What is the shortest way to connect all the cities? For example, Paris, Dieppe, Brussels and Zurich could all be connected with just 6. Similar to travelling salesman, but not identical. Sorry if there's a name for this and it's easily solvable.
My best so far is 108.
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>>8167079
>just 6
if you use 6 lines to connect 4 nodes, you have no more possible combinations of nodes left to connect.
how is this a problem? its fucking trivial, there is no minimization here and a 10 year old could derive the generic formula for the correct answer
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>>8167102
I was just referring to those four cities as an example. See picture for acceptable solution.
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>>8167112
This would be quicker if it was classic travelling salesman, my point is that the problem isn't.
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Hi /sci/. I recently started learning about fundamental groups in algebraic topology. It worked fine for me until i needed some actual knowledge of group theory (normal subgroups, free groups, generators...) .
What do you recommend as a good reading for group theory?
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>>8166961
armstrong is a decent introduction
for all the details you can go with robinson
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>>8166961
You could honestly just pick up any Algebra book, and what you're looking for will all be in the first chapter or so. Hatcher also has a sufficient exposition on free groups in the section on the Van Kampen theorem.
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>>8167121
thanks, I was looking for it because of Van Kampen theorem
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Why are some things alive and others not?
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define alive
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>>8166938
If you have a chair and a person sitting on the chair, why is the person "animated", but the chair isn't?
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>>8166951
define animated
Anonymous
Why do the Liberal Arts suck so back compared to STEM 2016-06-27 11:15:46 Post No.8166911
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Why do the Liberal Arts suck so back compared to STEM 2016-06-27 11:15:46 Post No.8166911
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Why do the Liberal Arts suck so back compared to STEM
Anonymous
2016-06-27 11:15:46
Post No. 8166911
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There seems to be a major discrepancy in usefulness between pretty much all liberal arts majors and essentially any STEM degree.
Every single graphic design major or post-art school grad I know is either :
1. Going to an expensive university and drawing things for 10 minutes a week, no other homework or studying required
2. Working a 'freelance' job wherein they have absolutely no clients or major salary to be heard of regardless of their talent or 'exposure'
3. Working somewhere completely unrelated to artistry and makes minimum wage, vehemently tells everyone to stay away from Unis because they are "huge ripoffs" for every single major in existence
In contrast to art, STEM grads literally are working at an actual job pertaining to their degree after graduation, and they often make a great salary doing legitimately useful and rewarding things for society/ their company.
Why has it gotten this way, /sci/? It seems like everyone, specifically Millienals have forsaken mathematics, scientific reasoning, and motivation to learn about the workings of the universe in general.
It makes no sense to me that instead of wanting to learn about something like maths or physics people would rather be painting something, and are actually encouraged to do so and shamed for studying STEM.
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because STEM is hard and or boring and arts is interesting and fun. besides, i'd rather chase my "passion" for $10,000 a year and not think about the future or getting a job relevant to my major.
not to mention being a nerd is totally uncool. like gross!
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Physics hasn't captivated the general public since we built the bomb. Blame the following era of anti-intellectualism on McCarthyism.
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lib art major here.
As much as this is true, your position is directly proportional with your skills and how much you're willing to push it. Contrary to STEM degrees where knowledge is the main necessity, liberal arts usually look for originality and imagination alongside to the efficiency of how someone uses tools, programs and so on. You can either waste time designing 2d logos for chickenpiss money, or you can design apps and games for mobile and PC and earn enough money to build a company. Especially the mobile industry is on rampage as it established to reach millions of users online so easily.
Also these jobs have a whole other bonus for being very casual and chilling. Even corporate model workplaces have a significant space they give artists where they can be comfortable.
t. game designer
Are viruses evil?
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very science
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>>8166897
>Is earth true?
>Are dolphins casual?
>Is time priority?
There is no need to clarify anything as good or evil. Why can't you just apricciate it without judging it with Your human standards?
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No.
Humans kill/use plants and other animals to eat and survive.
Viruses kill/use plants and animals (including humans) to survive and multiply.
Their intention is to survive, as is the intention of humans. They're just as evil as we are.
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Does anyone know how I can animate a motional process (in this case gondola lift, modelled as double pendulum) with Matlab using the solution matrix of the ode solver and overlaying image files.
So far I have an animation using two line segments. This was relatively easy to do but now I'd like to replace those line segments with graphics of the system.
I made a vector graphic image of the system with inkscape but I think it should be easiest to convert the two bodies involved in the movement (mounting bar and cabin) into separate pngs and using my solution vector to position those images. The thing is, I have no idea how to do that.
Any ideas? (further pictures incoming)
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here's a sketch of the system. That's what I draw in inkscape.
