@ccorn no, i am dealing with a single cell

@AwalGarg the SQL interface typically does not know which queries result in single strings

@ccorn MySQL, it seems to do so in another case which I dealt with a while earlier

@AwalGarg In any case, I'd look at what object type you actually got

I think I failed my psychology exam

@user127001 what makes you think that?

@user127001 explain?

@ccorn Catchable fatal error: Object of class mysqli_result could not be converted to string in C:\wamp\www\confirmaccount.php on line 16

I didn't study + I just checked my answers with my notes

@AwalGarg Now find out how mysqli_result is defined

I got 100s on the previous 2 exams so I thought it would be easy but I guess I needed to study lol

@user127001 Hmm, once exam is over, don't think about it, until you get the result

@ccorn umm, didn't quite get that. I am new at php

@AwalGarg Golden advice.

Hi @DanielFischer

@Sawarnik take the advice and give me gold, lol

Also I have a calculus exam tomorrow I didn't study for because I spent all my time studying for algebra

Hi @skullpatrol.

@user127001 vector calculus?

@sku It's just called 'calculus 4'

same thing

@user127001 I bet, if I were in your place saying that to my teacher, my completely idiot teacher would ask me, As if you have studied complete algebra and now you are a master at it!!!. Teachers are silly here in India...

@AwalGarg Def of mysqli_result. No wonder it's not convertible to string.

I did bad on the last calculus exam because I didn't know what linear approximation was so I missed a problem. But I got the all the other tangent plane problema correct lol

@ccorn how do I assign its string part to a php variable?

I haven't ever seen a user with completely blank and transparent profile picture...

@AwalGarg I'd have to make blind guesses. I suppose you are in a better position to try it out. But don't try nonsensical stuff. It might work, and then you would be puzzled even more.

I don't know what the accepted answer means, can you help me @ccorn

@AwalGarg As declared, I'm not into PHP. But anyway, it means you get a result in a general format (you could get multiple rows with several columns each). Each row may be fetched as an associative array. That is indexed with the column name.

@ccorn why that loop?

@AwalGarg Because the result format allows for several rows. Even if it's just one, you'll have to fetch_assoc it.

@ccorn so, if I am dealing with a single cell, can I skip the loop

@AwalGarg :P

@AwalGarg If you know that you get precisely one row (neither 0 nor $\ge 2$), then yes. But that's a typical point of failure: Making assumtions about what will happen

@ccorn yes, I am sure I will get one, I am querying with a primary key in the where clause.

@ccorn It now says - Notice: Array to string conversion in C:\wamp\www\confirmaccount.php on line 17

@ccorn and prints the word Array when echoing it. it should echo an email address actually

@ccorn thank you so much, it is working now. You are great. Hail @ccorn

@AwalGarg What's your query? If you know the query, try it in a mysql5 session. The result will have a column name. Try $row = $result->fetch_assoc(); $mystring = $row['columnname'];

@ccorn thats what I did. works awesome

@AwalGarg Wow. Fortunately, that's been mostly SQL interfacing, not PHP

@ccorn yup

I firmly believe I am correct on this answer and the ensuing comments, but due to the way that $\int\frac{\mathrm{d}x}{x}$ is taught, I also believe I won't win.

I trust you @rob

@user127001 don't just trust me. Decide for yourself.

@robjohn Ugh. Did is focused on the reals. I'd go with robjohn, thinking complex.

@ccorn even on the reals, saying $\int\frac{\mathrm{d}x}{x}=\log|x|+C$ causes problems, but extending to $\mathbb{C}$ is difficult if they believe that it is $\log|x|+C$

I'm having a bit of trouble finding the number of Sylow p-subgroups if one is only given the order of the group. Consider a group G of order 595 = 17*5*3

@robjohn indeed

Ooops, 595 = 5*7*17.

How do I find, say, the number of Sylow 7-subgroups? As far as I can see, it can be both 1 and 85.

