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Let's talk about π.
LizFoster (118)

Today I'd like to teach you all about one of my all time favorite things: π!
Most likely, all of you know that π is the ratio of a circle's circumference to its diameter, and probably only know only 3 to 5 decimal digits of it. However, π is an irrational number, meaning it has no end! Let us go through all of the different formulae of π I have programmed, and explain what they mean! Let's dive in. (These are numbered in the order that they print when the attached code is run)

  1. The Monte Carlo Method

One way you can do this is by drawing a square, with a circle whose edges touch the 4 edges of that square within. Now imagine you were to draw many many dots randomly within the square-circle hybrid. If you take the number of points that fell within the circle, divide it by the total number of points, and multiply it by 4, you get (you guessed it) π!! More info can be found here:
https://ja.wikipedia.org/wiki/モンテカルロ法

  1. The Chudnovsky Algorithm

This is one of the fastest methods out there, being used in the world record, to calculate 50 trillion digits of π! I already explained it in a previous post, but the formula (and more cool information!) is here:
https://ja.wikipedia.org/wiki/モンテカルロ法

  1. The Basel Problem

This problem, posed by a man named Pietro Mengoli, asked for the exact sum of an infinite series, with proof. Mathematician Leonhard Euler answered this, with proof, finding it to equal exactly π^2/6. Further info and interesting facts here:
https://ja.wikipedia.org/wiki/バーゼル問題

  1. The Wallis Product

Unlike the other formulae here, this one uses the Product Operator in its equation. If repeated over an infinite number of times, it will equal π/2. More information here:
https://ja.wikipedia.org/wiki/ウォリス積

  1. The Leibniz Formula

Last but certainly not least, I have here probably one of the slowest π-convergent methods out there. In fact, to get π accurately to 10 decimal places takes about 5 billion iterations, according to the Wikipedia page! This formula alternates between adding and subtracting fractions with odd denominators (meaning this is an example of an alternating series), and converges on π/4. For extra information, go here:
https://ja.wikipedia.org/wiki/ライプニッツの公式

I plan to make more π approximation programs in the future, so stay tuned if these kinds of things interest you as much as they interest me!

Thank you. ^ ^

Commentshotnewtop
nt998302 (98)

Sweet! I've been seeing your posts on these pi methods. This is awesome :)

LizFoster (118)

@nt998302 Thank you! I love doing this, it has become quite an enjoyable thing to work on in my free-time (coding and math, that is)

JosiahKnisely (24)

Wait, there are different numbers for π? This is when the confusion sets in...

JosiahKnisely (24)

I'm also very young. I don't get these things.

LizFoster (118)

@JosiahKnisely Oh, that's alright. I can explain. ^ ^

No, there are not multiple values for π. There is only one, that being '3.14159...' and so on. These are merely methods of calculating π, albeit with varying amounts of accuracy at certain numbers of iterations.

π is quite interesting and cool, in that it can show up within the solutions to various mathematical problems that appear to have absolutely nothing to do with circles (at least at first glance)!

The things that the program displays are not π, in that, based on the accuracy I've asked for, the digits it shows aren't EXACTLY π.

For example, a common value that we use when approximating π is 22/7. This is only accurate to 3 digits (3.14), and even closer is 355/113, which is accurate to 7 digits (3.141592).

While they aren't equal to π, we often use them, since they are close enough to be somewhat useful for our purposes!

We don't know what π equals exactly, since it is infinitely long, but these equations can hep us learn more and more.

Here's a helpful link that non-math people can understand ^ ^

https://simple.wikipedia.org/wiki/Pi

LiamDonohue (167)

wow you beat me in only like number 5 on hot now lol

LiamDonohue (167)

tho im confused why is this in Japanese lol @LizFoster

LiamDonohue (167)

time to whip out google translate lol @LizFoster

LizFoster (118)

@LiamDonohue You mean for the Wikipedia links?

You know there are English versions... ^ ^*

LiamDonohue (167)

no the post program lol @LizFoster

LizFoster (118)

@LiamDonohue Oh, they're just the names of the methods, and the iterations the code goes through for each one. Nothing special.

enigma_dev (7038)

Great work Liz! Very, very interesting post about a very, very interesting number! I just gave you the conzent creator role, which marks creators who upload high quality content! Congratz

LizFoster (118)

@enigma_dev Oh, thank you! I really appreciate that, that is so awesome of you! Yeah, numbers like π really get me going in terms of conversation, they are just so beautiful!!

Highwayman (961)

Do you know anything about something called a spigot method/algorithm or something? I heard of them at some point, but I’m not entirely sure where or exactly how either...

LizFoster (118)

@Highwayman Oh! I completely forgot about those, but yes, I do know about Spigot Algorithms! They can be used to find mathematical constants, like π! This is an article I had bookmarked about that:
http://stanleyrabinowitz.com/bibliography/spigot.pdf

LizFoster (118)

@Highwayman Ha ha ha, yeah, it is nothing. (Lol)

I am a bit of a nerd when it comes to math-related subjects (as you can probably tell), so I have many articles like this waiting for use.. wwwwww

Highwayman (961)

@LizFoster ah yeah that’s kinda me with programming, I have too many books rn XS

LizFoster (118)

@Highwayman Hehehe, same here, I have many books on math I've been saving for a rainy day..
( . __ . * )

Unfortunately I don't have any books on Python or really programming in general (Lol)

Highwayman (961)

@LizFoster hmmmmmm I’d suggest one of my books but I’m pretty sure non of them are using python :(

LizFoster (118)

@Highwayman Awww, that's too bad.. (Lol)

Highwayman (961)

@LizFoster ... I saw you were talking about learning "one of the C languages" earlier? That’s what they are all in. I know it’s not my place or anything at all, but I really strongly suggest you do, it’s so awesome.

