The h Bar

(::shrugs::) I asked for several books including a QM book, Apostol's Calculus, etc...I'm told by my grandparents that there is more coming, so who knows what that might entail.

(my grandparents live a ways away, so it seems the mail had some issues conveying the various items here)

0celo7

I must say, getting an intro calc book and an advanced QM book at the `same' time is strange.

heather

the QM book I requested was Shankar...I was told that was a good introductory book if you knew calculus, and I was also told Apostol was a good calculus book.

0celo7

You need to know more than calculus for Shankar

And "calculus" refers to calc 3 or more

Also differential equations

user116211

You need Hoffman for Linear Algebra too.

heather

2:22 PM

I know you need to know linear algebra, but I've already taught myself a decent portion of that.

0celo7

You've worked through it?

Do you know what a basis is?

heather

not Hoffman, another book

user116211

@0celo7, I took a peculiar exam today.

heather

@0celo7, yes, I know what a basis is

and what eigenvalues/eigenvectors are

0celo7

@heather Gram-Schmidt?

user116211

2:23 PM

Two papers.

heather

@0celo7, I'd have to check my textbook again for that one, one moment

user116211

One on Ring Theory.

user116211

Other on Mechanics.

0celo7

Why do you capitalize those words?

user116211

@0celo7 Why would she know that now?

0celo7

2:23 PM

@MAFIA36790 She's smarter than us.

ACuriousMind

@0celo7 That is not the proper use of comments. Chat conversations in comments will be deleted.

heather

@0celo7, the Gram-Schmidt Orthonormalization Process?

It's in the book I've got...I could probably figure it out.

user116211

Anyways, prof asked me to show Euler Lagrange Equation without using Calculus of Variations.

user116211

Lanczos saved me.

heather

@0celo7, and in terms of calculus, I asked for Apostol I and Apostol II - is that going to be enough?

user116211

2:26 PM

@heather For calc III? No.

0celo7

@ACuriousMind For fuck's sake.

user116211

@0celo7 SE is not forum.

0celo7

@JohnDuffield See?

heather

@MAFIA36790, how about calc II or PDEs?

0celo7

@MAFIA36790 More like North Korea.

user116211

2:27 PM

JD can't talk :(

0celo7

@MAFIA36790 huh?

user116211

@heather PDE? Well, a good intro, I would say.

user116211

@0celo7 yes.

0celo7

what kind of first semester exam is that?

user116211

I don't know.

user228700

2:27 PM

@heather Hi :-) I'm OK, thanks! What about u? How's the self teaching going?

heather

@MAFIA36790, okay. So then how much of a gap between what I need to know and Apostol I and II is there?

user116211

@heather Well, both the books are good for beginners; there are good exercise. Complete the two totally first. For multi-variable, you would need other books, though.

heather

@Kaumudi, pretty good...my grandparents told me there's another package coming, so I get a two day birthday instead of one =P My mom was laughing so hard because I basically just asked for textbooks.

user116211

@0celo7 This exam was 2nd terminal; 1st sem exam is one month away.

user116211

Still, it was not a standard query.

0celo7

2:29 PM

What does that even mean?

heather

@MAFIA36790, darn...okay. For some reason I thought the second went into multivariable calc. Ah, well, it'll be a good start.

user116211

I was bit surprised.

0celo7

How are you supposed to do that? d'Alembert principle or something?

user116211

@0celo7 Just like how Euler did it.

user228700

@heather Omg :-D Awesome! What dyour friends think about you teaching yourself all this advanced stuff?

0celo7

2:30 PM

I don't speak German, I don't know how he did it.

heather

@Kaumudi, they think I'm a nerd, obviously, which I am, but they're nerds too, so =P

user116211

I can give you the snapshot of Lanczos.

user228700

@heather :-) Well, have fun! And best of luck-I'm sure u'll need some lol :-P

heather

@Kaumudi, no kidding =D How's the learning going for you?

user116211

@0celo7 Hey, you know German(?) .

0celo7

2:33 PM

@MAFIA36790 Maybe...my memory is pretty bad.

user228700

It's going a bit slowly, tbh. Gots to pick up speed if I have any intention of completing my syllabus by December.

user116211

Oct 11 at 1:53, by 0celo7

I speak German fluently

heather

@Kaumudi, what is in your syllabus?

user116211

@0celo7 Don't respond; this is not what comment is meant for. In any case, they will be deleted.

