylor

I already had a gown for my B.A. graduation, and I bought a hood. (It was ex-rental: the rental company was getting rid of its real fur stock. It only cost twice as much as renting, and since I knew I'd be able to lend it to at least one cousin it made economic sense).

For my M.A. graduation I borrowed my father's gown, which was from a different university but in the same pattern. And I already had the hood.

Optimizer

Is it that big of a deal ?

our university gave that dress to everyone. They posted it to those who did not attend the ceremony

Alex A.

@Optimizer I didn't think so, which is why I didn't go to my ceremony.

(Wow, 5 messages on the starboard. An all-time high for me I think.)

Peter Taylor

It was at my university. If you don't have someone tell the Vice-Chancellor in Latin that you're an upstanding example of integrity, how could you ever be considered worthy of a degree?

Alex A.

8:17 PM

I have no idea what that means.

Who is Chandler Vice and why do you have to speak to him in Latin?

Clearly I am not an upstanding example of integrity. :P

Martin Büttner

that moment when you don't have enough disc space for both the installer and the program you want to install

Alex A.

u_u

What are you trying to install?

Martin Büttner

Mathematica

Alex A.

What's the newest version, out of curiosity? I think I have student edition 9 or 10.

Martin Büttner

I think it's 10.2

(that's the version I'm installing)

I had some space left on my other partition, so I moved the installer there

Alex A.

8:31 PM

Do you have a student version?

Peter Taylor

He's the head honcho. (Actually for the B.A. graduation, at least, it was probably a Pro-Vice-Chancellor, one of his deputies). And the Latin is required by Tradition. Something like praesento vobis hos juvenes quos scio tam moribus quam doctrina idoneos esse ad assequendos titulum baccalaurei in artibus; idque tibi fide mea praesto totique Academiae. Serious stuff.

The guy who had to do it said that keeping a straight face was very hard.

Martin Büttner

@AlexA. yes. for some reason my licence has been extended until October next year... I'm not complaining though :D

Alex A.

When licensing student software that expires when you graduate I always tell them that I'll be graduating in like 2030.

If it's a drop down I just go to the maximum year for graduation. No craps are given by me.

@PeterTaylor I can imagine. :P

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