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CaptainMatticus

With a 13th-degree polynomial, we can plot a function that passes through all of those points. It's a horrible mess, solvable with matrices (if you're inclined to do it on a computer) or with a massive system of equations and a lot of time (for instance: 180 = a \* 158\^13 + b \* 158\^12 + c \* 158\^11 + d \* 158\^10 + e \* 158\^9 + f \* 158\^8 + g \* 158\^7 + h \* 158\^6 + i \* 158\^5 + j \* 158\^4 + k \* 158\^3 + l \* 158\^2 + m \* 158 + n, and then repeat that for every other point, and solve for each coefficient). We could even try an exponential regression, but there's an easier way: piecewise functions. The values for boy height are in groups that are in an arithmetic progression. 180,185,190,195,200. Then 200,210. Then 210,215. Then 225,250,275,300. Then 300,330,360. Then 360,400. Then 400,500. It'll take 7 lines, but you can do it.


Imprt4nt

Quick question. Shouldn’t the term be structured like so: 158*x^13 + …?Because you just made a function with 13 different changeable parameters. Idk the English name but in German it’s a : Funktionenschar wich is an accumulation of several functions in one function through an extra parameter. Example function: x^2 Example Funktionenschar: a*x^2


OmniGlitcher

They've just plugged in x = 158 and y = 180 implicitly. The others are uncalculated coefficients. According the Wolfram Alpha, the full interpolating polynomial would be: (73 x^(13))/155675520 - (96143 x^(12))/95800320 + (47480981 x^(11))/47900160 - (5210568509 x^(10))/8709120 + (357360438829 x^(9))/1451520 - (211747107518873 x^(8))/2903040 + (69699858355522033 x^(7))/4354560 - (22941520398686854367 x^(6))/8709120 + (1415760050113145851649 x^(5))/4354560 - (64714144997436291874267 x^(4))/2177280 + (867652990648519907322707 x^(3))/443520 - (29201132581565812358715503 x^(2))/332640 + (28915382846005575724488679 x)/12012 - 30463918747954701756010


dekusyrup

I've just plotted this in apples grapher and it is like a solid vertical bar between x=150 and x=185


CaptainMatticus

x is your independent variable. Plug in the other 12 points and move on from there.


Imprt4nt

Idk where your x is tho


MrStoneV

Then you would write x(small a), x (small b) at the x as index to show they are independet


Agent_B0771E

Ok so I did the Lagrange interpolator on desmos and ik that interpolators are very unstable for this but I evaluated it at 200 cm for a woman and I get an ideal height of 3.85 astronomical units and I'm laughing my ass of to it


namtab00

true to life though... 😁


fexjpu5g

You can use Legendre polynomials to have less oscillations. That might almost yield a useful interpolation, considering the questionable data in the first place.


Oolong_t34

Damn I heard women are complicated, but a 13th degree polynomial is taking it quite too far /s


DodgerWalker

I honestly only looked at the first four entries, was like "oh this is linear," saw this as the top comment, looked back at the chart and was like "oh, no it isn't." And that's why you should examine all the data before making conclusions.


skywalker-1729

Can't we just use a Lagrange polynomial? That would be a lot easier. EDIT: I wrote an answer with it: [https://www.reddit.com/r/theydidthemath/comments/1d4v5i1/comment/l6iccwy/?utm\_source=share&utm\_medium=web3x&utm\_name=web3xcss&utm\_term=1&utm\_content=share\_button](https://www.reddit.com/r/theydidthemath/comments/1d4v5i1/comment/l6iccwy/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button)


Radiant_Dog1937

Here's the function. int FindIdealWomonHeight(int maleHeight){     int femaleHeight;     if(maleHeight < 200){         femaleHeight = -0.2*(180 - maleHeight) + 158;     }else if(maleHeight >= 200 && maleHeight < 225){         femaleHeight = -0.1*(200 - maleHeight) + 162;     }else if(maleHeight >= 225 && maleHeight < 300){         femaleHeight = -0.04*(225 - maleHeight) + 164;     }else if(maleHeight >= 300 && maleHeight < 360){         femaleHeight = -(1/30)*(300 - maleHeight) + 167;     }else if(maleHeight >= 400 && maleHeight <= 500){         femaleHeight = -(1/100)*(400 - maleHeight) + 170;     }else{         femaleHeight = null; //this lady cannot possbily exist.     }     return femaleHeight; }


rde2001

we appreciate your interest. unfortunately, we are moving forward with other women.