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>>8166862
didnt read your whole post, but when I want to animate something, I use imagesc( ) together with pause ( ).
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>>8166871
that looks promising. Thanks mate!
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Why aren't we taking memory out of the brain after ppl die and putting it into mass cryo chambers.
Deathcucks can fuck right off with their ethics, I wanna be resurrected.
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>>8166854
>liberal arts major
intothetrashitgoes.jpg
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>>8166854
>Why aren't we taking memory out of the brain
We don't know how.
>I wanna be resurrected.
Without freezing your entire brain and reviving it in the future (which would destroy it with current techniques), it wouldn't be you.
Most importantly,
>putting it into mass cryo chambers.
Ain't nobody got resources to store a century worth of people, you do realize two people die every second right?
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>>8166854
> taking memory out of the brain
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Had pic related in my lecture today and I did not get it at all.
So basically this is a circle with radius=1 on the complex plane or what?
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>>8166798
>So basically this is a circle with radius=1 on the complex plane or what?
Basically yes. e^{it} forms a spiral of constant radius 1 through the t axis. Which is why the equation pictured is a really shallow thing to be spread as some mathematical miracle - the whole picture is more beautiful to me.
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>>8166808
Okay, that understanding helps.
Thank you.
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>>8166808
you clearly don't understand it then.
Look at what if fucking says mate.
if you take a function solution of {y' = y, y(0)=1}, take its value at 1, raise it to a complex power involving pi, you get -1, which is a simple number.
It just how simplicity can stem from apparently very complicated functions and numbers: e is transcendental, pi is transcendental.
This is rare enough to be mentionned.
we don't even fucking know if pi^e is transcendental.
Are they still being used in textbooks today, or is that just a myth?
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It's real.
https://www.youtube.com/watch?v=8YmLWnQGZhQ&bpctr=1467014386
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>>8166642
The fuck did i just see
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Biology question -
If traits are selected by being passed down from successful breeding individuals
And attractive people get more tail
Why are people still ugly to this day?
Will we ever become more generally attractive?
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>>8166588
maybe attractive people were/are also dumber or less fertile.
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>>8166588
Well, we are generally speaking better looking on average than even 100 years ago. But genetic traits only have percentage chance of being passed. Also, ugly people tend to be happier, more emotionally stable couples longterm (more likely to generate several offspring)
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>>8166592
Also what you think of today as ugly was considered very attractive less than 200 years ago (especially excessive fat)
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Help. I am a 23 year old male and for almost as long as I can remember I have suffered from "lucid" dreams. I have no experience in the science surrounding dreams so I don't know if what I am experiencing are dreams or REALLY high detail hallucinations. As i have gotten older, the frequency, detail, and severity of these "dreams" have dramatically increased. I don't know where to turn for help. I feel like i am going completely insane. I live in a place where i can't even find affordable, quality mental healthcare for the shit in my head that i CAN explain... I don't know what to do.
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These "dreams" include scenarios and experiences I have never had, involving people I have never met and places I have never seen.
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Bump for curiosity
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>>8166508
why are they distressing you so much? most people have dreams and even lucid dreams.
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Sci,
Can you tell me about the human immune system and autoimmune diseases.
Specifically how TH1, TH2 and TH17 cells work, how they are created and regulated and what epigenetic triggers cause these different cells/systems to be produced.
Also will taking diindolylmethane fix my autoimmune issues, like massive food intolerances I've developed over the past 10 years?
Thanks
:^)
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Why does /sci/ hate biology?
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>>8166510
because biologists tell us that 2 identical looking dogs who can mate are from different spiece when 1 human and 1 ape from Africa is the same.
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>>8166510
Because when we start to take interest in biology we wind up on gif
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Was math invented or discovered?
Debate
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>>8166430
Take your pedophile cartoons back to >>>/a/
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Invented. Math is a construct used to break apart the universe into palatable pieces
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>>8166430
>look mom, I poasted it again
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What books can you recommend me on how the mind works, basically what books are about social interaction and how to trick and manipulate people?
I don't feel empathy towards other people emotions, but I would still enjoy to be the soul of th party.
I just want to know how to stop being blunt and stop hurting people feelings by mistake.
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>>8166406
That's called sociopathy. Stop asking stupid question on 4chan and see a doctor.
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>>8166577
*tips fedora*
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>Alien structures not yet discovered on Pluto
Are we going to have to comb the Oort cloud for intelligent life in the solar system?
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>>8166377
We should probably start looking for intelligent life on Earth first.
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>>8166377
>being this retarded
If there is life ANYWHERE else in our solar system, it's probably in the subsurface oceans of moons like Ganymede, Europa, and Enceladus. And it wouldn't be intelligent life.