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Comments:
<0> 3:40am, i slept for a few hours but i gotta get back to sleep so i can be up at 9am
<1> o ok
<1> its almost 1pm here
<0> i think what i'm talking about is a 'multiset' so trying to figure out how to calculate that
<0> er duh wikipedia has the answer
<0> (n + m -1)! / (m! * (n-1)!)
<2> % (n + m -1)! / (m! * (n-1)!)
<3> How many of you do math because it's fun?
<4> :)
<5> why else would you do it?
<3> I'm not sure, vanity perhaps. Noone will admit that though.
<5> surely not for the wagonloads of hard cash or the dozens of scantily clad female attendents
<6> now you tell me!
<7> well when I wave the mathematics brochure for my local uni around I get the same response as when I make bad puns... so worth it...
<8> Uh, I was hoping for some money later..
<4> I like people's faces when I tell them that I love math.
<6> sorje: that's ok. send the groupies this way :)
<5> sorje - there's no santa claus either I'm afraid
<8> lies! Lies!
<9> % Solve[u/cos(u)-v==0]
<9> % Solve[u/cos(u)-v==0,u]
<9> can someone please tell me how to ask mbot to solve my equation? :-)
<9> %Solve[u/cos(u)=v,u]
<10> % Solve[u/Cos[u]==v, u]
<10> but i don't think it has a solution
<9> Failure02: it looks quite simple
<11> this http://www.newyorker.com/fact/content/articles/060828fa_fact2 is an interesting account of the recent fields medal stuff
<12> yes
<12> like the part where Yau is a power-crazy megalomaniac
<12> (i do like that it was just pasted from the print version)
<1> is the field medal an international prize?
<1> like anyone anywhere in the worl can win it?
<13> Yes
<1> or US only?
<1> agh k
<13> It's -THE- international price of mathematics...
<1> so what is it awarded for?
<13> US only? Iggit! *whacks shortcircuit over the head*
<13> shortcircuit: Highly impressive mathematics done before the age of 40.
<1> o ok
<12> usually it has to be considered "groundbreaking"
<12> well, nasar's predilection for crazy mathematicians aside,
<1> i reckon it has 2 be published in a specific journal?
<12> at least the article claims nobody else has ever refused the medal before
<12> err.. drop that "else"
<12> redundancy is a painful thing
<1> coz i dont think the'll check every journal all over the world
<12> no, not in a particular journal
<12> obviously their work has to be known by the community
<1> o ok
<12> which happens when you solve a famous unsolved problem, like perelman did
<12> not that the other 3 winners didn't solve hard problems
<1> ill read tha article a little later on
<12> but perelman's problem had more media appeal thanks to those crazy bostonians (or wherever Clay is)
<1> is it 1 of the millenium prize problems?
<12> yes
<1> so someone solved 1 of them
<1> how many of them have been solved?
<12> as far as i know, just this one
<1> k
<12> although about 5 years ago there was a purported resolution of whether P=NP
<12> i'm not sure what ever happened to it
<1> sadly math isnt that a hot topic in my country...
<1> so we never here about things like that
<12> there's a country which cares less about math than the US?
<12> that's unfathomable
<1> South Africa...
<12> fathoming accomplished
<1> weve got brilliant ppl, but they all go off 2 study engineering or actuarial sciences...
<1> coz math has less than 0 appeal 2 most ppl as a carreer...
<12> that is a cruel twist of fate
<12> people preferring actuarial sciences to math
<1> we r only 2 ppl majoring in math at my university
<12> the article's a good read, because you don't need to know much about the conjecture to follow it
<12> i should say theorem now
<1> :) true
<1> but isnt it supposed 2 b under review 4 2 years...
<1> or has that p***ed allready?
<12> for the clay prize, yes
<12> there'll be a 2 year wait from basically now
<1> o ok
<12> for the proof to be accepted, no
<12> the clay institute doesn't want to dish out a million bucks only to find out that there was a mistake in the argument, so their waiting period seems like a good idea
<12> especially, it seems, since it starts following confirmation of the proof
<12> (which has taken about 3 years)
<1> thats a long time :/
<11> i imagine the clay peope are in no hurry, since he'll probably refuse it anyway
<11> also i tihnk he would need to publish his proof, which i guess is not a priority for him
<14> actuarial science? :P thats me
<15> hi, sorry for this silly question... shouldn't 0.5 be 1 when rounded? or 0?
