Coding Challenge
ฝัง
- เผยแพร่เมื่อ 27 พ.ค. 2024
- 🥧 Happy Pi Day 2020! In this challenge, I build a simple web application using p5.js and node.js to search in the first billion digits of Pi. Code: thecodingtrain.com/challenges...
🕹️ p5.js Web Editor Sketch: editor.p5js.org/codingtrain/s...
🎥 Previous video: • Coding Challenge #155:...
🎥 Next video: • Coding Challenge #157:...
🎥 All videos: • Coding Challenges
References:
🔗 Pi Searcher: angio.net/pi/
🔗 Peek in Pi: pi.fathom.info/
🔗 Boyer-Moore String Search: en.wikipedia.org/wiki/Boyer%E...
🔗 createReadStream(): nodejs.org/api/fs.html#fscrea...
Videos:
🎥 ES6 Arrow Function: • 16.3: ES6 Arrow Functi...
🎥 Server-side with Node.js: • 2.1 Server-side with N...
🎥 Working with Data and APIs track: • Working with Data and ...
🔴 Coding Train Live 189: • Coding Train Live 189:...
Related Coding Challenges:
🚂 #140 Leibniz Formula for Pi: • Coding Challenge #140:...
🚂 #161 Estimating π from Random Numbers with Euclid's Algorithm: • Coding Challenge 161: ...
🚂 #169 Pi in the Sky Game: • Coding Challenge 169: ...
Timestamps:
0:00 Introduction
2:30 Importing Pi Into p5.js
3:37 Searching Numbers in Pi
7:09 IndexOf Function
13:13 Importing 1GB File
16:38 Dividing the Data into Read Streams
18:25 Searching 1 Billion Digits
19:44 Creating an API
28:42 Conclusions and Ideas
Editing by Mathieu Blanchette
Animations by Jason Heglund
Music from Epidemic Sound
🚂 Website: thecodingtrain.com/
👾 Share Your Creation! thecodingtrain.com/guides/pas...
🚩 Suggest Topics: github.com/CodingTrain/Sugges...
💡 GitHub: github.com/CodingTrain
💬 Discord: thecodingtrain.com/discord
💖 Membership: th-cam.com/users/thecodingtrainjoin
🛒 Store: standard.tv/codingtrain
🖋️ Twitter: / thecodingtrain
📸 Instagram: / the.coding.train
🎥 Coding Challenges: • Coding Challenges
🎥 Intro to Programming: • Start learning here!
🔗 p5.js: p5js.org
🔗 p5.js Web Editor: editor.p5js.org/
🔗 Processing: processing.org
📄 Code of Conduct: github.com/CodingTrain/Code-o...
This description was auto-generated. If you see a problem, please open an issue: github.com/CodingTrain/thecod...
#math #piday #nodejs #p5js #javascript
0:40 "A ressource where you can download all the digits of Pi."
Wait, ALL of them? That's a very impressive website.
The technology is finally here!
pi has infinitely many digits no database ever could hold all digits of pi
@@MohamedSaad-zy7pu woosh
I can give you all the digits of pi right here in this comment: 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9. Just rearrange and repeat some of them as you see fit to recreate pi. You are welcome. :-)
@@xnick_uy XD
Hey. I am just a random 30 yo Brazilian geologist switching carreers and I want to say that today is saturday night, world has corona, I am anxious, alone, thinking about life but this video and your work/passion/humour make things easier for me and I am sure for a lot of other people. Keep up the good work. We appreciate it.
Boa Cara, muita gente de programação é de outras áreas.
Who noticed Dan replaced so many times "million" by "billion", by deleting "million" and writing "billion" instead (or vice versa), while there is just one letter to change?
🤦♂️
28:18 Shocking news! Man found last ten digits of PI
We can use the tail command in bash to find the last ten digits of pi like so:
tail -c 10 pi-billion.txt
"last ten digits of KNOWN PI sequence"
@@kimeg7294 Oh... Oh no, sweet child... A billion is just the first sneeze of what has been calculated.
Bigger shock - they turned out to be . . . 9876543210.
Fred
No way Dan... ALMOST 1 MILLION SUBSCRIBERS NOW!? I remember your classic P5 tutorials before the whole coding train thing even existed!! I just wanna say, I'm proud, man.