0celo7

@MAFIA36790 It's not on comments. @ACuriousMind can search as much as he wants.

ACuriousMind

2:35 PM

@0celo7 Stop using the chat to try and communicate to a chat-banned user.

0celo7

Sigh. John told me I should stop before I get into big trouble.

user228700

@heather Oh, I don't really know how to summarize it precisely, but I have a lot of Newtonian Mechanics, geometrical and wave optics, thermodynamics, and "modern physics" (which basically encompasses stuff like the particle nature of light, nuclear reactions and all) and that's just physics :-P

heather

@Kaumudi, wow, that's awesome!!! What are you currently on?

ACuriousMind

@heather What I said goes for everyone.

0celo7

wtf

heather

2:37 PM

@ACuriousMind, my apologies. I'll stop.

ACuriousMind

@heather thanks

heather

@0celo7, it's not a big deal! ACM has a point.

0celo7

No, he doesn't.

heather

Yes, he does, and so this doesn't change into some whacky argument, do you want to talk about analysis?

user228700

Oops, left out electrodynamics!

heather

2:38 PM

@Kaumudi, can't forget the electrodynamics! =P

0celo7

@heather no, I'm in a bad mood

user228700

:-P Yeah, I'm doing electrodynamics and "modern physics" now.

user228700

I have a lot of crap left in Chemistry and Math, sigh.

heather

@0celo7, okay =)

@Kaumudi, what are you doing for math?

user228700

God, I hope I can stop procrastinating so much.

user116211

2:39 PM

@0celo7 Nazis? This is a bit extreme.

heather

@Kaumudi, I procrastinate like crazy.

user116211

Reminds me of Wolfenstein.

0celo7

@MAFIA36790 Definitely not.

user228700

@heather Oh, tell me about it >.<

user228700

I'm not actually that horrible :-P Some days suck, like this one. Hm, Math...

user116211

2:41 PM

@0celo7 Listen to some good music.

0celo7

I'm in a bad mood because of ACM, no music can fix that.

heather

@Kaumudi, I've made myself give up fiction books for the most part because they make me procrastinate

user116211

ACM talked just ;/

heather

@0celo7, oh, come on, how about Imagine Dragons?

user228700

@heather Omg, NOOOO!

heather

2:42 PM

@Kaumudi, what, Imagine Dragons or absence of fiction?

0celo7

Click the arrow to see which post she's responding to.

user228700

@heather Absence of fiction, of course!

user228700

Yes, ^

0celo7

@heather Don't like them.

heather

@Kaumudi, well, I still read some, very occasionally but for the most part nonfiction is my best friend =D

user116211

2:43 PM

Afternoon @JohnRennie.

user228700

@0celo7 The Mountain Goats?

heather

@0celo7, how about Young the Giant? Brad Sucks? Miike Snow?

Bernard Meurer

What up

0celo7

Don't know any of those people

heather

@BernardMeurer, hello

Bernard Meurer

2:44 PM

@heather Don't fickle with @0celo7 musical taste, you will only find frustration there

heather

@0celo7, then you should start listening to them

0celo7

@BernardMeurer ???

user228700

@heather Whatever works for u, but there is a way around procrastination :-P How does it make u procrastinate tho?

John Rennie

→ 1 message moved to Trash

heather

@BernardMeurer, speaking of frustration, could you perhaps help me a bit with Pseudocode for Turing Machines?

Bernard Meurer

2:45 PM

@heather Sure thing :)

heather

@Kaumudi, I start reading a fiction book, I get sucked in, I ignore the outside world and then I look up and it is 2 hrs later =P

0celo7

@JohnRennie Stop deleting stuff. What the hell is wrong with you people?

John Rennie

I deleted an offensive comment

user228700

@0celo7 You should like, get off the internet. Till u calm down, I mean.

heather

@BernardMeurer, basically, I don't understand the restrictions on pseudocode, specifically the part about recursive function calls not being allowed.