@AndrewThompson Wow, searching with 595 alone gives somewhat relevant or at least related hits, for example this one

Haha, wow, I must have missed that. I'm sorry.

@robjohn it is especially hard to "unlearn" what you were first taught, no?

@skullpatrol that depends on how you learn, but in general, yes.

yes, in general

and then there is the "force of habit"

@robjohn How would you teach someone "how to learn"?

or can it be taught

@skullpatrol meta learning?

@robjohn Like this?

@skullpatrol sounds pretty close.

@skullpatrol only by giving examples, I suppose.

@ccorn Indeed, those must be carefully chosen.

imo

@skullpatrol It's the number of examples that trains. Abstraction need not be taught, it's a natural process. The examples give the details needed for imagination.

Adding details is the difficult part. Abstraction is removing details, that's easy.

(Which is why I am so impressed by André Nicolas's ability to give a combinatorial problem in order to explain a summation identity.)

Is he French?

@skullpatrol I don't know. I'd guess so if I had to (but I don't have to)

Parktime. I have a dog who won't let me forget :-) BBL

ei skull, rob and ccorn, how did y = c became a solution? puu.sh/8pBo4.png

@IvanMatala The "initial equation" seems to have been something else, not the ODE shown

I see. full excerpt puu.sh/8pBJ6.png

@IvanMatala Before dividing the 2nd equation by $v$, you have to consider $v=0$.

I see tnx

@ccorn Actually, it seems italicising spaces would save space - see this here

@AwalGarg OMG

@ccorn i wonder if it works with other fonts as well. gonna try in a while

@AwalGarg The italic font has tighter kerning. Spaces may still have same width.

how do they have tighter kernings?

it does not happen for ubuntu monospace

@AwalGarg The bounding boxes of characters are pushed more closely together in the italic font than in the upright font

I tell you, there is something with fonts...

@ccorn I don't think so, let me see more clearly

i see the opposite happening when I zoom in

upright font is packed closely than italics

Fonts are the new night sky. Everyone looks at them, and no one can explain everything he sees.

so what about ubuntu monospace?

@AwalGarg Monospace just slants. No change in overall width.

@ccorn hmm, i thought this applies to every font. Okk, thats where the confusion arised from

(In my browser, currently Safari. On Firefox, I have disabled all interactive stuff)

@ccorn I had a presentation to my math advisor on the algebraic geometry of the quintics.

Involved a lot of modular function analysis.

@BalarkaSen Hi Balarka. Nice to see you again in here.

@BalarkaSen Hey, heard a lot about you from some kids

@AwalGarg Those prats.

@BalarkaSen sawarnik and cawk

@ccorn Thanks. Today I gave a presentation on the Galois covering $X(5) \to X(1)$

@AwalGarg I'm here.

That involved a bit analysis on hauptmoduls on $X(N)$.

@Sawarnik you give me my gold...

@AwalGarg I said golden not gold :P

@BalarkaSen Does prats mean rats?

@BalarkaSen Congratulations.

@Sawarnik is a golden necklace not made of gold?

@AwalGarg But a golden anything is not made of gold, for eg advice :P

@Sawarnik golden means, it costs same as gold. now atleast pay the cost...

@ccorn LOL, whats the congratulations for? It's a pain to derive the hauptmoduls on $X(N)$ (unlike $X_0(N)$)

@BalarkaSen Agreed

@AwalGarg golden means, its colour/properties is like gold :P

@ccorn I am having a bit of trouble realizing $X(5)$ as a Riemann sphere, can you help?

I have derived that there are 12 cusps, that part is done for.

But what of the fact that $X(5)$ is topologically homeomorphic to a disk in $\Bbb C P^1$?

@BalarkaSen I would have to delve into that just to follow what you have already traced out

Balarka serious today.

@ccorn OK, I can explain what I am doing. Do you have time to listen?