Thank you!
I am always a bit amazed at how incredibly much larger a billion is than a million. I know the math is super simple, but the intuition of it is really difficult for me to grasp
Morten Flecks if you look at a millimetre on a metre stick, same ratio
Look back a dozen decades when the definition of billion was a million million in England, and you will be more amazed.
That's why people don't realize how being a billionaire is completely unnecessary and actually detrimental to society.
See it like this: if your salary was 1 million $ per month (not per year, per month), it would take 84 years (aka more than an entire working lifetime) to earn a billion $. And that would be without spending a single $ or paying any tax during all that time.
@@shreerangvaidya9264 no, it's a thousand million. A million million is a trillion.
Do everyone will ignore the fact that , coding train will soon hit 1 million subscribers. I didn't even how when you reached too close to 1M. It had been 3-4 years now since i am watching your videos.... You taught me processing, you taught me the Nature Of code.... This channel is absolute gold.... I don't remember whats the first video i watched but i could proudly say that i had watched almost every of them. 😍 love from india Dan❤
shashank Sahu he has hit 1 million as of today!
Pi was calculated to 50Trillion digits, a text file is available but it's 40TB! Today it's also been added to the pi.delivery api
What is the use of this
@@bilallaaroussi7110 Esoteric.
It's of some interest to mathematicians to know whether there are any non-random patterns in the digits of π, and these mammoth collections of digits can be used to answer such statistical questions.
Fred
50 trillion digits in 40 trillion bytes? Must be slightly compressed, no? (Even if that's the binary terabyte = 2⁴⁰ B, 40 TB ≈ 44.0 trillion bytes.)
Fred
50T
40TB
Wot
Use it for some good random numbers
Finally another Coding Challenge! I really hope for more coding challenges, I really like these videos!
Congrats on 1 millions subs! Love these challenges! I wish you a lot of luck in the future of your channel
Ah!!! You are so close to 1 million subs!! Congrats Dan! You’ll always be the guy that made programming click for me :)
Ayyyye our first coding challenge in a while! And a good one at that!
0:00 Why, happy Pi day to you too!
You are the best. Your energy is incredible, the world needs more like you. My wife asks what is that song you are singing? lol a man in his 50s singing coding train. THANKS!!!
This is my first video. I love this guy already. He makes learning coding fun. 😊
Nice! I saw this suggestion on the github and was hoping you'd do it.
The fact that the first million digitals is 1mb and the first billion is 1gb gives me great satisfaction.
That buzz sound effect kept jump scaring me!
jup the buzzer is just wrong. short conductor whistle or passing train will be much more fitting ;)
BCD encoding the file would be 500Meg for a 1 billion digits file, not sure how much you'd get from gz or zip since pi is a high entropy number.
this man can visualize anything
waiting for this on pi day!!!!!
Love it!
This requires at last 1gb or RAM! Yiou should search directly from the stream, searching in chunk by chunk
Good point!!!
I love this!
Cool idea!
I have plenty enough file storage on my local server for 1 trillion digits (43.7GB), I may be able to set it up as a coding challenge by dumping the variables as I run out of ram and searching chunks of the file, but it would be quite a slow process.
But shouldnt it be 1TB
thats insane compression
Try to use KMP algorithm and look for matchs while you read the stream
Why You Dont try make a random face ganerator in processing(or you cant do that?)
I promise you that I was waiting this video from 1 year ago
KMP is best algorithm for me.
Great video, youre a very engaging teacher, would you consider doing some videos on functional programming, preferably Haskell, I have trouble understanding it and there hardly any good tutorials on TH-cam
It would be really neat to have the node server lazily evaluate pi as you search, until it finds the string of digits, no matter how long it takes.
the video title should be *Writing Built in Javascript Function* 😂😂
Thanks for this great video
Peek in pi => pecan pie, just so it's easier to remember
If you substituted music notes for numbers, what would Pi sounds like? You could also see if you could find certain melodies within Pi.
Edit: I commented this before watching till the end of the video haha.
Can we get some more coding challenges? Maybe 3D tic-tac-toe or adding physics to your fractal trees from ages ago?
What about actually calculating the first thousand or million or so digits of pi?
