A tiny TypeScript library for 2D vector math.
npm install vecti
A tiny TypeScript library for 2D vector math.
- 🧮 Addition, subtraction, multiplication and division
- ✨ Dot, cross and Hadamard product
- 📏 Length and normalization
- 📐 Rotation by radians and degrees
- 🪨 Immutable data structure encourages chaining
- 💾 Tiny and typed
- d3-graph-controller - Calculation of graph edge paths
``bashyarn
$ yarn add vecti
Usage
Vectors have two properties,
x and y, representing their components.
Since vectors are entirely immutable, they are read-only.To use Vecti, add the following import to your TypeScript file.
Instances of the
Vector class can be created either by using its constructor or the static method of the class.
The latter accepts a number array of length 2, with the first element being the x-axis component and the second element being the y-axis component.`ts
import { Vector } from 'vecti'// eslint-disable-next-line no-new
new Vector(42, 7) // == Vector { x: 42, y: 7 }
Vector.of([42, 7]) // == Vector { x: 42, y: 7 }
`$3
Two vectors can be added using the
add method.`ts
const a = new Vector(0, 1)
const b = new Vector(1, 0)a.add(b) // == Vector { x: 1, y: 1 }
`$3
Two vectors can be subtracted using the
subtract method.
The parameter is the subtrahend and the instance is the minuend.`ts
const a = new Vector(2, 1)
const b = new Vector(1, 0)a.subtract(b) // == Vector { x: 1, y: 0 }
`$3
Vectors can be multiplied by scalars using the
multiply method.`ts
const a = new Vector(1, 0)a.multiply(2) // == Vector { x: 2, y: 0 }
`$3
Vectors can be divided by scalars using the
divide method.
The parameter is the divisor and the instance is the dividend.`ts
const a = new Vector(4, 2)a.divide(2) // == Vector { x: 2, y: 1 }
`$3
The dot product of two vectors can be calculated using the
dot method.`ts
const a = new Vector(2, 3)
const b = new Vector(1, 3)a.dot(b) // == 11
`$3
The cross product of two vectors can be calculated using the
cross method.
The cross product of two vectors a and b is defined as a.x b.y - a.y b.x.`ts
const a = new Vector(2, 1)
const b = new Vector(1, 3)a.cross(b) // == 5
`$3
The Hadamard product of two vectors can be calculated using the
hadamard method.`ts
const a = new Vector(2, 1)
const b = new Vector(1, 3)a.hadamard(b) // == Vector { x: 2, y: 3 }
`$3
The length of a vector can be calculated using the
length method.Length is defined as the L2 norm.
`ts
const a = new Vector(1, 0)a.length() // == 1
const b = new Vector(-3, 4)
b.length() // == 5
`$3
A normalized version of a vector can be calculated using the
normalize method.
The resulting vector will have a length of 1.`ts
const a = new Vector(2, 0)a.length() // == 2
const b = a.normalize() // == Vector { x: 1, y: 0 }
b.length() // == 1
`$3
Vectors can be rotated by radians or degrees using the methods
rotateByRadians and rotateByDegrees respectively.Due to the rotation using
Math.sin and Math.cos, rounding errors can occur.
Notice that in the example below, the resulting x-component is 6.123233995736766e-17 and not 0 as expected.`ts
const a = new Vector(1, 0)a.rotateByDegrees(90) // == Vector { x: 6.123233995736766e-17, y: 1 }
a.rotateByRadians(Math.PI / 2) // == Vector { x: 6.123233995736766e-17, y: 1 }
`$3
Vecti encourages chaining methods to achieve readable and concise calculations.
`ts
import { Vector } from 'vecti'new Vector(-5, 0)
.normalize()
.rotateByDegrees(180)
.add(Vector.of([0, 1]))
.multiply(42) // == Vector { x: 42, y: 41.99999999999999 }
`Development
`bash
install dependencies
$ pnpm installbuild for production
$ pnpm buildlint project files
$ pnpm lintrun tests
$ pnpm test
``MIT - Copyright © Jan Müller