@AwalGarg Sorry, not rigorous enough.

@BillDubuque might be fluent in $X(n)$ (I'm guessing persons here---mentioning those who answer questions I am interested in)

And can you give me a golden mobile!

@Sawarnik now?

@Sawarnik go to the market for that (and take some money)

Either you are a poet or your memory is very good.

@BalarkaSen the goldless will then be guilded

Sheer memory.

@BalarkaSen You're contradicting yourself.

@BalarkaSen I will listen, but I cannot promise that it will help. Anyway, others will listen too, and there may well be good hints.

@ccorn I see. But you might be interested in the connection with quintic here

@Sawarnik ok, thats enough rigourous list now after the edit, give me gold now

@AwalGarg Not yet!

@Sawarnik ok, how many left?

@AwalGarg Not yet!

And I don't think you ll ever.

@BalarkaSen Yes, of course, although that's more the realm of Tito Piezas III --- I am a bit worried that he seems to have no fresh questions. I might have driven him away, would be deeply sorry for that.

@Sawarnik you kiddo, its not nice to steal gold, that too, online, in a public chat room. Let me call a mod

@AwalGarg No, your proof was wrong. Sorry, fix it.

@ccorn Yes, indeed, Tito is really the quintic guy here. OK, how about this : We collect the persons interested in these branches into a room focussed over theory of equations only. How about that?

@Sawarnik math people don't understand a physicist's point of view

@BalarkaSen choice of room does not matter much. It's not really noisy here. Most of the time, topics do not overlap. But do as you please.

Walk like men, talk like math.. math-people..

No wait, other way around.

So 101 is smaller than 100.QED.

@Sawarnik we have a contradicting proof - 101 as you said.

@ccorn Fine, let's continue discussions here. But think of peoples who can help, and we will ping them on. Let me now write up my point of view of these things.

in my case, there is no contradiction

@AwalGarg There is. Your experimental errors.

@Sawarnik yes, they are experimental and they are very few, you have infinite

@sawarnik That's the induction trap, not considering what future cases may bring with them.

Goes for the same with the golden idea.

@Studentmath hey, nice username, I should change mine to TeacherPhysics

Thanks! But without the capital in physics, makes it too readable.

OK, here goes : Consider the covering map $X(1) \to X(5)$. The point here is that this is a Galois covering with Galois group $\text{PSL}_2(\Bbb F_5)$, which is derived by considering $\text{Gal}(\Bbb C(X(5))/\Bbb C(X(1)))$ which can be viewed as the deck automorphisms on $\Bbb C(X(5))$ fixing the subfield, which has galois group the image of the deck transformations over $X(1) = \text{SL}_2(\Bbb Z)$. The point now is that $X(5)$ is also a Riemann sphere and has 12 cusps.

@BalarkaSen Paul Garrett of course, but I am not acquainted with him so I hesitate to use @ here.

@ccorn @TitoPiezasIII

@AwalGarg No.

you can ping Aryabhatt ofcourse, or Newton

@AwalGarg How.

@Aryabhatt @Newton I invite you to help @BalarkaSen and @ccorn

@Sawarnik it wasn't aimed at you, kid

@AwalGarg There is one Aryabhatt here, but not at chat.

@AwalGarg There is no Newton on chat idiot.

@Sawarnik If you are talking about me, I am on chat... (lol)

@AwalGarg Afaik, you are Awal Garg.

@Sawarnik equivalently (or may be a little bit more) genius as Aryabhatt and Newton combined (lol)

btw, Awal Garg is not my real name

its an anagram of my real name

geeky

Lawl Ragr?

@Sawarnik no... anyone won't be able to decode it ever...

