Mathematics - 2017-08-05 (page 2 of 4)

user84215

09:10

Can any one delete comments on a post?

Jasper Loy

Yes, moderators can delete anything.

The poster of the comments can also delete his own comments.

You can also edit your own comments within a short period of time only.

I am not referring to your meta posts, but the votes on this site are not meant to make much sense in general.

You also don't need to care too much about what others say about you here.

So don't be too upset about the reception of your meta posts, that's all I wanna say @aminliverpool

user84215

My last five comments on a post have been deleted. How can I complain about it?

Jasper Loy

Which comments on what post?

user84215

On this post:

user84215

-23

Q: How can we create a free university within MSE?

I have a new idea. Let us construct a university in MSE. Like other universities it would have classes (MSE chat rooms), staffs (professors, directors, president, ...), research groups and etc. We would also have Bachelor and PhD programs in it and give graduated students Bachelor and PhD degree...

Jasper Loy

09:15

Maybe someone flagged them as inappropriate?

user84215

How can I complain about it?

Jasper Loy

You can raise the issue once again on meta, stating exactly which comments were deleted, and asking why, if you feel they were not inappropriate.

And I really think this is a bad idea, the free university within MSE.

usukidoll

those downvotes though...ouch

Jasper Loy

Sure, you can have free universities in the world, which is already in several parts of the world, just a small fee in some countries, but not in MSE, because like I said MSE is nothing but a simple question and answer site, and the chat, of course.

It's not a novel idea that is scorned by people in this case, to me. It's just something that cannot work, something that is suggested on the wrong platform. Sure build free universities, but not on MSE, full stop.

user84215

What if the moderators themselves behave unfairly? How can I complain of them?

usukidoll

09:23

ehhhhhhh

Jasper Loy

I have already told you to raise a meta post @aminliverpool.

And really it is a small thing for people to behave unfairly, not that this is the case or not, but it happens almost every day in real life!

This is an unfair world where there is unfair treatment everywhere anyway!

It is so in real life, and it is so online.

All you have to ask yourself is what you wanna do about it with the time that is given to you, something Gandalf said in the Lord of the Rings.

user84215

I think we should not allow them to do whatever they want.

Jasper Loy

Hi @usukidoll I see you here after so many years, LOL. I hope you are fine!

usukidoll

oh thanks xD

I completed my undergraduate Math studies :p

s.harp

09:45

@aminliverpool chat.stackexchange.com/rooms/20352/math-mods-office

user84215

@s.harp Can I complain of the moderators themselves there?

s.harp

Moderators are people, you can ask them why they did things and the will explain it to you

taking the position that you are persecuted or unfairly treated will not get you far in life, also not here

7

usukidoll

preach

Jasper Loy

10:07

@s.harp Though very often, one really is treated unfairly, just to add, and the people who are treated unfairly, well, they don't get very far in life anyway, but that's another issue altogether.

Secret

[Random]

The following algebraic structure is inspired from a facebook bug that caused it to unable to scroll back to the previous day:

Consider the following nonassociative structure:

Let $n$ be some element

Then we have recursively $(n)+1 < (n+1)$

It should be note that $1+(n)=(1+n)=(n+1)$ as long $n > m$

Now, when $n > m$ the following will happen

while $(n)+1 < (n+1)$ even when $n > m$

$1 + (n) = (1+n)$ for all $n > m$ but $(1+n) < m$ for all $n > m$

In words, it means that you are free to scroll back to some hours ago, and this is reversible

However, at the mth hour post, the bug occured which despite you can move from the (m-1)th post to the mth post, attempt to move from the mth post back to (m-1)th will give you different posts which is always later than the (m-1)th post choronologically speaking

So at the point m, scrolling is one way, you can move from m-1 to m, but you can move indefinitely far back from m but never reach m-1

(NB the above demonstrate how I can turn a lot of rants into some legitimate discussion by making the rant concrete)

Secret

10:28

For a video game example:

Endless Stairs 10 Hours - Super Mario 64

►

Geometrically, the space modelled by the action of the above algebraic structure on some poset will look like this:

This is even worse than the endless stairs because once you decided to turn around, it will take you the distance you have tried to travel up to get back

The above can also be represented as follows, which is related to the semigroup action non hausedoff topology that Typhon first raised and is a phenomenon very common in the gaming world where surfaces are rendered only on one side

7

Q: I would like help identifying the rigorous classification of this 'surface' geometry based on my interpretation of 3D models.

