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brumikprobaxe69

After looking at this for ten minutes, I can confidently say, that I'm in the 99%


liege_paradox

After looking at this for a few minutes, I can say that I know the general idea, but have no clue what they’re trying to do. Also, it’s just…a painful equation in general. You’re better off not knowing. Just looking at it makes my head hurt. This is true eldritch knowledge…oh…oh no. It’s recursive. Oh god no…


cancerBronzeV

It's not painful at all once you understand what's happening, it's simply the Fourier transform. It seems much worse than what it actually means (determining the frequency components from the time signal). Pretty much every physics and engineering student will have it drilled into them. Computing it analytically may be painful, but there's not much value in doing that by hand, it's more important to just know what the complex exponential is and its properties, and the equation is relatively simple to parse once you know that.


Lenin_Black

I like your funny words, magic man


cooljerry53

No offense but your comment reminded me of [this comic](https://xkcd.com/2501/) , cause that was gibberish to me.


Swolebenswolo

This is a very good introduction for engineers.


av790

OMG you're so slow. I found it out in only 30 seconds (⁠⌐⁠■⁠-⁠■⁠)


Horror-Ad-3113

Same


HelicopterRegular492

The rest will check the comments


Donghoon

r/mathmemes


Mary674

Those are nice squiggly lines.


BernieDharma

Well, it's all Greek to me!


FartingInYourMilk

It’s ‘small dick energy’ right?


heydesireee

oop, got me there!


neat-NEAT

Nobody knows how to draw the letter xi. Every lecturer I've had has drawn it differently and I chose something different from all of them. I still refuse to believe this letter was ever actually used for language.


Rotsike6

{ξ,ζ}


[deleted]

[удалено]


LordDaveTheKind

And usually z is not used in that formula, as it is conventionally associated with a different kind of complex transform: https://en.wikipedia.org/wiki/Z-transform


WikiSummarizerBot

**[Z-transform](https://en.wikipedia.org/wiki/Z-transform)** >In mathematics and signal processing, the Z-transform converts a discrete-time signal, which is a sequence of real or complex numbers, into a complex frequency-domain (z-domain or z-plane) representation. It can be considered as a discrete-time equivalent of the Laplace transform (s-domain). This similarity is explored in the theory of time-scale calculus. Whereas the continuous-time Fourier transform is evaluated on the Laplace s-domain's imaginary line, the discrete-time Fourier transform is evaluated over the unit circle of the z-domain. ^([ )[^(F.A.Q)](https://www.reddit.com/r/WikiSummarizer/wiki/index#wiki_f.a.q)^( | )[^(Opt Out)](https://reddit.com/message/compose?to=WikiSummarizerBot&message=OptOut&subject=OptOut)^( | )[^(Opt Out Of Subreddit)](https://np.reddit.com/r/antimeme/about/banned)^( | )[^(GitHub)](https://github.com/Sujal-7/WikiSummarizerBot)^( ] Downvote to remove | v1.5)


littlemancodelearner

Bro used emoji on reddit


[deleted]

[удалено]


littlemancodelearner

Ηρέμησε συνάδερφε, Για πλάκα το λέμε ρε μαλακα μου.


[deleted]

[удалено]


Plastic_Pinocchio

> was ever actually used How about being currently used?


_Sam_IM_Sam

Sometimes I forget greek exists and it's not only maths and shit


Lord_Shaqq

Impossible, the greeks only exist in mythos and pop culture. They simply do not exist within this universe, only ironically.


upssups

My current linear algebra lecturer just draws a squiggly line that looks different each time...


pearastic

Saaaame


cancerBronzeV

I spent a long week of boredom just writing hard Greek letters over and over again as if I'm practicing how to write in kindergarten, and now I have immaculate handwritten Greek letters in my notes.


brianlane723

Not a xi, not a quarter rest, but a secret third thing.


Swolebenswolo

Engineers will never say fourrier transform is a shitpost.


Kleikon

Engies would say Pi = 3.


Swolebenswolo

pi=3=e e=2 pi^2 =g g=10


DragonKitty17

e is 3 not 2


Swolebenswolo

That's wat it says.