@AwalGarg Finite cases.

lets see, you would need Jon Skeet and his computer for that... may be much more than that

@ccorn Now the connection with quintics come from the fact that $A_5$ is a permutation on 5 elts, where $\text{PSL}(2, 5)$ is a permutation over $\Bbb P^1(\Bbb F_5)$, i.e., 6 elements. This gives us a interpretation of the resolvent sextic of the quintic equation , as described in Kiepert-Perron algorithm (ref. R. B. King) which is solvable through elliptic functions. (why?)

@AwalGarg Enough of useless discussions. Become serious like His Royal Highness Sir Balarka Sen.

@Sawarnik not until 29th thats, day after tomorrow

@AwalGarg No.

@Sawarnik yeah right, lol should not be there, after all, its a fact (lol)

@AwalGarg No.

@Sawarnik ok, you mean lol should not be in that one as well?

@AwalGarg No.

@Sawarnik you should stop spamming with the word 'No.'

@AwalGarg Yes.

@BalarkaSen plus one

@BalarkaSen Does prat mean rat?

@Sawarnik plus one for that as well

@BalarkaSen Don't speak like Pedro. Study like Pedro. :-)

@ccorn True indeed.

Let's try to keep this on-topic. When we draw moderators in from other chatrooms, that's a bad sign.

But I don't like finite group theory.

And whoever starred that post calling Swarnik a name... I'm requesting that you unstar that.

Dunno the history here, but flags started flying so yeah.

@Sawarnik You're right! $\small101$ is smaller than $\large100$

@anorton took care of it.

@Seth Thanks. Mod powers must be nice to have... ;)

@Seth I think it's better to delete that as well.

@anorton "With great power comes great responsibility" ;-)

@BalarkaSen probably.

@Seth True... one of these days, I hope to be a mod. But that will probably be in several years...

:)

@ccorn Have you read Mumford's Tata lectures on theta?

Well, I'm out. If Will Hunting drops by tell him hi for me. (I think his name was Will last)

@BalarkaSen No

@Seth He is Jasper now, again!

Wow, I asked a question I already asked and don't remember ever asking it

@user127001, thats funny

@robjohn can you help me in solving a Topology question, which I was discussing with Mike yesterday, but I found a mistake in my solution

@anorton drawing moderators from other rooms

@Mike, my solution yesterday was wrong.

@robjohn haha nice.

@Ram I don't know if I can help. What is the question?

I had another question, but narrowed down to this

f: P2#...#P2 (2n sums) to T2#......#T2(n sums). If I look at f_*(H^1) how does it look like? I mean can we say some thing about this with out any information on f?Lets take coefficients in Z2.

I thought, this should be trivial on H^2, came up with a proof, but not quite working

and hence on H^1 (by looking at cup product which is wrong)

@Ram I don't think I can help with that one, sorry.

Ok, no problem.

@robjohn edge detection in Photoshop, I suppose?

@ccorn Plastic wrap in Photoshop (or equivalent) is my guess.

@ccorn yeah... glowing edges (after a gaussian blur to remove the pixelation)

Then an inversion to get the black on white

@robjohn Ah, glowing edges... yes, the look seemed somewhat familiar to me :-)

@ccorn the exif data was stripped by imgur, otherwise, you could find out from that :-)

@robjohn Yup!

Is that image Newton?

@Sawarnik yep. I think it's the one used by Seth

@robjohn Is the limit at 2 is 3?

@Sawarnik from the right, it appears so.

@robjohn No the limit, no right-left.

@Sawarnik but it depends on the domain of the function

@robjohn Its defined at all real greater or equal to 2.

@Sawarnik the limit doesn't exist if the function is defined to the left

@Sawarnik then the limit is $3$

@robjohn You mean even if it doesn't exist on the other side of 2?

@Sawarnik only if it doesn't exist on the other side of $2$. If it did and did not meet up there, then the limit does not exist.

@robjohn Oh, I used to think that the limit doesn't exist it isn't defined on the other side.

Stewart taught me that.