I want to try and identify a geometric structure I thought up while doing some weird stuff with making things walk on the surface of a 3D model and trying to incorporate backface culling into the surface geometry itself. See, in computer graphics each side of a polygon or triangle are considered ...

geometry 3d surfaces computational-geometry paradoxes

Here, you are free to walk from the left to the right passing the red surface. However, if you walk backwards, you will be forced to walk onto the red surface, and never get back to the gray surface on the left

Antichamber and dozens of Escher type geometry games make heavy uses of this geometry to implement one-way passages

We can also take this geometry even further to implement a very scary trap:

user84215

10:52

Please see my new post:

user84215

-8

Q: We are the 99 % , now in the MSE

I have posted the following two posts in the Meta MSE: How can we create a free university within MSE? and Are downvoting and upvoting performed fairly I saw that in less than one day, they were attacked by flood of down votes. And some users with high reputations put them on hold as "off-top...

discussion meta soft-question stackexchange advice

usukidoll

facedesk

Secret

usukidoll

Does anyone know what Topology is about?

Secret

This topology has a very pathological fractal like property that once you are inside, you can never get out, no matter which direction you move

Suppose you are on one of the red surfaces and you decided to turn back after realising your mistake. Then sorry, you cannot since at any moment you decided to turn back, you will be sent to another surface which will take an eternity to walk through it, now you regret and decided to turn back, you are then once again sent into another surface

usukidoll

10:55

will I get sent from the red space to the blue space?

Secret

So the result is you can only move forward, and you will spend an eternity trapped in such complex

@usukidoll Yes, as soon you decided to turn back

usukidoll

ahh

so if I go forward I'll remain in the red space?

Secret

yes, but you will never escape because it extends to infinity

usukidoll

I know it's a never ending red surface road

so if I was on a red surface turning back then I'm stuck on a blue surface that never ends

lose-lose situation o-o

Secret

yes (and what is not shown is that the red-blue surface structure will keep on repeating down indefinitely, so for the nth surface when you decided to sent back, you will get sent to the n+1th surface)

(luckily, no games think of such scary and boring trap)

I am not sure how one will wrote this mathematically, cause being one-sided surfaces that only exists in gaming design, while it does look like train track topology, as the MSE answer have described, it is produced by a semigroup action. But I suspect if the first iteration is $S_0$, then the whole surface is described by $\bigcup_i^{\infty} S_i$

Now, for the interesting bit. Most games use a finite version of these "one way topologies" to implement things like nonlinear mazes, such that one has to take a certain sequence of directions in order to pass through them, else sent back to the start. Antichamber has one example, but so are many other games. In gaming, we build these structures by using teleportation points such that when the player chaarcter reach those points, they are being transported to a duplicated room which reflect the

set of paths that are avaiable to transverse at that point

Antichamber EP 4 - Green Maze

►

Jasper Loy

11:08

@usukidoll It's a good idea to read Wikipedia for first overviews of a subject, including topology.

Secret

O, almost forgot, suppose your physical space in you game only consists of the gray road. That means, all your movement on the colored spaces will be projected onto the gray space, then what will be seen is as follows:

Moving forward, you will transverse the gray space in uniform steps, but once you decided to move back, you will found even though to you you are talking uniform steps near point m, to others they will see you moving slower and slower, until you are effectively staying put in one point despite they can see you actually walking

Things get even worse when you are in the blue space. Your friends will be seeing you walking but heading nowhere, because your position in the blue space will be projected to where the asymptote of the red space is, which then projects onto the gray space

But we can make the scenario less hopeless and more interesting as follows:

What if your friend decided to give you a push?

Many possible outcomes can happen depending on how this is implemented.

One possibility is that since all actions will be reflected to all the colored spaces at that point, your friend can actually push you out of being trapped in the colored spaces since the point immediately next to it as seen in the gray space has no counterpart in the colored spaces

Perturbative

12:17

@usukidoll Topology is about dank stuff

usukidoll

<.<

The Raiders of Las Vegas

>.>

usukidoll

<.<

The Raiders of Las Vegas

>.>

usukidoll

<.<

Perturbative

12:22

^.^

The Raiders of Las Vegas

^_^

Secret

¬_¬

The Raiders of Las Vegas

-_-

Astyx

v.v

The Raiders of Las Vegas

>8(

Secret

12:26

@_@

SteamyRoot

( ͡° ͜ʖ ͡°)

BAYMAX

(w..w)