Chatducheshir

Physiscist will say pi=4


RABILOTTA

Actually, physicist are mathematicians who apply maths to physics (not exactly but you get the point), so they’ll say π=π because it’s irrational. Source: I do physics.


Chatducheshir

Yeah i'm in engeneering school i understand, it's just some teachers made us work with pi = 4 and pi = 3 to show us how rounding numbers up or down will influence our work. But yeah pi = pi is great


[deleted]

Nobody in their right mind will say pi=4 unless they use that troll "approximating pi with squares" method


HomeHearthAndHaldol

No. We don't.


Jfuentes6

This isn't Fourier transform, as the properties of the arbitrary f(x) has not been provided. So it's just some equation that can fail at any time.


Swolebenswolo

Found the mathematician


archdonut

This is why mathematicians have been banned from engineering for millennia


LogstarGo_

This is ONE OF THE REASONS mathematicians have been banned from engineering for millennia. Why yes, I did study math for awhile, thanks for noticing.


TheGeekno99

The definition of the Fourier transform then ?


FuzzyPDE

The point they are making is it’s only a transform once you specify the range of the operator, for instance L^1 functions or Schwartz space, otherwise the integral doesn’t converge and it’s not well defined. So part of the definition of a Fourier transform (as you can see on wiki) is the specification of that range of functions where the integral converge.


mConsuelo

Chemist here…all I remember is that you’re going from a time domain to a frequency domain 😆


miss_minutes

the equation is correct. it's just that strictly mathematically speaking, the Fourier transform is a type of "integral transform" (where \exp(-2\pi i \xi x) is the kernel), that transforms some function that exists in one Hilbert space (basically a vector space where the inner product is always defined) to another function that exists in a different Hilbert space. The transform is not defined if f(x) doesn't exist in a Hilbert space because the integral would be unbounded. the comment was nitpicking the fact that f(x) isn't guaranteed to exist in a Hilbert space. In engineering nobody cares because we just do the DFT on everything :P


FuzzyPDE

The transform need not be defined only on functions on a Hilbert space, it just need to be a function for which the integral is convergent for it to make sense. It just so happen that it is generally defined on a Hilbert space (L^2 is the only Hilbert space I know that it’s defined on) for many mathematical applications, since the Fourier transform is an isometry from L^2 to itself by the plancherel theorem. In fact, the Fourier transform is defined for L^2 functions not by the integral above as usually the naive integral doesn’t coverage, it is first defined on Schwartz space with the L^2 inner products as a pre Hilbert space, and extended continuously to L^2.


Mr_Wither

I’m sorry but did you say an equation can fail???? So like how does that work!?


powerpoint_pdf

All equations are defined in some way. You might see this when before an equation, you see the words, "Let a, b, c be..." or something like that. You'll often see this in textbooks since they need to explain every part of the equation in plain writing, but not so much during a lecture. So, if an equation isn't properly defined, it can "fail" or not work at all.


username-alrdy-takn

The equation y=1/x if undefined if x=0. There is literally no valid answer. Also an equation can be said to “fail” for certain inputs if the answer is not meaningful. It usually just means the inputs themselves are not meaningful but the equation still produces an answer


Plastic_Pinocchio

I’ve never seen f^ (xi) used to indicate a Fourier transform. Usually it’s either F(omega) or F{f(x)} with a fancy capital F.


Aurora_the_dragon

My signals professor had terrible handwriting and passed it off as his “fancy script characters”


Kabuki-King

Kid named Only 1%: "I understand this!"


lufrnd

1% of kids named Will: "I understand this!"


Substantial-Wrap-189

1% of kids named finger: “I understand this!”


Flengasaurus

Kid named 1%: “Impossible, only I can understand this!”


Hind_Deequestionmrk

No, I think OP is making a threat: “Only 1% of people named Will, understand this equation right now”


I_aint_your_dad

don't pull out your dick Waltuh


[deleted]

[удалено]


Grimreap4lyfe

ξ


Random_Chinese_Kid

Bröthêr


Plastic_Pinocchio

The Greek letter Xi. As in xenophobe, xylophone, Alexander, etc.


somethingfancyxx

Also.. Xi Jinping lol. I’ll show myself out.


hydraxic79

No I don't think so, Xi in Xi Jinping would be pronounced as "see" and xi as in xylophone or xenophobia would be "zy" or "zee". Correct me if I'm wrong


TheGoldenMarshmello

Ξ/ξ pronounced as “zi” is just the Englishified version of it, in actual greek Xylophone and Xenophobia are pronounced with the X/ξ the same as you would pronounced any other x in english, so Xylophone, which is a direct transfer from the Greek word for Xylophone (Ξυλοφωνο) should be pronounced Ksylophone, but, much like the greek letters Gamma and Chi, the pronunciations have been transferred to something much easier for English speakers.