@Sawarnik if it is not defined on the other side, it's domain is $[2,\infty)$ and on that domain, the limit is $3$

@robjohn Stewart gives me a definition and an example to teach the opposite. Feeling cheated. math.stackexchange.com/questions/770069/…

@Sawarnik that says "$f(x)$ is defined on some open interval containing $a$, except at possibly $a$." your function does not meet that criterion

@robjohn And so the limit doesn't exist...

@Sawarnik no, your example does not fall under that case

@robjohn Y?

@Sawarnik because your function is not defined on some open interval containing $2$

@robjohn Yes, so it fails the first condition and the limit is not defined?

@Sawarnik that is not a condition for the limit, that is a condition for the definition. It is not the most general definition for a limit, but it works in many cases.

@Sawarnik that statement does not say anything about the case you've drawn above.

@Sawarnik The limit is defined. Every sequence of $x$ that converges to 2 lets $f(x)$ converge to the unique value $3$. That's the limit.

It could be different if $f$ were defined for $x<2$ too.

@ccorn yes, but he is working from the limited definition here which does not cover the case drawn above

that definition does not cover the case where the limit point is on the boundary of the domain of the function

@robjohn Oh, I see.

@robjohn Yes. So the given definition does not completely cover our understanding of limit

HI! Sorry, I can't find a suitable url on math.SX.com with the "definition" of MWE. That would be very useful to link in comment to new users' posts. Thank you!

@MattAllegro what is MWE?

@MattAllegro MWE is minimum working example Useful for questions about code.

@ccorn ah

@MattAllegro Often used at Stackoverflow and on TeX.SE.

good morning @robjohn :P

@TedShifrin hey there... don't bite your tongue :-)

I can't help it you're lazy on the west coast :P

@TedShifrin lazy? why say you that?

starting the day 3 hours later than we do, of course

@TedShifrin no, the sun is lazy... getting up three hours later here. It's all his fault.

now that you mention that, I was told last night that all of China is on one time zone, so at the eastern end the sun rises around 3:30 am ...

@TedShifrin hmmm... let me check that.

@robjohn No, its the Earth's fault.

@TedShifrin Ack!

@Sawarnik the Earth has many faults. A lot of them are in California

My friend (who was recently in China) would be upset to know you didn't trust him :D

@robjohn But it's good at its core.

@TedShifrin you didn't mention your source, so he shouldn't care.

I'm sure the NSA, with all their spies, already know.

@ccorn it has a heavy heart.

Hi @rob @Ted

hi @user127001

@user127001 hello again.

@ccorn: Hi! so we don't use tha name MWE in here?? ;) Is there a link with instructions for good questions etc.??

@MattAllegro I've never seen MEW used here on Math.SE. Ask @robjohn :-) That said, I'd wish new users would take more time to format their questions properly.

@ccorn: They're too busy trying to get their homework done to bother. :D

@MattAllegro TeX.SE mostly requires MWEs. Here is a meta post about that.

heya Mr @Pedro

@ccorn: meta.math.stackexchange.com/questions/9959/… this is also good, but thank you! I won't call it anymore a "MWE" on math.SX ;) thanx again , bye

@MattAllegro you can look in the help center

Why is the main site not opening?

Nor the meta it seems. Is anyone else having the same problem?

@MattAllegro especially here

@robjohn I thought california was a beautiful place?

@Sawarnik it is working for me

Still not for me :(

@Sawarnik Every plate has some cracks. Some are just more well hidden.

@robjohn What do you mean?

Opens finally!

@Sawarnik You may take that literally.

@ccorn Ok, I see. But is that a problem?

@Sawarnik not for me :-)

don't do cracks

@Sawarnik 'twere a metaphor... with double entendré

@robjohn, I think I rectified issue in my solution.

But I hope some one will verify it.

@AlexanderGruber I have a problem for you.

Finite group theory.

what's that

$G$ be a finite group of order not divisible by $3$ such that $\forall x, y \in G$ we have $(xy)^3 = x^3y^3$. Prove that it's abelian.