You know things get handy when it comes to a 1GB file of plain text
You should calculate pi in the code so you can just set a number for the number of digits you want
I came here for Pie... but all he was talking about was PI.
How about searching for the digit of a certain digit in pi? Could be an interesting recursive function
You could speed it up by a factor of 4 by instead of search for chars, search for longs (that is 4 chars at once). Caveat is that your search string should be at least 4 chars ...
Even faster would be keeping track of where all digits are, that would speed it up by factor of ten, but you would use 10 times more memory.
Performance tuning is always a trade-off for something else 😬
Thanks for these suggestions!
The computer would still have to compare the sane number of bits, so it isn’t really a 4x speed up
See it like this: compare 12 bytes or compare 3 longs.
The amount of bits is the same but the CPU can do it in less instructions, thus faster.
10:04 If the condition ends up being true, you can just return -1 instead of keeping track of a variable "found"
You can't do so, you need to exhaustively search the entire string. Say you're looking for 1419, U would go 1 4 1, then 5, but you cannot exit there.
I love pi day challange😍
Close to 1 million subscribers ♥️♥️
Hi can make programe which can read the chart provided by a website on the screen and create signals on activity detected !?
what if i +j will exceed the length of the text file , when the value of i is at last , or somewhere in the last
27:56 We can use the tail command in bash to cat the last ten digits like so:
tail -c 10 pi-billion.txt
Brent Trenholme i thought it may give an exception something like out of bounds.
Brent Trenholme yeah 😄, thnx
indeed, i should have accounted for this!
The Coding Train i need coding train sticker for my laptop if i may ask. 🥺 Fan from India
Well, here In Spain we write the date in different order, so it is 14/3/20. Which is pretty sad 😞😞
Qwerty GMR Same in Europe
@@leo848 Spain is in Europe
@@HiHi-ur3on oh yeah.. i forgot it just moved
@@HiHi-ur3on yeah.. after all, you should eat your cereal
Cosmin Cosmin I meant holy Europe
hey dan! i am trying to implement this to my express server which holds projects, but it seems like the app.use overrides the front page (which is "/"). can anyone help me?
Is there a pi inside pi
find 3
then 31
then 314
then 3141
I wonder what that sequence would look like ?
Bailey-Borwein-Plouffe formula
is there a Prossesing Server ?
All your videos are so great and so entertaining. Oh and:
function askQuestion(question, sender) {
if ( typeof question !== "string" && typeof sender !== "string" ) {
return "The question and sender is not a proper one";
}
if (question == "Any ideas for another video?" && sender == "David Shiffman") {
return {
getTheIdea: function() {
console.log("Put the code to run this console.log as a reply");
}
dumpIdea: function() {
try {
this.getTheIdea = null;
} catch (e) {
console.error("getTheIdea Cannot be deleted");
}
}
}
}
return "Sorry, No answer here...";
}
Sir, I like how you deliver content about machine learning. I really want good people like you to contribute in the fight against corona virus. I have an idea, what if you create content about the neural network chatbot. I think this is useful for socialization about corona virus to the public. Some doctors say, prevention is the best medicine for all diseases. The socialization of preventing corona virus at this time is the most needed thing to suppress the virus spread.
Thanks, i hope you at least read this.
No need for a bigger file. The natural challenge here is to compute the digits themselves. But I guess it requires a bit of mathematics.
Code simplification:
let start = search.charAt(0);
for (let i = 0; i < txt.length; i++) {
if (txt.charAt(i) === start) {
let found = true;
for (let j = 1; j < search.length; j++) {
if (txt.charAt(i + j)) !== search.charAt(j) {
found = false;
break;
}
}
if (found) {
return i;
}
}
}
return -1;
is the same as
for (let i = 0; i < txt.length; i++) {
if (txt.charAt(i) === search.charAt(0)) {
let found = true;
for (let j = 1; j < search.length; j++) {
if (txt.charAt(i + j)) !== search.charAt(j) {
found = false;
break;
}
}
if (found) {
return i;
}
}
}
return -1;
is the same as
for (let i = 0; i < txt.length; i++) {
let found = true;
for (let j = 0; j < search.length; j++) {
if (txt.charAt(i + j)) !== search.charAt(j) {
found = false;
break;
}
}
if (found) {
return i;
}
}
return -1;
Do you know any other code languages other than java script? I learned the bare minimum of java script and now I’m learning html to create a website for my friend
What program is he using?
