Name: 1.2 Vector Math - The Nature of Code
Uploaded: 2020-03-27T19:15:28.000Z
Duration: 11 min 57 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

Welcome back to the second video in Chapter 1

So I could go in a number of different directions here.

what direction I'm going to go in right now.

But ostensibly, if you're following "The Nature of Code"

book along with these videos, the next topic

What are the kinds of operations that you

might be used to doing with scalar quantities?

Multiply, divide, square root, power of three,

all of these kinds of mathematical operations,

those mathematical operations exist for vectors as well.

And a lot of times it's as simple as a vector addition

And that's really where I'm going to start.

rather than go through a laundry list, which

is how the book does this to a bit more extent, of vector math

one at a time, I'm going to take the next step

in the random walker example and discover what kinds of vector

to talk about the different functions, vector math

And one of the reasons to use the P5 vector class beyond just

of these common operations exist as functions in the P5 vector

class itself, like add, subtract, multiply,

dot product, cross product, distance, normalized limit,

So I expect that over the course of many, many videos

throughout this whole series, I will get to a lot of these.

But you also might just take a moment to pause

and click through and look at some of these yourself.

I am taking the x component of the position vector, the y

So let's start by discussing vector addition.

We'll call them u and v. Actually, you know what?

That's a very-- the u and v, the way I write u and v,

Vector a and vector b-- and vector notation

often uses the arrow on top of the letter

And let's say the vector b is, I don't know, 2, negative 1.

So this is actually a really simple operation to do,

actually just involves adding the components together.

So this would be 5, 3, because 3 plus 2 is 5

and 4 plus negative 1, or 4 minus 1, is 3.

just say that a minus b, vector subtraction,

is also what you probably imagine it would be,

the x component minus the exponent, the y component

And this would extend into any dimensional space.

If my vector had 10 numbers in it, it would be the same thing.

So these are how these operations actually work.

However, while this is so incredibly simple,

to actually look at how this appears in a diagram,

because this really relates to how we're using

Let's think about our two-dimensional Cartesian

space, the one where y points up and x points to the right.

So not the upside down one, what with the demi-gorgon in it.

And so the vector 3, 4 would be 1, 2, 3--

Adding vectors, the resulting vector c, which is a plus b,

is the vector that results from putting these two end to end.

So it doesn't matter which one I do first.

Subtitles ListPlay Video

1.2 Vector Math - The Nature of Code

ultimately

sort

equivalent

figure