It's a beautiful problem, in my opinion.

Wonder if you ever did it, @AlexanderGruber

@BalarkaSen i don't think so

Then try it. I will ping @PedroTamaroff too. Ping me back if you want a hint.

@BalarkaSen I don't really have time, man, sorry. It's finals week, I have too much to do.

maybe next week

@AlexanderGruber OK.

I have to show this critical point is a saddle but the determinant is 0. What other method can I use to show it's a saddle

Greetings

@Ram I'm glad. I had no idea what you were saying :-)

Good day :)

I wonder if Cleo is aware that there is no need for Fourier series to finish this one math.stackexchange.com/questions/418134/…

OK, this one will be my POTD tomorrow.

Is anybody well schooled in functional analysis?

@JohnDoe Better ask the question directly. I have never heard anyone here advertising his/her capabilities.

Good evening by the way, or whatever time of day may happen to be where you are.

:-)

Hi ccorn, it is evening. My question has to do with a post I put up and am interested in resolving soon. The post is 'problem of convergence of characteristic functions'.

@Alexander?

@PedroTamaroff yeah

@AlexanderGruber

What?

I was snoozing.

i didn't ping you, balarka did

he has some word problem from finite group theory he wants us to do

Oh. Not now. =P

Cheers =)

Kill those finals.

@PedroTamaroff yeah same here

gotta finish my commutative business and i'll be good to go

i'm learning about symmetric forms and wedge products and all that

:15196711 Judging from related questions by you, I'd recommend just to wait a little while. The users subscribed to those topics seem to take between 90 mins and 1 day to notice and answer.

Off to an art fair BBL

That's diff geo @Alex?

Cool question

@Pedro: That stuff is algebra that's used in differential geometry, among other places :P

Hi @Fernando

Hi @Ted

I want to be able to downvote comments. Now.

I'm sure plenty of people have wanted to downvote some of mine, @MattN.

@TedShifrin I'm not talking about yours.

Well, perhaps not in this particular instance you're not :)

I've been wanting to downvote comments for more than 3 years.

But, I concur. There are a number I would like to have downvoted myself.

I'm amazed, though, by some of the wrong answers where I've downvoted and explained why they were wrong in comments ... and nothing happens.

There are just too many wrong comments out there. And the exact reason why these commenters chose to comment rather than post is because they know exactly that they don't really know what they're talking about.

@TedShifrin Ugh. That sucks.

@user127001: To answer your question above, you have to look at the function's values near the point in question. Or find a third-order Taylor polynomial.

But speaking of comments -- did you see my comment to you?

Well, I myself was idiotic yesterday and posted both a comment and an answer that were wrong. But I deleted them as soon as someone pointed out to me that I was an idiot. :)

I do too when people point out mistakes to me.

Yes, @MattN, if I remember correctly, you pointed out a typo. But we can't change comments after a few minutes, so I couldn't fix it. :( I didn't think it was worth deleting and retyping, since it was fairly evident what I meant ... and you corrected the typo :D

@TedShifrin Sure, I just wasn't 100% that it was actually a typo.

I offered 500 points bounty for math.stackexchange.com/questions/737311/…. Maybe you're interested ...

Yeah, sure. It's a matter of habits ... When I teach multivariable, things are in $\Bbb R^n$, so I always am careful to use $k$ for my indices on sequences and series. But in single variable settings, I go back to old customs and use $n$ ... well, I meant to :P

But I'm glad, now I know.

But aren't you amazed I remembered you, @MattN? :D

@TedShifrin see what I wrote above ;)

@TedShifrin What? I only posted that comment a couple of hours ago. Is your memory that bad? : )

LOL, @MattN, it used to be spectacular, but I'm accepting the realities of getting older. :(

@Chris'ssis, ordinarily, your taste in math and mine are quite opposite. This is yet another occurrence of that phenomenon.