Bernard Meurer

2:45 PM

Let me:
1. Change from my PJs
2. Get some Cheese
3. Get some ham
4. Get some beer
5. Get some water
And i'll be ready

heather

@BernardMeurer, sounds good =P

0celo7

@Kaumudi I'm perfectly calm. It's possible to be perfectly calm and in a blind rage simultaneously.

heather

Perhaps I'll make myself some peanut butter oatmeal...

user228700

@0celo7 I highly suspect that. "Till ur blind rage subsides" then.

heather

@0celo7, blind rage + internet = not good things

0celo7

2:47 PM

@Kaumudi Consider it subsided.

I am now moderately enraged.

user228700

@heather U're wiser than most YouTube commenters :-P

user228700

@heather This was my life in middle school :-P It was a great life.

user228700

@heather: What kind of fiction dyou read? (Or, you used to read :-P)

Bernard Meurer

@JohnRennie Is it bad that I've been having beer for breakfast?

user228700

Speaking of fiction, @MAFIA36790: Dyou read any fiction at all? I've been re-reading "The Catcher in the Rye" before bed and somehow, I feel like it's a book u might like. I don't even know u bit still :-P

user116211

2:51 PM

@BernardMeurer WTH ;/ why?

Bernard Meurer

@MAFIA36790 It tastes good dawg

0celo7

you're sick

user116211

@Kaumudi I read mostly non-fiction.

Bernard Meurer

(It's also cheaper than water)

user116211

@BernardMeurer Coffee tastes good too.

user228700

2:52 PM

@MAFIA36790 Figured as much :-P

Yashas Samaga

are all adiabatic processes involving ideal gas reversible?

user228700

@BernardMeurer That can't be true. Really?

Bernard Meurer

@Kaumudi I just got up

I'm having one right now

@heather I'm ready

0celo7

umm

it's like 2 oclock

heather

@BernardMeurer, okay

Bernard Meurer

2:53 PM

@0celo7 Yes

heather

@Kaumudi, just about anything...I especially like Rick Riordan's mythology in today's world books

Just not romance or horror

Bernard Meurer

amzn.com/0486229491

@heather Read that one

heather

@BernardMeurer, okay, putting it on my list

user228700

@heather Ah, OK :-) I've never had the chance to read any of his books. Anyhoo, enjoy your Math discussion! If I stick around for any longer, I'm going to kill myself :-P

heather

@Kaumudi, have a good day, then, goodbye =D

user228700

2:56 PM

My day's almost over-it's 8:30 PM here :-P

heather

good night then =)

user228700

You have a good day :-) Bye!

heather

@BernardMeurer, okay. So my main thing with the pseudocode part is the restrictions:

1. The program has a finite, predefined number of variables.
2. Each variable can take only a finite, predefined set of possible values.
3. Recursive function calls are not allowed.

especially the third one...does that mean stuff like for and while statements are not allowed?

0celo7

@BernardMeurer I programmed a roomba to go around a figure 8

Bernard Meurer

@heather Did you get through the examples alright?

@0celo7 Sweet!

ACuriousMind

2:58 PM

@heather Iteration is not recursion (although they are often related)

heather

@BernardMeurer, I think so, yeah. It made sense, so that's good.

@ACuriousMind, I probably don't understand the difference then =)

Bernard Meurer

@heather First of all, recursion vs. iteration

While and for loops and things of the kind are iterative

We won't get deep into that now

A recursive structure is one where a function calls itself

heather

oh! I didn't realize that.

Bernard Meurer

My favorite example, the ackermann function

heather

okay

how does that call itself?

Bernard Meurer

3:01 PM

def foo(a,b):
    a = foo(b,a)
    b = foo(a,b)
    return(a,b)

0celo7

@ACuriousMind Is the collection of all finite subsets of a countable set countable?

heather

@BernardMeurer, and the Ackermann function calls itself, right.

0celo7

@ACuriousMind Never mind (I know you're ignoring me anyway)

Bernard Meurer

def ack2(M, N):
    if M == 0:
        return N + 1
    elif N == 0:
        return ack2(M - 1, 1)
    else:
        return ack2(M - 1, ack2(M, N - 1))

@heather Ackermann function in Python

ACuriousMind

@0celo7 Lookee here (The idea works for any countable set, not just $\mathbb{N}$)

0celo7

3:06 PM

@ACuriousMind I found a proof on Proof Wiki

It's linked somewhere in the comments

heather

@BernardMeurer, okay.

