vector.go

package main

import (
	"math"
)

// A 2d Vector
type Vector struct {
	X, Y float64
}

func (v1 Vector) Equals(v2 Vector) bool {
	return (v1.X == v2.X) && (v1.Y == v2.Y)
}

// Vector equals function that accounts for floating point noise
func (v1 Vector) NearlyEquals(v2 Vector, epsilon float64) bool {
	return math.Abs(v1.X-v2.X) < epsilon && math.Abs(v1.Y-v2.Y) < epsilon
}

// All the following mathematical functions can be used as the following:
// v1 = Vector{1,2}
// v2 = Vector{3,4}
//
// sum = v1.Add(v2)

func (v1 Vector) Add(v2 Vector) Vector {
	return Vector{v1.X + v2.X, v1.Y + v2.Y}
}

func (v1 Vector) Subtract(v2 Vector) Vector {
	return Vector{v1.X - v2.X, v1.Y - v2.Y}
}

func (v Vector) Scale(scalar float64) Vector {
	return Vector{v.X * scalar, v.Y * scalar}
}

func (v Vector) Magnitude() float64 {
	return math.Sqrt(v.X*v.X + v.Y*v.Y)
}

func (v Vector) Normalize() Vector {
	mag := v.Magnitude()
	return Vector{v.X / mag, v.Y / mag}
}