Secret

$$\epsilon_{( ͡° ͜ʖ ͡°)}\!\!\!\!\!\!\!\omega$$

Perturbative

(╯°□°）╯︵ ┻━┻

The Raiders of Las Vegas

in The Periodic Table, 23 hours ago, by Chemobot

SteamyRoot

12:35

ಠ_ಠ

Astyx

This has gone too far

usukidoll

whoa

emoticons took over

Secret

$$(╯°□°）╯︵ ┻━┻^{(╯°□°）╯︵ ┻━┻ ^{(╯°□°）╯︵ ┻━┻ ^{(╯°□°）╯︵ ┻━┻ ^{(╯°□°）╯︵ ┻━┻ ^{\cdots}}}}}$$

usukidoll

btw the emoji movie sucks

BAYMAX

there is a movie on emoji..

usukidoll

12:40

yeah it was released

and it was eh

BAYMAX

not nice?

hm

Perturbative

There was a movie on pixels

Astyx

Both seemed terrible

I watched neither

user84215

Please see my new post:

user84215

-12

Q: We are the 99 % , now in the MSE [not duplicate]

I have posted the following two posts in the Meta MSE: How can we create a free university within MSE? and Are downvoting and upvoting performed fairly I saw that in less than one day, they were attacked by flood of down votes. And some users with high reputations put them on hold as "off-top...

discussion meta soft-question stackexchange advice

usukidoll

12:50

come onnnnnnnnnnnnnnnnnnnnn

Jasper Loy

Oh well, I am a little tired of all this ranting now.

I don't see what the problem is @aminliverpool.

What are you trying to achieve with all these posts, exactly?

4

user84215

good question

Secret

Prepare for chat explosion:

Jasper Loy

@usukidoll (removed), ROFLMAO

usukidoll

O

Secret

12:57

in 3

usukidoll

oops cuzzzz I don't wanna get #reported by an attentionnnn ..........

Secret

2

1.5

usukidoll

and it's not seeker or snitch from Harry POtter

Secret

1.25

usukidoll

damn it I was gonna type something but I forgot

Jasper Loy

12:58

I decided to ping you @aminliverpool because I did not want to ignore you.

Secret

1.0

Countdown terminated until further notice

usukidoll

now I know. Honestly making those postings at MSE will only screw your rep further and you're just wasting time and energy on petty stuff. Downvotes mean that the posts aren't that contributing and are very irrelevant as Peppa Pig

Jasper Loy

Maybe think about what you want happen on this site before posting anything again @aminliverpool.

Perturbative

@usukidoll I miss Peppa

Jasper Loy

Guys, look at the star wall, ROFLMAO.

usukidoll

13:01

where?

Perturbative

We famous now

Jasper Loy

On the right, but maybe things look different if you are on mobile.

usukidoll

this? prntscr.com/g4ovvx

user84215

We should not be indifferent about these issues.

Jasper Loy

Yes, I starred the smilies.

usukidoll

13:02

xD

UGH MOVE ON WITH YO' LYFE

it's like those annoying musical DOT ly things

Jasper Loy

@aminliverpool Indifferent about what? People come here to ask and answer questions about math, so what is the problem?

2

user84215

The problem is some users may ignore morality.

Jasper Loy

OMG, morality?

usukidoll

D:

Jasper Loy

Now you are just making shit up.

usukidoll

13:04

omg call the Waaaaaaahhhhhhhhhhmulance

oy I just thought of something.

I think that user was the director of that sweatshirt song

Jasper Loy

@usukidoll I love Jacob Sartorius!

usukidoll

O_____________________________________________O

DEAR LAWD

Jasper Loy

@aminliverpool Seriously, I think you are taking some things too seriously...

Secret

It seems playgrounds like to use polytopes for monkey climbers

user84215

They are serious.

Jasper Loy

13:07

@aminliverpool The matter is very simple. People here downvote or close posts they don't like, end of story. Not an issue of morality at all. And remember this site is for math questions primarily, not these peripheral issues that don't really matter, like how many votes a meta post receives...

usukidoll

ya -_-

Jasper Loy

@usukidoll I really love that kid, he is so like me when I was that age, LOL.

usukidoll

sometimes I get downvoted, but I just shrug it off and try to gain my rep back by posting new relevant math content with LATEX

user84215

Some users may want to impose their thoughts on others.

usukidoll

gawd those downvotes on you buddy

it's a sin

So In Naughty z.o.n.e

Jasper Loy

13:10

@aminliverpool They are not harming you with a click of the mouse on a post of yours on the internet.

user84215

with a click?

SteamyRoot

It was already explained that upvoting or downvoting on Meta is not about judging the quality of a post like on MSE, but about voting whether or not you agree.