I’d suggest maybe checking out cryptography or maybe AI Books, those are pretty math heavy I think :P

LizFoster (118)

@Highwayman Ooh, you've got me excited now! I certainly will, then! Have you gotten any specific suggestions for books I should buy?

Highwayman (961)

@LizFoster ehhh No. :( again all my books are c++, but I bet if you just look it up you will find something pretty easily. At least from what I can remember it’s pretty easy to find(it was just too mathy for me, so I never saved it). There are also some things on ai in this learn section too actually, though of course that’ll be more starter stuff than any of the more exciting stuff.

Actually if you learn C++, I found this one a while back on Neural Networks:
http://www.ece.ubc.ca/~msucu/documents/programming/C++%20neural%20networks%20and%20fuzzy%20logic.pdf

I don’t know if it’s actually good I forget I haven’t picked it up in a while(again- too mathy for me I’m bad at math lol)

And then this one is on analyzing stream ciphers(which are really cool by the way)
http://www.cs.ru.nl/~rverdult/Introduction_to_Cryptanalysis-Attacking_Stream_Ciphers.pdf

Again these are kinda introductions and also just things I pulled from my library, so I don’t how good they are but I hope they are helpful. :P

LizFoster (118)

@Highwayman Oh, nice! These look interesting, I'll start reading these a bit later. Thank you so much! (^ ^ * )

LizFoster (118)

@Highwayman These actually seem pretty up my alley, ha ha ha

Highwayman (961)

@LizFoster awesome! Perfect I’m so happy they actually are helping someone lol. I haven’t picked them up in a while

LizFoster (118)

@Highwayman Yeah! Math is really fun if you can find some thing or things that you find fascinating (for me it was π, Σ, and complex numbers), and from there, you can find that things that seemed really difficult or complex, just needed a bit more context/clarification.

Highwayman (961)

@LizFoster ehh idk.... I really like cryptography for example but I don’t even know where to start with the math. I just hit a series of strange unintelligible symbols and math jargon and then have no idea what to do.

LizFoster (118)

@Highwayman Oh, cryptography looks fun. I'd suggest looking on YouTube; half of the stuff I've learned came from Numberphile, 3Blue1Brown, and Mathologer, so I'm sure that there are loads of tutorials and such for cryptography! Here are a few I found if you have the time for it:

https://www.youtube.com/watch?v=cqgtdkURzTE
https://www.youtube.com/channel/UC1usFRN4LCMcfIV7UjHNuQg

and then for fun (probably not as related Lol):

https://www.youtube.com/watch?v=TvsiLV7RLx4

Highwayman (961)

@LizFoster thank you! I definitely will cryptography is super fun lol :P I’m pretty sure I heard somewhere that @enigma_dev is a cryptography nerd too I think...?

LizFoster (118)

@Highwayman Oh, it says it in his account biography, so maybe he is! (Lol) Glad I could help ^ ^*

Highwayman (961)

@LizFoster yeah there we go I knew it lol XD

Highwayman (961)

@LizFoster

If P and Q are two points on an elliptic curve such that kP = Q, where k is a scalar and sufficiently large, it is computationally infeasible to obtain k if k is the discrete logarithm of Q to the base P . Note that this is computationally infeasible even if P and Q are known.

XS ohh boy. Here we go again lol.

LizFoster (118)

@Highwayman Hahahaha don't worry about things that word it like that (I never do). See if you can find a simpler explanation elsewhere

Highwayman (961)

@LizFoster ok. :) I was actually just going to try and look it up, but that actually sounds like a better idea lol

LizFoster (118)

@Highwayman Yeah, whenever I don't understand something, I look up an article or video on that topic. It really helps!

enigma_dev (7038)

I was summoned! Yeah, I’m a big cryptography fan! feel free to pimg me with q‘s! @LizFoster @Highwayman

Highwayman (961)

@enigma_dev Oh, yay! Hi! Um, so
I was reading some stuff on the diffie-hellman key exchange, and they started discussing ECC, which I though was basically just another asymmetric encryption algorithm like RSA, but now I’m kinda confused because it started to look like it was just another form of the aforementioned diffie-hellman exchange, so I guess what my question is is what is elliptic curve cryptography?

LiamDonohue (167)

the only cryptography i know is the Caesar shift wheel lol @LizFoster

Highwayman (961)

@LiamDonohue hmmm I thought I just saw you talking about SHA256 a little bit ago..? Or maybe that was someone else? Gah I’m going insane I can’t remember shit anymore :(

LiamDonohue (167)

no idea what your talking about lol @Highwayman

LizFoster (118)

@Highwayman dang, turned down T~T huh

LizFoster (118)

@Highwayman Don't worry, I'm sure he didn't mean anything by it! (Lol)

Highwayman (961)

@LizFoster yeah, I’d think that. I sometimes accidentally have ppl slip through the cracks so I don’t really blame him.