You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
100 lines
2.0 KiB
Java
100 lines
2.0 KiB
Java
public class Vector2d {
|
|
double x, y;
|
|
|
|
public Vector2d(double x, double y) {
|
|
this.x = x;
|
|
this.y = y;
|
|
}
|
|
|
|
public Vector2d conj() {
|
|
return new Vector2d(x, -y);
|
|
}
|
|
|
|
public Vector2d sub(Vector2d b) {
|
|
return new Vector2d(x - b.x, y - b.y);
|
|
}
|
|
|
|
public Vector2d add(Vector2d b) {
|
|
return new Vector2d(x + b.x, y + b.y);
|
|
}
|
|
|
|
public Vector2d mul(Vector2d b) {
|
|
return new Vector2d(x * b.x - y * b.y, x * b.y + y * b.x);
|
|
}
|
|
|
|
public Vector2d div(Vector2d b) {
|
|
return this.mul(b.conj()).mul(1 / b.len2());
|
|
}
|
|
|
|
public Vector2d mul(double b) {
|
|
return new Vector2d(x * b, y * b);
|
|
}
|
|
|
|
double len2() {
|
|
return x * x + y * y;
|
|
}
|
|
|
|
double len() {
|
|
return Math.sqrt(x * x + y * y);
|
|
}
|
|
|
|
public Vector2d norm() {
|
|
return len() == 0 ? new Vector2d(0, 0) : mul(1 / len());
|
|
}
|
|
|
|
public double cross(Vector2d b) {
|
|
return x * b.y - y * b.x;
|
|
}
|
|
|
|
public double dot(Vector2d b) {
|
|
return x * b.x + y * b.y;
|
|
}
|
|
|
|
public Vector2d rot() {
|
|
return new Vector2d(-y, x);
|
|
}
|
|
|
|
public double proj(Vector2d p) {
|
|
return dot(p) / len();
|
|
}
|
|
|
|
public static Vector2d polar(double r, double theta) {
|
|
return new Vector2d(r * Math.cos(theta), r * Math.sin(theta));
|
|
}
|
|
|
|
public static Vector2d exp(Vector2d a) {
|
|
return polar(Math.exp(a.x), a.y);
|
|
}
|
|
|
|
public Vector2d rotate(Vector2d p, double angle) {
|
|
return p.sub(this).mul(exp(new Vector2d(0, angle))).add(this);
|
|
}
|
|
|
|
Vector2d rotate2(Vector2d p, double angle) {
|
|
p = p.sub(this);
|
|
double cs = Math.cos(angle);
|
|
double sn = Math.sin(angle);
|
|
return new Vector2d(p.x * cs - p.y * sn, p.x * sn + p.y * cs).add(this);
|
|
}
|
|
|
|
public Vector2d reflect(Vector2d p, Vector2d q) {
|
|
Vector2d s = q.sub(p);
|
|
return this.sub(p).div(s).conj().mul(s).add(p);
|
|
}
|
|
|
|
@Override
|
|
public String toString() {
|
|
return "Vector2d [x=" + x + ", y=" + y + "]";
|
|
}
|
|
|
|
// Usage example
|
|
public static void main(String[] args) {
|
|
Vector2d u = new Vector2d(0, 0);
|
|
Vector2d v = new Vector2d(1, 0);
|
|
Vector2d a = u.rotate(v, Math.PI * 1.0);
|
|
Vector2d b = v.rot().rot();
|
|
System.out.println(a);
|
|
System.out.println(b);
|
|
}
|
|
}
|