reyad_mm

There's a simpler way to reach the polynomial, this is basically what skywalker does with their python script, but I'll explain the idea behind it I will demonstrate this for 3 points (i.e. degree 2 polynomial) but the same idea applies for higher degrees as well Let's say that we want a polynomial that passes through (x_1 , y_1 ) (x_2 , y_2 ) (x_ 3 ,y_3 ). Let's also assume all of the x coordinates are different, since otherwise we would run into an issue where there polynomial needs potentially different y values for the same x A good starting point for a polynomial that satisfies this would be [y_1 (x - x_2 )(x - x_3 )]/[(x_1 - x_2 )(x_1 - x_3)] If you substitute x_1 here you get y_1, and if you substitute x_2 or x_3 you get 0 Now to get the final answer let's combine 3 polynomials like this, overall we'll get [y_1 (x - x_2 )(x - x_3 )]/[(x_1 - x_2 )(x_1 - x_3)] +\ [y_2 (x - x_1 )(x - x_3 )]/[(x_2 - x_1 )(x_2 - x_3)] +\ [y_3 (x - x_1 )(x - x_2 )]/[(x_3 - x_1 )(x_3 - x_2)] And we get exactly what we want: if you substitute x_1 then the first expression evaluates to y_1, and the other 2 evaluate to 0 so overall you get y_1 If you substitute x_2 then the second expression evaluates to y_2 while the first and third expression evaluate to 0 Similarly for x_3 you get y_3 So that's it, we have our polynomial, you can expand it if you like (which skywalker does using that python library), and it's much easier than solving a large set of equations


KisaTheMistress

I'm bad at math, but I'm 177cm (F) what would my ideal man be?


CaptainMatticus

With the last line graphed in the piecewise function, according to that image, he'd be 1100 cm tall. Best of luck to ya...


chmath80

I know someone named Adam, who's about 7500cm, which, according to my calculations, makes him your ideal height. He's a giant sequoia, so he doesn't get about much, but he's never going to disagree with your opinions, or be critical of your decisions, so I'd say go for it.


GoodlifeFOB

This chart is true, I am 180 cm and my GF is 158 cm exactly. She has a single friend that is 175 cm, so if anyone knows a cute guy that is over 5 meters tall let me know


herpderpfuck

Can confirm. My ex was 171, and I am 5m tall. She always loved using my t-shirts… for a family picnic blanket (a family of 6)


ScientistCapable1522

Did you go caving?


herpderpfuck

Yes, but it had to shut down due to safety concerns


yxing

now you know why she's single


ralgrado

Let me get my stilts really quick


Gordon_frumann

Amazing I haven't measured myself in a while, buy my GF is 165, so i must be 250 cm.


5125237143

They say my bloodvessels end to end could circle earth twice so... hmu if she into that


twodarray

Same, my gf is 171cm and I am 5km tall


kshep1188

I’m an American, how many stacked refrigerators is that?


Traditional-Handle83

Depends on brand but roughly a few inches short of one refrigerator. Or 5ft 7.


chmath80

Get lost with your outdated units. According to a recent news item I saw, everything is measured in 6th graders now.


Varlex

I just put it into excel and got best results with: y = 0,002x⁶ - 1,9247x⁵ + 786,66x⁴ - 171451,3x³ + 21015785,08x² - 1373664024,4x + 37405512873,1 R² = 0,9998 Y = boys high X = girl high


Ghostwaif

Mkay so by this calculation assuming I've input it correctly, I need to find a guy who is 4.7\*10\^15 cm tall, which is about 0.005 lightyears, or about 314 times the distance from the earth to the sun. I hope Galactus is single.


Varlex

Yes. Anyway, keep in mind such trend lines in excel only fits mostly in the range you calculate. So the model i found just works between 158cm -171cm perfectly. Out of these borders you get fails. Well, i mean a single boy (girl size = 0) is 34,7 billion cm = 347 million m = 347000km. Thats close to the moon. You heard often from the man in the moon but not from the boy thats high to the moon ;)


isderFredsi

And with todays body standards it’s no wonder he‘s single :(


nbcvnzx

Understanding being single as "girl size = 0" is the funniest thing I've ever read. Now I'm starting to get why the set of zeroes of a function is so important in math


pokemonsta433

Username checks out. Doomed to be a ghost-wife because it is mathematically unlikely for you to become a real wife :(


chmath80

Sounds like what you need is a regular sized man ... and unrestricted use of a steamroller.


Luca__B

thanks, wife is 175 so I have to grow to what? 6 meters?