Bernard Meurer

@heather Can you see why it's recursive? How it calls itself

heather

@BernardMeurer, yeah, that makes sense now.

Bernard Meurer

Generally you want to avoid recursion (hot topic, many people think differently, this is opinion)

heather

So then, going back to restrictions, #1 and #2 are just saying that the number of variables has to be finite, and the number of values for those variables is finite?

Bernard Meurer

3:11 PM

Because it's easier to screw up and generate an unbounded recursion that goes back in time and kills your grandfather so you're never born

heather

lol

yes, I don't want to kill my grandfather with a recursion =D

Bernard Meurer

@heather It's just saying the program has a finite number of variables

And that they were set beforehand

John Rennie

@BernardMeurer recursion can get inefficient because of all those function calls, and it can run out of stack space if it goes too deep. But recursion is still an exceedingly valuable technique in the right circumstances.

Bernard Meurer

@JohnRennie That's why I said "generally"

@heather Read what John said, he's very much right

@JohnRennie I try to avoid recursion as much as I can, iteration is faster and less prone to explosions

I even made an iterative implementation of Ackermann's function

ACuriousMind

Recalling your kitchen adventures, everything is prone to explosions when you're involved ;)

Bernard Meurer

3:17 PM

@ACuriousMind Lol, you do have a point there

heather

Okay, that makes sense then. Thank you! I'll keep reading and see where I get stuck next =P

0celo7

I'm stupid

Can I just give up

Bernard Meurer

Who cares about topology? (inscribed rectangle problem)

►

@0celo7 What up?

heather

Oh, I love 3Blue1Brown!

Their linear algebra series is excellent.

0celo7

@BernardMeurer topology homework too hard

@ACuriousMind Imgur just emailed me about Caturday...

Bernard Meurer

3:31 PM

I just watched all of Rick and Morty

I need a new show

0celo7

I had a pretty good pizza last night

Bernard Meurer

@0celo7 The slovenian made me pizza the other night

Qmechanic

-1

Q: What does $w_{\tau}=-w_x$ mean?

Problem and solution given at http://exir.ru/1/resh/1_106.htm A small washer put on the inclined plane, which makes an angle α with the horizon, and reported the initial velocity v 0 (Fig. 1.27). Find the dependence of the speed of the puck angle φ, if the coefficient of friction k = tg α and...

Homework-like? Revoke bounty?

0celo7

Bacon, Ham, Spinach, Feta

heather

^sounds delicious

I'm making pancakes right now =D

0celo7

3:33 PM

@Qmechanic You know Russian?

user116211

@BernardMeurer The Flash.

Bernard Meurer

@MAFIA36790 Watched it, hated it

ACuriousMind

@0celo7 So? Nice of them to remind you, no? ;)

Bernard Meurer

@0celo7 How's the dog?

0celo7

@ACuriousMind Remind me that I haven't seen my son in 5 months?

Bernard Meurer

3:34 PM

@0celo7 Hm? You were home not so long ago

0celo7

Before summer

Back in May

ACuriousMind

@BernardMeurer Firefly.

0celo7

@BernardMeurer Alive and well

Bernard Meurer

@ACuriousMind Got cancelled, it will only break my heart

user116211

@BernardMeurer Arrow.

0celo7

3:35 PM

He just decided to almost die for no reason, and is now back to his old self

Bernard Meurer

@MAFIA36790 Arrow was too stupid

0celo7

Stupid dog

user116211

WTH ;/

ACuriousMind

@BernardMeurer Still what got made were some good hours of television.

user116211

Legends of Tomorrow.

John Rennie

3:35 PM

@BernardMeurer since we're talking about pizza ...

0celo7

@BernardMeurer wtf

@JohnRennie wtf

John Rennie

I've just finished this.

user116211

@JohnRennie ;(

Bernard Meurer

@MAFIA36790 Will check it out

0celo7

Brits should stick to disgusting meat dishes ;(

or Curry

Bernard Meurer

3:36 PM

@JohnRennie That's one fine pizza right there

John Rennie

Spicy chicken, peppers, chilli, onion, everything really.