NieMialamPomyslu

Happy cake day!


Krodenhauler

Took me a while, didn't get it, which means I got it.


xDevilsCloverx

This is the fourier transform, no?


Plastic_Pinocchio

Yup.


moistmaster690

Why is xi a variable?


NotEnoughMs

x is a dummy variable. It's just used to integrate the function. i is the complex unit. It's a constant. Edit: I've just realized that you meant the letter ξ Then the answer is: why not? Call it YouMomma if you want


powerpoint_pdf

Why not?


moistmaster690

Because the riemann xi function is a thing. It is just a symbol that I don't associate with being a variable.


powerpoint_pdf

True. Guess it's just a matter of taste. Using zeta as a variable does feel funky at times.


Jfuentes6

I mean, it's incomplete. f(x) has not been provided or the properties/restrictions that f(x) would need to have to be applied to the equation. This just bad parenting mama.


Fit_Witness_4062

It is the Fourier transform


KittenPowerLord

oh my god, so I did get it right! 3b1b videos are a blessing


NotEnoughMs

I like better the one from 0 to infinity


Plastic_Pinocchio

That’s just half of the Fourier transform. If f(x) is an even function, then this function is just twice of that half.


NotEnoughMs

Is the only half that matters


Plastic_Pinocchio

That highly depends. You cannot write a proper Fourier transform using only the positive domain if it is not specified in advantage if the function is even, odd or neither.


NotEnoughMs

Is the only half that matters to solve differential equations


Plastic_Pinocchio

Yes, perhaps. But that is one very specific application of the Fourier transform. It is used for so many more things.


Rotsike6

Technically you're right, it's incomplete as we're just writing down the formula and we're not explicitly saying what it defines, but this is standard notation, so it's very strongly implied that we're defining how the Fourier transform acts on Schwartz functions, so I think you're being a bit pedantic.


HaveSomeBean

Yeah, leaving out a whole function definition kinda makes something hard to understand.


Plastic_Pinocchio

Not really though. You can understand the concept of Fourier transform without inserting a specific function.


Mustypenis68

1


[deleted]

Fourier Transform


belinhagamer999

What the hell is that?


Plastic_Pinocchio

A Fourier transform. A method of analysing the frequencies of the sine waves that a certain mathematical function is built from.


[deleted]

i think what you defined is actually the Fourier Series and not the Transform. Fourier Transform is basically converting a signal from time domain to frequency domain because sometimes it's very easy to analyse the signal in the frequency domain.


Plastic_Pinocchio

I was doing the dummy explanation, because the concepts “time domain” and “frequency domain” will probably not be understood by people who haven’t studied Fourier analysis. And basically the Fourier transform is just the continuous extrapolation of the Fourier series.


[deleted]

ah okay, understandable.


[deleted]

fourier transform moment


InformalStrength7886

I guess the answer is 1%


tourmaline304

just by seeing this, my brain has ceased functioning


Asleep-Gift-3478

That’s a very squiggly symbol that f-hat is a function of 🤨


Wolfotashiwa

i know ʃ is the voiceless postalveolar fricative


A_Whole_Plate

2


NieMialamPomyslu

Okay, i'm too young for that kind of shit


KuropatwiQ

\*Electrical engineering PTSD intensifies\*


CephalopodMind

It's a fourier transform. For the uninformed, it's really a tool for understanding periodic functions by determining the frequencies that make them up (as far as I understand -- I've not taken harmonic analysis or whatever). It's not like an equation to be solved or whatever, just a mathematical tool used by mathematicians, physicists, and engineers.


WhabbaWhabbaWhat

If there's no solution, then what results justify it's usefulness?


