Coding Challenge #139: Calculating Digits of Pi with Collisions

References:

Videos:

Related Coding Challenges:

Timestamps:
0:00 Introduction!
1:51 Basic code of the structure
7:00 Simulating elastic collision between two blocks
12:03 Simulating the wall
13:59 Adding the clack!
14:29 Counting the collisions!
18:09 Adding timesteps to control approximation
24:12 Adding constraints to speed up animation
26:47 Watching collisions upto 11 digits of pi!
28:46 Other methods to simulate elastic collisions and things to try!
30:50 Fake outro (and a special Pi Day song!)

Editing by Mathieu Blanchette
Animations by Jason Heglund
Music from Epidemic Sound

#3blue1brown #elasticcollision #piday #eulermethod #p5js #javascript

[guitoo]

This method is not time sensitive. Because of conservation of momentum and energy, Euler integration is not an issue.
The problem is that when a collision happens, you let the 2 objects intersect with themselves and the wall. This leads to the small cube slowly drifting through the wall.

If you just snap back the cubes positions after a collision, you should be fine.

Technically the pieces don't even need to move, you just have to count the collisions respecting the alternating order of wall and cube collisions.

[justinhoffmann]

I love that the video length is Pi (31:41)! Happy #PiDay!

[gordonchan]

15:30 FUNDAMENTAL THEOREM OF ENGINEERING

[sidalisaadi]

Calculates Pi On Pi day ... with a Pi long video ...
how committed someone can be?

[mebamme]

27:14
It goes like this, the wall, the block,
the drawing loop, the ticking clock,
the baffled Dan programming Pi collisions 🎶

[mebamme]

It's amazing how accurate you got it!

Even having seen the 3blue1brown video, I was blown away by how the digits of Pi appeared, and the correct ones to boot! And all with so little code.

[rageace]

engineers: "that's kinda like pi, 3!"

[alliseth]

the video length is 31:41 this is just excessive

[sangeetamankani]

Man For this you deserve 3, 141, 592, 653, 589, 793, 238, 462, 643, 383, 279, 502, 884, 197, 169, 399, 375, 105, 820, 974, 944, 592, 307, 816, 406, 286, 208, 998, 628, 034, 825, 342, 117, 067 subscribers.


And No I didn't copy-paste or see and type it. I remember 100 digits of PI using ASAP Science's song '100 digits of PI '!!

[WildAnimalChannel]

Knowing the velocity of both blocks, you could calculate the point in space and time where they collide. So you don't need time steps at all! (Except for animation purposes). If the time until collision is above say 1/60th of a second you could use a time step for animating. In fact that would give you a nice iterative formula for pi. (That would converge quite slowly!)

[sirnicoosokhan]

You could also use this way:
console. log(Math.PI);

[nitinrangarajan]

This is frickin amazing :D Math and Computer Science are just so amazing! Happy Pi Day everyone

[technodruid]

Man, it's really cool you just see the physics through the math, like with hypothesising what the m=1 scenerio is. You're quite the polymath!

[followthetrawler]

That clack sound is the same as the clack that Clackers made, a toy from the late 60's that used to break kids wrists :) Good article on Wikipedia about them.


Super video!

[ItsDrike]

26:52 I love the song, you should upload a video just with the song

[avi]

29:47 The difference between float/double and BigDecimal, as well as the difference between int/long and BigInteger, is that using primitive types, the JVM is allocating a chunk of memory just for that primitive type's previously-set boundary, while as a for BigInteger/BigDecimal, the JVM is directly using the memory to store the bytes, which naturally results in a bigger usage of memory for the application.
If you have a lot of RAM and you need high-precision for numbers, you can safely use BigInteger/BigDecimal. Just be careful not running into Infinite loops!

[Xnoob]

12:27
We can think of the wall as 256 high bedrock

[justkeerat]

I did this in processing myself and after 7 digits it was just too slow.. I can't believe it went till 9 digits at such a good speed. But it's super impressive. I love how we all enjoy coding mathematical ideas that just make programming fun😂❤️

[JCDreaming]

What an amazing video as always! The video edition is every time getting better too. Great work!!! Thanks!!!

[ahmedelselly]

man i was feeling depression because i field to learn advanced javascript and u made me more interested in it u made me change my mind