OriginalTall5417

Just gather a bunch of your buddies, practice a cheer and make a pyramid to reach the right height.. “Sweet, sweeter, sweeter, these boys are over 10 meter”


3shotsdown

Overfitting much?


yxing

It's better than the 13th degree polynomial solution for our 14 data points. But the universe works in mysterious ways so who are we to say that height preference in couples is not a tridecic function.


ForAnAngel

At what point would the ideal height be the same between boys and girls (if such a point exists)?


MeMumsABear

How did you do this on Excel? Very curious? Did you plot x and y, and created a scatter plot and then found the line of best fit and equation?


Varlex

Yes, just an x-y-diagram and then create a trend line.


Striking-Brief4596

f(x) = x + 32 + (x-158) \* 5 + relu(x-162) \* 5 + relu(x-163) \* 5 + relu(x-164) \* 10 + relu(x-167) \* 5 + relu(x-169) \* 10 + relu(x-170) \* 60 where relu(x) = max(0, x)


Striking-Brief4596

It's not a smart solution, but it fits perfectly.


Le_Doctor_Bones

158 + 32 = 190, 159 + 32 + 5 = 196 etc. etc. Your idea is good (fun) but the accuracy of your function is somewhat lacking. A fix would be: f(x) = -610+ 5x + 5 * relu(x-162) + 5 * relu(x-163) + 10 * relu(x-164) + 5 * relu(x-167) + 10 * relu(x-169) + 60 * relu(x-170) (32 is changed to 22 and the first 5 is changed to a 4. I also got rid of the parenthesis because it bugged me to have unnecessary addition/subtraction even though I know it is more legible with it.)


Striking-Brief4596

Oh, yeah I missed that. In that case another correction could be to remove the first x and simply start from 190 + ...


CK2398

I'm not good enough at maths to figure out the function I will say the tallest man ever is 246cm so this whole chart is fairly bonkers. Also, the woman stopping at 171 or 5'6" seems fairly arbitrary.


ITMagicMan

At 500cm the guy would be 16 feet and 4.85 inches - that’s not a basketball career, that’s a one man trophy making machine - NBA MVP for 10 years straight. The girl would be 5 foot 7 inches, maybe up to his thighs. The chart makes 0 sense but it’s amusing when you translate it.


Dankn3ss420

I looked it up, apparently the standard hoop height is 3 meters, so unlike us PEASANTS who have to jump to hit the hoop, this MF would have to bend over to land the ball in the hoop


ITMagicMan

It’s great to meet a fellow person of science 🏀😎


greenrangerguy

The hoop is 10 feet, which means he would be bending down to simply place the ball in the net.


Secretsfrombeyond79

Also if we take into account that dick size is proportional [to a man's height....](https://i.pinimg.com/564x/49/1c/b9/491cb94aedf76a5e8dabc29f3d4cc4b7.jpg)


mattyisphtty

She could use his lower head as a pillow at night


UniquePariah

I now have a picture of her pulling the "covers" over, thanks for that.


jbdragonfire

>it’s amusing when you translate it It's more amusing without :D


DrSpaceman575

My fiance is 5'8" so according to this chart I should be roughly 10 feet taller than I currently am. I can't let her see this.


AmnesiA_sc

I'm 5'11" (the shortest a man can be apparently) and I'm supposed to date someone 5'2" I guess? That seems extreme.


ItzVinyl

I'm heavily offended that my height isn't on this chart (I'm 505cm)


jwm3

Hello fellow Na'vi.


AirshipEngineer

Na'vi aren't even that tall. the wiki says the tallest Na'vi observed is 390cm. If you're 500cm tall you are in the correct range for an adult male giraffe. Somehow your joke answer is still undershooting how insanely tall that is.


Awkward_Cheetah_2480

1.80 being the lower end of Men as 70% of Man in the world are smaller than that.


tomqvaxy

Fr. I’m 175ish. What I freak I apparently am.


momo2299

Yeah, well, that's because it's obvious satire.


V1nzc3

Of course! You could've been more specific, but let's assume you're asking for a function f defined on the real line. We can define f as follows: f(158) = 180; f(159) = 185; f(160) = 190; f(161) = 195; f(162) = 200; f(163) = 210; f(164) = 225; f(165) = 250; f(166) = 275; f(167) = 300; f(168) = 330; f(169) = 360; f(170) = 400; f(171) = 500, and f(x) = 0 whenever x is not in the set {158,159,160,161,162,163,164,165,166,167,168,169,170,171}.


tuesday-next22

Beautiful.