Jasper Loy

@aminliverpool If they say things which are psychologically abuse, then that is a real matter, but I don't think it even remotely falls into that category.

SteamyRoot

Apparently, most people disagree with you, and you can't accept that.

Jacksoja

Hi chat , is homeomorphism symmetric relation ?

user84215

13:11

They may want to impose their thoughts on others.

Jasper Loy

@aminliverpool Now that is a very deep sentence, and you should think more about that, and maybe you will get the answer you need...

usukidoll

ugh

user84215

They are not most people.

SteamyRoot

@Jacksoja As far as I know, yes.

user84215

They are a few people with high reputations.

usukidoll

13:13

I got that confused with homomorphism which was in abstract algebra

Jasper Loy

@aminliverpool What do you mean by imposing your thoughts on others? Ask yourself that, and maybe you will get the answer.

usukidoll

I looked at some really old chat that I posted back in 2013

Jasper Loy

@aminliverpool Yes, so they vote on posts and stuff like that which is how this site works, and so what? So what?

usukidoll

holy crap I sounded so not confident lel. Times have changed ;p

Secret

0

Q: Is isomorphism symmetric?

It is from Jech's "Introduction to Set Theory." I think that symmetry doesn't follow from it, it has not been mentioned that the function $f$ is $onto$ (that it covers all $Q$). If two ordered sets $(P, <)$ and $(Q, \prec)$ are isomorphic it doesn't mean that $(Q, \prec)$ and $(P, <)$ are isom...

elementary-set-theory

Perturbative

13:15

@Jacksoja Homeomorphisms are equivalence relations

Secret

Homeomophism is an isomorphism between topological spaces, thus what holds in isomorphism also holds in homeomorphism

user84215

They do not like new ideas which may endanger their positions.

Perturbative

So if a topological space $X$ is homeomorphic to $Y$, then $Y$ is also homeomorphic to $X$

SteamyRoot

@Secret A graph isomorphism is different from a graph homeomorphism.

Perturbative

Heya! @Daminark

SteamyRoot

13:16

In particular, two graphs are homeomorphic if they have respective subdivisions that are isomorphic

Jasper Loy

@aminliverpool Yes, and so what?

Jacksoja

Homeomorphism is when you have a graph H for example, you do subdivision on it to get G_1 and other subdivision to get G_2

G_1 and G_2 are said to be homeomorphic

But what is the relation between H and G_1 ?

user84215

We should not allow them.

Jasper Loy

LOL

Secret

Ah in that case I don't have the background to answer, steamyroot and co will take over this answering process

SteamyRoot

13:17

I don't really have a background in graph theory either :P

I only know some basic definitions

Jacksoja

@Perturbative @SteamyRoot Please look at what wrote , I really need to understand this idea for planar graph theory

Secret

I know some deep things, and some basic things, but not stuff in between (the theorems)

usukidoll

maybe we should just give him a crunchyroll account -56...oops -58 in total downvotes is just nuts

Jacksoja

Homeomorphism is when you have a graph H for example, you do subdivision on it to get G_1 and other subdivision to get G_2
G_1 and G_2 are said to be homeomorphic
But what is the relation between H and G_1 ?

Perturbative

@Jacksoja Whoops sorry

SteamyRoot

13:18

@Jacksoja Well, two subdivisions of the same graph are obviously homeomorphic.

Jasper Loy

@aminliverpool Why not you let them do what they want and you do what you want yourself. If you want to post on meta, go ahead, but you can't stop them from downvoting you. If you want to email SE team, go ahead, but you can't stop them from telling you your concern is no issue at all. End of story. I won't say anymore ever about this matter.

3

SteamyRoot

And the original graph will also be homeomorphic to any of its subdivisions

Jacksoja

There is a theorem that sais all non-planar graphs must have a subgraph that is either homeomorphic to K_5 or K_(3,3)

I still don't know how to work with that :/

user84215

-12

Q: We are the 99 % , now in the MSE [not duplicate]

I have posted the following two posts in the Meta MSE: How can we create a free university within MSE? and Are downvoting and upvoting performed fairly I saw that in less than one day, they were attacked by flood of down votes. And some users with high reputations put them on hold as "off-top...

discussion meta soft-question stackexchange advice

The Raiders of Las Vegas

yesterday, by skullpatrol

I give up.

Jasper Loy

13:22

OMG

SteamyRoot

@Jacksoja Yeah, sorry, that goes beyond my knowledge I'm afraid.