After 1 billion you would need to use algorithms similar to sorting algorithms.
You must do Tau Day too
Happy Pi day!
wasn't pi supposed to be a non-repeating and non-terminating decimal number? there are repeating numbers in this video though (such as ....99999....)?
Or, in two minutes but with no error checking but including time to download file:
import sys
target = sys.argv[1]
data = open('onemeg.dat').read()
pos = data.find(target)
if pos < 0:
print '{} not found'.format(target)
else:
print '{}: {} {}'.format(pos, target, data[pos+len(target):pos+41])
Make a Picross solver.
double value=sqrt(2.0);
println(value); // prints many decimal places.
text(value, 100,100); gets an error.
He even included inside in the title
Happy 🥧 day🤓
Why number 3 is not in?
1 mill!!
I forgot it was pi day...
SHAME ON ME
you are pi pi poo poo
@@levinsondsouza pie pie?
Oh, do you have a new character?
Happy Gilfoyle
You could implement kmp algorithm, this algorithm is not so hard to implement...
Damm i even still haven't moved on since the last pi day special
This certainly has been an interesting year so far...
You are supposed to use pattern matching for this problem, and not for loops..
you are supposed to shut up
Im gonna make this in python
Isn't it as easy as pressing ctrl+f inside a pi.txt file?
But 1 million digits of Pi file should weight only about 2 megs - in 2020 it is nothing even for JS. It is very small amount of memory.
And, well, 1 billion is about 2 gigs, depends on encoding.
When is 1 trillion coming haha
Make plastic deformation simulation
NINE
NINE
NINE
NINE
NINE
NINE
9:40 is he writing on the wall with a sharpie??
don't worry it's a dry erase whiteboard
15:07 it's not binary, it's hexadecimal I know that because I do Unicode stuff every now and then
They're interchangeable in this context. It is just outputted as hexadecimal, it is technically a binary, usually buffers are binary data. What does unicode have to do with this anyway?
what the hell dude, why you gotta do me like that?
At 0:59 your buzzer sounds exactly like my door bell and i went outside to check if anybody just rang...
*EDIT:* and he keeps using that buzzing sound throughout the video....
Ooops, sorry about that!
Is it maybe fun, to find self indexing numbers in the first billion numbers of Pi? So like 3.1415(edit) 1 would be index 1 and thus be its own index. Or maybe if 1 would index 0.
I got the idea from this Numberphile video about looping numbers in Pi( starting with a given number, finding its index, than looking at that numbers it index and so on)
Here is the video th-cam.com/video/W20aT14t8Pw/w-d-xo.html
i was in chat during the stream :))
Here is the code for Processing(Java):
String raw[];
String digits;
String surch = "";
void preload() {
raw = loadStrings("pi.txt");
}
void setup() {
size(500, 500);
preload();
digits = raw[0];
}
void draw() {
background(0);
suchBox();
int index = digits.indexOf(surch);
fill(0, 100, 255);
text(index - 1, width/2, height/1.5);
}
void keyPressed() {
if (keyCode == BACKSPACE) {
surch = "";
} else {
surch += key;
}
}
void suchBox() {
rectMode(CENTER);
textAlign(CENTER, CENTER);
fill(255);
stroke(0);
rect(width/2, height/2, width/2, height/8);
fill(0);
textSize(20);
text(surch, width/2, height/2);
}
dude literally i had this idea like a week ago to publish it today (pieandme.com)
Peeing inside Pik -_-
Pi day should be 14% through the month of March, not the 14th day of March.
Great video, but this annoing sound when you correct yourself...
Game made with p5.js: spaceadvent.glitch.me/
10:00 txt.charAt(int) at line 17 could overflow.....
Do 1 trillion
grep
This is O(N²)
It's actually pretty close to theta(n), since the length of the sequence to be searched is small relative to s billion digits
I think the big o is still O(N)
It would be O(N^2) when your search string would be always as big as the digits of PI
Suggestion for the editor: have music playing in the background and increase the volume of the music when showing a fast forwarded lapse of Dan working through code, rather than having the music cut in and out
7th
Whoever read this, you'll be successful one day. Let's do this for the future
Pi = 22➗7