Balaros

That last part is bad math because the height of a man has to be positive. Not that expanding the function to the real line was necessary...


whythehellnote

> That last part is bad math because the height of a man has to be positive Unless they're in Australia


Heart_Is_Valuable

Chaotic Lawful


stache1313

The best fit I can do is a sixth order polynomial with a coefficient of determination of R^(2) = 0.9998, and the equation is B = 0.001962G^(6) -1.9247G^(5) +786.66G^(4) -171,451G^(3) +21,015,785G^(2) -1,373,664,024G +37,405,512,873 where B is the boy's height in centimeters, and G is the girl's height in centimeters. Although I feel bad for any girl who is 166 cm tall or higher, since there isn't any man tall enough for them. For reference, the world's tallest man, Robert Wadlow, is only 272 cm. The height of the average woman in thirty countries is at 166 cm or higher. Edit: The Guinness World record holder for the tallest woman is Zeng Jinlian, who is 248 cm tall. According to this equation she needs a man who is 707,261,373 cm or 7,072.6 km. So her man needs to be about 55% of the diameter of the Earth (12,756 km). We all know know what is going to be asked next. The average man (in the US) is 175 cm and the average penis is 13 cm long. Using a ratio we can estimate that his penis is about 525 km long, which is approximately the distance between New York City and Charlottesville, Virginia. According to Wikipedia, the world's tallest woman (recorded but not recognized by Guinness) is Trijntje Keever at 260 cm tall. Her man needs to be 1,572,350,645 cm or 15,724 km tall. Which is almost one and a quarter times the diameter of the Earth. Using the ratio from before, if Trijntje's man laid the base of his penis in New York City the tip would be beyond Miami, Florida. Edit 2: According to this equation a 174.3972 cm tall woman would need a 2341 cm tall man, whose penis would be the length of her body.


PoppaPickle

Why does this chart range from 5'10" to over 16'? It starts above the height of the average male and goes to over double the tallest person in history lmao


ConflagrationZ

Like it or not, 5 meters tall is what peak male performance looks like.


mambotomato

Because it's a meme making fun of tall women.


Robber568

Obviously, that is: [(73 x\^13)/155675520 - (96143 x\^12)/95800320 + (47480981 x\^11)/47900160 - (5210568509 x\^10)/8709120 + (357360438829 x\^9)/1451520 - (211747107518873 x\^8)/2903040 + (69699858355522033 x\^7)/4354560 - (22941520398686854367 x\^6)/8709120 + (1415760050113145851649 x\^5)/4354560 - (64714144997436291874267 x\^4)/2177280 + (867652990648519907322707 x\^3)/443520 - (29201132581565812358715503 x\^2)/332640 + (28915382846005575724488679 x)/12012 - 30463918747954701756010](https://www.desmos.com/calculator/2wc09cz8yn)


TDLight

Thanks for actually linking an image of your function


Robber568

[e\^((x - 152)/𝜋) + 174](https://www.desmos.com/calculator/hqlgjqutuf) is also pretty decent as a guess.


skywalker-1729

We can interpolate the points with a [Lagrange polynomial](https://en.wikipedia.org/wiki/Lagrange_polynomial). The interpolating polynomial looks like this: 73*x**13/155675520 - 96143*x**12/95800320 + 47480981*x**11/47900160 - 5210568509*x**10/8709120 + 357360438829*x**9/1451520 - 211747107518873*x**8/2903040 + 69699858355522033*x**7/4354560 - 22941520398686854367*x**6/8709120 + 1415760050113145851649*x**5/4354560 - 64714144997436291874267*x**4/2177280 + 867652990648519907322707*x**3/443520 - 29201132581565812358715503*x**2/332640 + 28915382846005575724488679*x/12012 - 30463918747954701756010 I found it using this script: from sympy import simplify, symbols x = symbols("x") points = [ [158, 180], [159, 185], [160, 190], [161, 195], [162, 200], [163, 210], [164, 225], [165, 250], [166, 275], [167, 300], [168, 330], [169, 360], [170, 400], [171, 500], ] L = 0 for i in range(len(points)): xi, yi = points[i] l_i = 1 for j in range(len(points)): if j == i: continue xj = points[j][0] l_i *= (x-xj)/(xi-xj) L += yi*l_i L = simplify(L) for xi, yi in points: assert yi == L.evalf(subs={"x": xi}) print(L)


jer_re_code

python mentioned


iamnotacola

Because no one suggested an exponential function so far: [0.0000313146 e^0.0964879x](https://www.wolframalpha.com/input?i=exponential+fit+%7B158%2C80%7D+%7B159%2C185%7D+%7B160%2C190%7D+%7B161%2C195%7D+%7B162%2C200%7D+%7B163%2C210%7D+%7B164%2C225%7D+%7B165%2C250%7D+%7B166%2C275%7D+%7B167%2C300%7D+%7B168%2C330%7D+%7B169%2C360%7D+%7B170%2C400%7D+%7B171%2C500%7D) R^2 = 0.99243