Bernard Meurer

I gotta go to Chester

John Rennie

Actually, that's my second one. I've just eaten two of those :-)

0celo7

So are you coming to my place for Thanksgiving?

Or are you going to Houston

Bernard Meurer

@0celo7 Neither, no money

heather

3:37 PM

man, these pancakes are looking good - they're chocolate chip, too =D

Bernard Meurer

@JohnRennie HOW ARE YOU SKINNY

0celo7

I'm literally going to die if I don't eat

heather

plus, there's the sidebonus on munching on chocolate chips as you make them

ACuriousMind

now I'm hungry

John Rennie

@BernardMeurer tapeworms

2

0celo7

3:38 PM

Fuck, I need some of those

The biology dept probably has one

Bernard Meurer

I need some tapeworms too

0celo7

shut up you're skinny

user116211

@0celo7 Why?

0celo7

I'm 400 lbs dude

heather

hmm...let's see, I'll keep a few plain for butter and syrup

user116211

3:39 PM

No worm talks, please.

heather

@0celo7, I can't say I quite believe that, but alright

0celo7

ask Bernardo

Wait, I forgot the conversion

It's 200

Bernard Meurer

@heather He's a giant. Last time he hugged his sister it took us 3 weeks to find her

user116211

@BernardMeurer Horror!

heather

now I really don't believe you =)

0celo7

3:41 PM

I'm twice her size

Bernard Meurer

@heather Ask Rebecca

0celo7

That's not even a lie

heather

okay, okay, nevermind

Bernard Meurer

@0celo7 Lies

0celo7

She's pure muscle

Bernard Meurer

3:44 PM

She's stronger than me, definitely

@0celo7 Dude, Ron gives me shit for liking skinny girls

Secret

But first, we need to understand what makes a square, a square:

Inscribed square problem

The inscribed square problem, also known as the square peg problem or the Toeplitz' conjecture, is an unsolved question in geometry: Does every plane simple closed curve contain all four vertices of some square? This is known to be true if the curve is convex or piecewise smooth and in other special cases. The problem was proposed by Otto Toeplitz in 1911. Some early positive results were obtained by Arnold Emch and Lev Schnirelmann. As of 2015, the general case remains open. == Problem statementEdit == Let C be a Jordan curve. A polygon P is inscribed in C if all vertices of P belong to C. The...

heather

@BernardMeurer, I watched the video

it was fabulous

Bernard Meurer

@heather It is pretty cool

heather

and really interesting, too

0celo7

@BernardMeurer I think he thought I was gay until I showed up with Rebecca

John Rennie

3:48 PM

Maths for halloween:

3

Bernard Meurer

@0celo7 He was very happy you got Reb, and kind of curious about what goes in that girl's mind

Secret

If the moebius strip encodes the structure of all the midpoints, that means for the square we need to induce some kind of bilinear form in order to encode the angles between the segments

heather

@JohnRennie, lol

0celo7

@BernardMeurer Hmm

Bernard Meurer

@heather Did you do that this halloween?

heather

3:50 PM

@BernardMeurer, no, but I know what I'm doing next year =P

Bernard Meurer

@heather Lol, dress as an HP-35S if you do, it's the best calculator

0celo7

Reminds me

@BernardMeurer bob is insane

Bernard Meurer

HP 35s

The HP 35s (F2215A) is the latest in Hewlett-Packard's long line of non-graphing programmable scientific calculators. Although it is a successor to the HP 33s, it was introduced to commemorate the 35th anniversary of the HP-35, Hewlett-Packard's first pocket calculator (and the world's first pocket scientific calculator). == Features == The HP 35s uses either Reverse Polish Notation (RPN) or algebraic infix notation as input. Other features of the HP 35s include: Two-line alphanumeric LCD Over 800 memory registers (26 directly labelled) Scientific and statistical functions Operation in decimal...

@0celo7 Why?

heather

@BernardMeurer, I'll keep that in mind...or how about the TI-89? That's the one I have; it's a pretty good calculator.