Jacksoja

@SteamyRoot Thanks for help anyway :)

SteamyRoot

I'm pretty sure that, if you make a question on MSE, someone will have the required knowledge

Jasper Loy

@TheRaidersofLasVegas LOL

usukidoll

@JasperLoy IKR

Jacksoja

13:23

I will make a topic :)

The Raiders of Las Vegas

:-D

SteamyRoot

@aminliverpool So basically, you dislike 1) the voting process on MSE; 2) how Meta works; 3) high-reputation and longtime users; 4) the entire moderation system.

And you come to MSE and want them to implement your idea of an open university on their website.

If you dislike so many aspects of MSE, why not start your own website for your idea?

9

The Raiders of Las Vegas

^

usukidoll

^

user84215

1)downvoting process 3) not all of them 4) not all of it

usukidoll

13:26

liverpool: Do you wanna build a snowman?
Everyone else: NO GAWD NO NO GEEZ NO

user84215

We can change them all together.

ShankRam

i have this c++ code for sqrt using newt-raphson method. but i am getting WA on the online judge

is there any problem with the method or the no of iterations?

ideone.com/9wZTk1

Jasper Loy

@usukidoll I prefer Jacob Sartorius to Justin Bieber. At least he is still a good boy.

usukidoll

what if liverpool is Justin Bieber?

Balarka Sen

Liverpool: you are wasting your and everyone else's time by pursuing this. the meta post has proven that majority of MSE users does NOT want your "novel idea" materialized - even if they have nothing constructive against your idea, they have shown their disapproval. The community thinks it's a bad idea; there's no point to arguing about the community on why and whats at this point

11

ShankRam

13:30

then england is my city

SteamyRoot

@ShankRam wait, what does your code do exactly?

Jasper Loy

@usukidoll That's not possible. I mean to say that I don't like Justin anymore.

SteamyRoot

Newton-Rhapson iterations of an already specified function on an already specified point?

ShankRam

@SteamyRoot it finds the sqrt

well, i took the initial value as the num/10 then did iterations with it

SteamyRoot

It seems to work on TIO

tio.run/…

Balarka Sen

13:31

The kind of people who pursue these far-fetched ideas are named as cranks by the scientific community. The same will happen here. If you continue on this idea, the same will be said about you, at the back if not in front. You will at best be an internet meme.

2

SteamyRoot

well, sometimes, that is

Balarka Sen

The rational thing to do is to give up. It was an idea, you asked if it was a good idea, community says no, and you move on.

SteamyRoot

16 gave me 4.0000 but 9 gives me -nan o.O

ShankRam

@SteamyRoot it does, but when the number goes to say, 10^18, i dont know if it will work

Jasper Loy

@BalarkaSen I am very open to ideas, to the point where people may call me crank sometimes, but the MSE University idea is really nonsense to me, I must say.

ShankRam

13:32

make that num/5 instead, that should woprk

my bad

usukidoll

yup

where's robjohn? Haven't seen him in a while

SteamyRoot

Oh, your code was made to only work for integers $\geq 10$ ?

Jasper Loy

@usukidoll It appears he doesn't come very often anymore.

ShankRam

yup. only integers

also, how many iterations in general is safe for newton-raphson when the roots are far enough

?

SteamyRoot

That's.... a difficult question :P

ShankRam

13:35

:) i knew that would be the asnwer

Jasper Loy

@usukidoll I watched all of Jacob's youtube videos for a while, but I have stopped for a while. =)

ShankRam

more like, can't say i guess

SteamyRoot

It's good to have an absolute bound on the number of iterations

but, you may also just want to check the difference between two subsequent interations

ShankRam

yes, thats a good idea

that might bring the runtime down

when dealing with large projects

thanks for the help peeps

cya :)

Anonymous

0

Q: What will be the form of the equation of a standing wave in circular form as shown below?

Following is the image of a 3D standing electron wave in circular form. Each of its loop moves up and down (while the adjacent loop is supposed to be $\pi$ radians out of phase) i.e. out of the plane and also into the plane. I think the wave equation should be something of the form $z=\sqrt{r^2-x...

physics graphing-functions 3d

Anonymous

13:44

Could someone help me with this? ^

Anonymous

@BalarkaSen Any ideas?