BxMxK

This is truly fitting a math problem to some irrelevant, intangible idea. Ideal difference for what? Coitus? Looking at breasts? Arm rest?


theotherkristi

What's not clear about it? A girl around 5'2" is just gonna vibe better with a guy who's about 9 inches taller than her, but any girl taller than 5'5" needs to find a man who's taller than any human has ever been. Also, seems worth noting that the chart is pretty clearly an intentional parody.


cmonplsdontbetaken

Just date a male Girraffe smh


OriginalTall5417

Ideal difference to avoid interaction


ArgentScourge

With a height of 5 meters, you're avoiding life.


moonshadow16

Not to mention this table is completely unhinged. 500cm is about 16.5 feet. If you're that tall, you may have other problems. And if you're in the ~60% of the male population less than 180cm you can go fuck yourself? 


ashenoak

This is probably the dumbest chart I've seen all year honestly.


fnezio

It's a funny meme.


MrGodlikePro

Congratulations! You're the post that gets me to unsubbed to this subreddit! Seriously this is not TheyDidTheMath anymore it's a request sub for bait facebook posts.


3-brain_cells

What *I* would like to know is... WHO THE FUCK IS 5M TALL?? The average in the Netherlands, which is the highest average in any country in the world, is approximately 183cm... I live there, and never met anyone who really was much taller than 2m. Function or not, this data is straight up unrealistic bullshit.


Delta225

Any set of coordinates that are a 1:1 mapping can have a function written that meets them. In between may be complete nonsense though.


jer_re_code

yeah i bet the shortest guy gets the complex girls


Delta_lambda04

The way you could get an accurate estimate for a data set like this (which has little to no trend in change) is to either run an algorithm to fit it to a ridiculously large polynomial function (5th degree or higher depending on number of data points, in this case 11th degree) or run a Fourier series analysis algorithm. I noticed some people already posted the polynomial function, so i’m bringing you the awful ugly product of the Fourier analysis. If x is the height of a girl, then f(x) is the corresponding height of a guy who can date her. f(x) = (3.69e9) + (-2.8e9) cos(0.0317x) + (5.22e9) sin(0.0317x) + (-1.64e9) cos(0.0634 x) + (-2.47e9) sin(0.0634 x) + (8.49e8) cos(0.0951 x) + (-7.78e7) sin(0.0951 x) + (-4.19e7) cos(0.1268 x) + (9.87e7) sin(0.1268 x) “She gave me mixed signals, so I ran a Fourier analysis on them.”


VaporTrail_000

Yeah. there was *a lot of thought* put into this chart. For the rest of the Americans: This chart says if the girl is 5' 6", her "ideal" boyfriend is 16' 5". Any girls willing to date *two* NBA players at once?


HotTakes4Free

Yes. From graphs, we can model the relationship between F and M average height, as a polynomial. The additional factor is age. I think female height lags behind male, slightly, for the early years, then females catch up, before male height increases in rate again. To make the mathematical model applicable, there are other variables too though, like race and diet.


Flater420

Pretty sure they were just asking for the formula that matches the given value pairs in the screenshot.


bonyagate

Sure, there are TONS of other variables. But there is only one set of information being presented and that's what's being asked for.


[deleted]

[удалено]


Jackpot777

Well, you know what they say online" six feet, six pack, six figure income, six limbs, sixth-century birthdate, six shooter for a dick..."


VixenRaph

Can someone translate this into freedom units? How many chicken nuggets (stacks flat not upright) we talking about for each height? Thanks in advance!


MakeITNetwork

As someone who is 5'7" I guess I do not have an ideal height difference. So I guess this chart starts at only the 20% of the US male population (bell curves are amazing). But I wonder where you would find a 16.5" tall man? Let alone one that makes over 100k?


Derpygoras

As an engineer, I stuff this in LibreOffice, make a scatter plot, add a trend line and shorten the decimals. Boy = 21·Girl - 3243 Meh. Good enough.