Vector Angle Calculation in JavaScript

Introduction

In this lab, we will explore the concept of vector angle and learn how to calculate the angle between two vectors using JavaScript. We will use various mathematical functions such as Math.pow(), Math.sqrt(), and Math.acos() to perform the necessary calculations and derive the desired result. Through this lab, we will gain a better understanding of vector operations and their practical applications.

Vector Angle Calculation

To calculate the angle (theta) between two vectors, follow these steps:

1. Open the Terminal/SSH and type node to start practicing coding.
2. Use Array.prototype.reduce(), Math.pow() and Math.sqrt() to calculate the magnitude of each vector and the scalar product of the two vectors.
3. Use Math.acos() to calculate the arccosine and get the theta value.

Here's an example code snippet:

const vectorAngle = (x, y) => {
  let mX = Math.sqrt(x.reduce((acc, n) => acc + Math.pow(n, 2), 0));
  let mY = Math.sqrt(y.reduce((acc, n) => acc + Math.pow(n, 2), 0));
  return Math.acos(x.reduce((acc, n, i) => acc + n * y[i], 0) / (mX * mY));
};

vectorAngle([3, 4], [4, 3]); // 0.283794109208328

This function takes two arrays (x and y) as arguments and returns the angle (in radians) between them.

Summary

Congratulations! You have completed the Vector Angle lab. You can practice more labs in LabEx to improve your skills.