Balarka Sen

@Blue cute question. i don't know off the top of my head how to write that as a level set

Anonymous

Np, let me know if you get it

Anonymous

Maybe @TedShifrin can answer it

Balarka Sen

yeah that's the person to ask

or @Semiclassical

Anonymous

13:51

Also cc @Semiclassical

Anonymous

:)

Balarka Sen

actually, uh

I misunderstood the question. So this is a curve in $\Bbb R^3$?

which wobbles up and down along say the unit circle in the xy plane?

you can't write that as $z = f(x, y)$ then. That cuts out a surface in 3-space

Anonymous

Forget z=..then. Can we just write it as f(x,y,c)=0 ?

Balarka Sen

That cuts out a curve on the xy-plane. Your curve moves out of the xy-plane quite often, if I understand correctly?

Anonymous

@BalarkaSen Yes

Balarka Sen

13:57

So you cannot do that. However, you can parameterize it easily. $f(t) = (\cos(t), \sin(t), \sin(t))$ should work?

That should trace out one state at a fixed time of the vibrating circular string in $\Bbb R^3$

Kirill

question: I have two points $A(2,1), B(1,0)$ and $f(x,y) = x^2 + y^2$, so I have $f(A)=5, f(B)=1$. Now, $f(B)-f(A)$ shoul be $-4$. But if build a segment between two points $(2,1,5)$ and $(1,0,1)$ the program tells me it should be $4.24$. Why?

anakhronizein

Why what?

Kirill

What why what?

Doesn't the absolute value of the difference of two function values equals the distance between them?

Lucas Henrique

hey.

anakhronizein

You found the distance between two points A and B. Then you choose two different points, this time in 3-space, and find the distance between them. Then you ask "why".

Kirill

14:11

Don't you mention that the points are $(2,1,f(A)), (1,0,f(B))$?

Lucas Henrique

what should be what?

Kirill

sorry?

Lucas Henrique

"but if I build [..] the program tells me it should be 4.24". what is "it"?

anakhronizein

@Kirill do you think that f(B) - f(A) should be the same as the distance between those two points?

Kirill

@LucasHenrique the difference of $f(A), f(B)$

Lucas Henrique

14:14

Oh. So you generalized $f(x,y)$ to $\Bbb R^n$

Kirill

@anakhronizein at least I thought so. The function values are seen as points in the space, so I thought that the difference of the function values should be the distance between them. Am I wrong?

Lucas Henrique

So think of $f(\mathbf{x}) = |mathbf{x}|^2$, where x is a vector

anakhronizein

You are doing the distance in the graph.

Kirill

@LucasHenrique more generally I try to interprete the MVT visually in GeoGebra, and need the difference of the function values on the left side of the equation.

@LucasHenrique and I try to understand what the difference visually should be

anakhronizein

Distance in the graph is not the distance in the image.

f is a function from R^2 to R.

So for the first you are measuring the distance in R, but in the second you are measuring them in R^3.

Lucas Henrique

14:17

Try to use that definition and you should see the difference algebraic difference of what you think and what you have in terms of functions

Kirill

@LucasHenrique what is an absolute value of a vector? The sum of components? The maximum component?

Lucas Henrique

Its distance to the origin.

Kirill

@LucasHenrique 2-norm?

Lucas Henrique

Yeah

Kirill

@anakhronizein what do you mean with "first" and "second"?

anakhronizein

14:20

First --> f(B)-f(A).
Second --> distance in graph

Lucas Henrique

I'm using my cellphone so I won't use beautiful LaTeX

Kirill

@LucasHenrique but you wrote $f(x)=\langle x,x \rangle$, right? (lets try angles, hope this renders to you correctly)

Lucas Henrique

$f(x) = |x|^2$. The line segment of two points (that can be though as vectors) is $x-y$. Therefore the square of its length is $f(x-y) \ne f(x) - f(y)$

@Kirill my cellphone doesn't render LaTeX, so I'm just reading it. :p

Kirill

@LucasHenrique, oh , then \mathbb{C}^{n \times n} should be a pain to read...:)

Lucas Henrique

Not at all hahahah

Looks ugly, tho

Kirill

14:26

not this one for sure. But there are some things like big matrices with greek letters are subindices that I cannot read normally.

the one should be a compiler himself with a sheet of a paper then

Kirill

15:16

got its, @LucasHenrique. That should be the difference in the height, sure.

Balarka Sen

Hi @Daminark

SteamyRoot

15:34

No wonder my laptop randomly shut down... pushing 350 fps on a badly optimised game >.<

Kirill

15:52

the gradient for $f=x^2+y^2$ in the picture above is $(2x,2y)$. How to draw it in some point $(x,y)$? Is that a vector $(2x,2y)$ starting at the origin?

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$Mathematics$ Mathematics