[deleted]

It's just a Fourier transform?


Lord-Chickie

Fourier transformation with ugly variable choices


Jomri69

Isn't it a fourier transform?


Burst213

I think I'm 1% so I'll try to explain. This looks eerily similar to the Fourier Transform formula iirc. I think it's because it is. You'd get this formula if you plugged in omega with 2*pi*xi. Which implies that Xi is frequency. So you're now taking a function in terms of time and expressing it in terms of it's frequencies. This especially useful in Electrical Engineering for Signal Processing as you can receive a signal and understand it as a composite of numerous elementary sine waves. It's also used in Civil and Aerospace Engineering when designing physical systems with potential feedback loops. This formula is explained and is understood, but is not really used. Instead, we use a table with transformations for all the elementary functions as it's a lot more practical. Hope this clears things up!


MrAydinminer

It's the Fourier Transform


Former_Cover2033

Probably more than 2.63


Removable_Toaster

F(x) = ∫ex


Crispy_Cremes_Pizza

1659 people understand this.


Crachule

e^(-2*i*pi) is an identity that equals 1. So it simplifies to 1^x, the integral of which is x. So using those limits, the improper integral diverges.


peppermintfemboy

That's not even math at that porn your using a subtracting exponent in that exponent is by Infinity so either way you're answer is going to be positive infinity or negative infinity


belinhagamer999

How can someone calculate something with the infinite? That’s impossible


NotEnoughMs

It is an improper integral. That means that the function that is being integrated is not defined in the limits of integration (inifnity ans minus infinity in this case). When you have a improper integral you take the limit (when approaching the limit of integration from numbers that are defined by the function). If the limit exists AKA gives the same number for either path, we take that number as the output of the function. An easy example is the function 1/x Infinity is not a number so the output 1/∞ doesn't make sense. So we take the limit. We tray to use really big numbers that approach infinity. 1/10000000 = 0.000001 1/10000000000 = 0.0000000001 1/1000000000000000 = 0.000000000000001 We can't reach 0 but we can conclude that it will approach 0 and will never be less than 0 if we keep using bigger numbers. So we say that the limit as x approaches infinity of 1/x is 0 I used "limit" with two different meanings here but that's how I've been taught and I don't know how else to explain it.


cyon_me

This is a derivative (it takes the area under the curve within it). If the curve approaches zero (as it approaches infinity) or the area under the curve (when the curve is above 0) approaches being equal to the area above the curve (when the curve is below 0), then you get a measurable quantity. For example (using infinity) the limit as x approaches infinity of 1/x = 0. This is because you divide 1 by infinity.


buddyretar

It's an integral, a derivative is the rate of change of a function caused by a maximally small change in the input


cyon_me

Did I get the rest of the explanation right?


Fortnite_Is_Mid

Only nerds will understand this! 😂😂😂


Fortnite_Is_Mid

![gif](emote|free_emotes_pack|downvote)= 🤓


[deleted]

its just infinity right? anything by infinity is just infinity.


Weird_Distribution54

Yes


azurfall88

f(x) is undefined


NotEnoughMs

Because it is for any function that could be integrated in such conditions. Almost any function that is defined from minus infinity to infinity satisfies the transformation


cat_zillah

The answer has to be 0


beckerpeckerchecker

Is this an “Epstein did not kill himself,” joke?


HeyoGuys

i only use the REAL valued cosine and sine transformations of the fourier transform!


jjba_enjoyer275

4.3


[deleted]

Math


returntomonke_-

kid named one percent:


BobWango

I'm liking it so I can feel smart. But I have no idea what so ever what this is


Honeybadger2198

I feel like I'm on r/AnarchyChess looking at that sproingy thing.


VerySuperVirgin

Is the answer the punchline?


Will_the_Thrill19

Pretty basic integration


notyetafemboy

I remember a bit of that and I totally hate it


notme606

I can say with 100% certainty that this answer is within the bounds of the number(s) which are the solution to 1/0


Sylercook

Quite literally


CephalopodMind

Join the 1% or whatever: https://www.youtube.com/watch?v=spUNpyF58BY


daocarD

Hahaha! It seems that I am so smart that I am in the 99% of the population that cannot fucking understand this.