<1> 1
<5> It's Mahmoud.
<15> the problelm is related to programming.. 0.5 goes 0 and 1.5 goes to 2.. using sprintf function in perl
<16> Mahmoud: is the pattern regular?
<16> if not it probably has to do with rounding errors due to the internal representation
<15> this is what i'm using exactly sprintf("%.0f",3/2)
<16> do it from 1/2 to 31/2 -- what's the pattern of up/down?
<15> 3/2 means 1.5.. rounded to 2.. fine.. but 1/2 which is 0.5 goes to 1.. i'm not a programmer so there is something that i don't know
<15> hmm okay
<16> floats are really weird -- if you want predictable behaviour you might have to fix it by hand
<15> 4 is 2 .. expected :D 5 is also 2 :/
<11> i suggest you ask questions about sprintf in #c (or ##c or whatever it is), in mathematics you can round fractions up or down
<15> i think i should use ceil/floor instead
<15> thanks guys :)
<11> (i mean that in a "you'll get more useful answers in a channel dedicated to a language than in here, rather than in a "dont talk about programming in here" way)
<15> I know.. acutally I'm asking in a programming channel, but just wanted to double check the math side too.. that's all
<17> sprintf on many systems implements the round-to-even method, which is recommended by the IEEE FP standard.
<17> saccade_: Floating point numbers have no errors when representing numbers of the form x/2.
<18> any know how to show sum(tan(k*Pi/(2b+1))^2,k=1..2b))=(2b+1)2b for all b>1 in N
<17> The rounding method is a feature, not a bug.
<18> a featured bug ?:-P
<17> No, a feature.
<17> 0.5 rounds to 0. 1.5 rounds to 2.
<11> yet another reason not to use C
<18> haha
<17> Now you're just displaying your own ignorance of numerical methods. Statisticians usually adopt the same rounding rules for the same reason.
<17> viz., it tends to reduce bias in the rounded results.
<18> for what reason ?
<18> yrlnry : does it ?
<17> If you always round x+1/2 up to x+1, it tends, on average, to increase the values. If you sometimes round x+1/2 to x+1 and sometimes to x+0, it tends to leave the values unchanged, on average.
<17> Yes.
<18> well if 5 is the last digit you have computed
<17> See for example: http://groups.google.com/group/comp.lang.perl.misc/msg/36af7d05ded1def2
<5> http://wikipedia.org/wiki/Rounding#Round-to-even_method
<17> http://en.wikipedia.org/wiki/Rounding#Round-to-even_method
<19> yrlnry : which rounding rules?
<19> yrlnry : if the error then is gaussian distributed you are right
<19> but if he isn't?
<17> I don't know what you mean by "the error then is gaussian distributed".
<18> yrlnry : i don't really see why it is necessarily better
<17> kmh: So?
<18> yrlnry : it just has _other_ benefits and it depends which matters to you
<17> Sure. For example, if you are in an advertising campaign, and you would like to exaggerate the effectiveness of your product, then rounding *all* fractions up to the next higher integer is desirable.
<18> yrlnry : so prefering the standard calculator method is not numerical ignorance (but intentionally chosen for a reason)
<18> yrlnry : i'm talking math not economic
<17> No. I did not say that preferring the standard calculator method was the result of numerical ignorance.
<17> I said that llll's stupid remark was the result of ignorance of numerical methods.
<18> yrlnry : if 5 is your last digit then you can ***ume the exact number lies in the upper half, which gives you a good reason to round up
<19> yrlnry gaussian = normal distributed
<17> Well, you can ***ume anything you want, but that doesn't make it true.
<19> do you now know what i mean?
<18> yrlnry : it does
<17> Manyfold: I know what Gaussian distribution is. I still can't understand your sentence, which is not grammatically correct.
<17> kmh: Oh, does it now?
<17> I ***ume that you are a purple water buffalo.
<19> yrlnry well english isn't my first language. so tell me which part you don't understand
<18> yrlnry : the case that all digits of a continued computation produces 0 is much more unlikely
<17> kmh: If the measured value is .065, to the limits of measurement, then the true value could just as easily have been .06497 as 0.6503.
<18> yrlnry : how about you talk about the mathematical argument rather than resorting to insults
<20> a bit too much subjectivity for a channel of such a sophisticated subject IMO
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