0celo7

He didn't think one of my gfs in HS was impressive enough, so he made shit up about her when talking to his brother

Bernard Meurer

3:52 PM

@heather TI's are good, but they all look hideous(i.e. TI 30XS). HP's aren't as good generally, but they have superb build quality and design

heather

They don't look hideous!

0celo7

Kevin hates TI

Bernard Meurer

One sexy piece of calculator

heather

TI-89 series

The TI-89 and the TI-89 Titanium are graphing calculators developed by Texas Instruments (TI). They are differentiated from most other TI graphing calculators by their computer algebra system, which allows symbolic manipulation of algebraic expressions—equations can be solved in terms of variables, whereas the TI-83/84 series can only give a numeric result. == TI-89 == The TI-89 is a graphing calculator developed by Texas Instruments in 1998. The unit features a 160×100 pixel resolution LCD screen and a large amount of flash memory, and includes TI's Advanced Mathematics Software. The TI-89 is...

Bernard Meurer

@0celo7 I only like the Nspire line

heather

3:53 PM

That is not hideous

That is awesome

0celo7

Bob too

Nspire CX CAS might be the greatest piece of technology on this earth

Bernard Meurer

@heather Too many colours, it's for kids

0celo7

Why can't my $1000 phone do a third of the stuff that thing can :(

Bernard Meurer

LOOK AT DAT HP

@0celo7 The Nspire CX CAS runs doom on linux

enough said

heather

@BernardMeurer, I am a kid! (Well, teenager but whatever) and besides colors make it styling

they give it snazzy-ness.

0celo7

3:55 PM

My phone runs San Andreas

Bernard Meurer

@heather Depends on how they're used, that colour palette over there, no good

@0celo7 So does any potato PC nowadays

heather

gray and blue and black? That's a perfectly good color palette!

0celo7

I just realized

I can't play GTA and use the headphones at the same time

Bernard Meurer

@heather And yellow and purple?

Also the tones they picked are all wrong

heather

@BernardMeurer, I'm going to ask my mom to get a few potatoes so I can try making a computer out of it =P

Bernard Meurer

3:56 PM

and the materials too, the buttons should be solid plastic, not rubber

heather

@BernardMeurer, hey, the yellow and purple makes it pop. And the tones aren't all wrong. Besides, my calculator can graph and yours can't =P

The buttons are plastic, not rubber.

Bernard Meurer

@heather This reminds me, did you get an RPi?

@heather Well, they look rubbery

0celo7

@BernardMeurer does your CX get scratched really easily?

The screen I mean

heather

@BernardMeurer, raspberry pi...I still need to ask my dad. I'm waiting for when he's a. not busy b. in a really good mood

0celo7

Mines got a good gouge

Bernard Meurer

3:57 PM

@0celo7 No scratches on mine I think, let me check

ACuriousMind

What's bad about rubbery buttons?

heather

But anyway, I'll ask him soon.

@ACuriousMind, rubbery buttons feel weird.

Kyle Kanos

@ACuriousMind Not enough plastic

Bernard Meurer

@0celo7 Nope, no scratches

0celo7

@KyleKanos prove you are who you say you are

Bernard Meurer

3:58 PM

@ACuriousMind less tactile feedback, so iyou make more mistakes

ACuriousMind

I think I'm dreaming, for a minute I imagined @KyleKanos came in

@0celo7 Shut up ryan

@KyleKanos Kyle!

Hi all

@0celo7 Lol, you got wasted Ryan

ACuriousMind

3:59 PM

@KyleKanos Hey, how are you?

Kyle Kanos

@ACuriousMind This happens like...monthly. Maybe?

heather

@KyleKanos, hello (::awestruck::) I've never seen you around.

Kyle Kanos

@ACuriousMind Doing well. Just cooking lunch for the kids. Yourself

Bernard Meurer

@KyleKanos I made a good joke about OpenMP the other day, no one got it :(

@KyleKanos Can I be your kid real quick? I'm hungry

Kyle Kanos

@heather Because I kinda quit the site b/c I don't have time between the job, kids &, most importantly, the wife

Bernard Meurer

3:59 PM

I swear I won't ask for college tuition

Kyle Kanos

@BernardMeurer Link? I can laugh at it for you

Transcript for