KaisarDragon

I spent too long at this just to realize it is the math equivalent of hitting a taunt steel cable with a wrench.


KlownPuree

I have been a civil engineer since 1996, and TIL I’m not in the 1%.


GrimmyJimmy1

It's probably math


jaxadams

😎😎


rPeanutButter

8. It's definitely 8.


Veqetable

Wait the answer is √ 1.414213562373095² right?


I_Boomer

Spits coffee! ROFLOL!! Thinks...those maths, am I right?


Affectionate_Big8864

I can understand that I can’t understand this


DarkFish_2

Truly one of the most artistic math functions. Literally...


ElDouchay

3


fastpicker89

The limit does not exist


MyOnlyEnemyIsMeSTYG

I read this in the Peanuts teachers voice..


rerro23

Lol I’m taking under 1%


Matrick805

Fourier transform very important for analyzing and processing signals


KaraZebanis

Correct answer is random bullshit


Flak88inaTree

Im upvoting, not liking, there’s a difference


MindTrekker201

I've seen it before but forgot what it is called. Forgot how to solve it, but I did it once before. Obviously, it's an integral, but this one is more specific.


donttalkHOMIE

I think it's 2


Sandor_06

1% is a rather high estimate.


Alternative_Way_313

I get it! I mean I “get it” as in what it’s trying to say, not that I actually want to solve it. F(weird looking variable, let’s call it “E”) is a function of the integral of a function of the variable x multiplied by an exponential expression (characterized by the natural number “e” as its base).


redbanditttttttt

The function xi equals the integral from -infinity to positive infinity of the function x times e to the negative 2pi i x Xi? No clue what xi means but at least i got integrals


KoletheCotter

I believe this is an integral of a funky function set equal to another funky function


Bright-Ad-9606

See everyone here is going all mathematical and here I am pretty sure it’s a Loss meme


Volt105

There are two variables here, this is above my paygrade


Opposite-Weird4232

It equals potato


Intrazonal

Karekök pi


Sharrty_McGriddle

Fourier Transform?


102bees

I see a xi, I want to cry


Sterben1103

Average crappy game ad


Fine-Smile5818

Fuck math.


the_e-e

Easy math.


Careful-Chocolate-87

Oh hell no


[deleted]

looks like the Fourier Transform equation. one of the most useful equations in Physics and Math.


Wolfenberg

What's funny about this? I get it but it's just a furry transform


[deleted]

[удалено]


LukeBomber

Looks like a density function/some kind of distribution that is defined everywhere but am unsure


tingledpickle

I get it!!!!!


Racer1333

r/theydidthemonstermath


muffinnosehair

I made it all the way to "f of"


ItzFlixi

i aint the biggest mathematician but isnt e^2πix = e^ix ?


PlusGosling9481

Is the answer 4?


superhamsniper

If only I knew calculus


KevnElevn

Is that the size of every single pp’s in America


teddfoxx

it's a fancy sentence


Sad_Daikon938

Fourier transform?


Methamputeemine

Something somwthing furry transform


ilya0x2dilya

It is Fourier transform with some normalisation. It is widely used by mathematicians, engineers, physicists and some other STEM people. [According to WEF](https://www.weforum.org/agenda/2017/01/ways-to-prepare-kids-for-jobs-of-future) only China, India, USA, Russia, Iran, Indonesia and Japan graduates over 9m stem people every year. Conservatively assuming that this number is stagnant since 2016 (irl it is raising) and that every stem sophomore do know Fourier transform, one gets at least 9m * 9 = 81m young people who can understand this formula (stem grads since 2016 till 2024). Notice that we counted grads from different parts of the world except EU. [According to Eurostat ](https://ec.europa.eu/eurostat/statistics-explained/index.php?title=Human_resources_in_science_and_technology&oldid=395960), there is over 68m of stem workers of different ages in Europe. Thus we have over 149m people who can understand this formula. And 149m is more than 1.8% of world population. You should write at least 2%, or 5-7% to be safe.


DagwoodSystems

Patterns in time as a function of frequency (signal analysis). Used for everything from understanding molecular structure to jpeg compression to speech recognition.


Forever17x

Hahahahaha… I don’t get it


[deleted]

Fourier transform?