// D3Vector.java
// ３次元 ベクトル クラス
// Copyright (C) 1996, 1997 Y.Nagatani
// nagatani@eken.phys.nagoya-u.ac.jp

public class D3Vector {
	public double	x,	y,	z;
	D3Vector () {
		
		set (0,0,0);
	}
	D3Vector (double x, double y, double z) {
		
		set (x, y, z);
	}
	public D3Vector set (double x, double y, double z) {
		
		this.x = x;
		this.y = y;
		this.z = z;
		return	this;
	}
	public D3Vector translate (D3Vector vect) {
		
		return	add (vect);
	}
	public D3Vector add (D3Vector vect) {
		
		this.x += vect.x;
		this.y += vect.y;
		this.z += vect.z;
		return	this;
	}
	public D3Vector scalar (double s) {
		
		this.x *= s;
		this.y *= s;
		this.z *= s;
		return	this;
	}
	private D3Vector rotate (double arg, double v[]) {
		
		double	sin = Math.sin (arg),
			cos = Math.cos (arg);
		double	A = v[0],
			B = v[1];
		v[0] =   cos * A + sin * B;
		v[1] = - sin * A + cos * B;
		return	this;
	}
	public D3Vector rotXY (double arg) {
		
		double	sin = Math.sin (arg),
			cos = Math.cos (arg);
		double	A = x,
			B = y;
		x =   cos * A + sin * B;
		y = - sin * A + cos * B;
		return	this;
	}
	public D3Vector rotYZ (double arg) {
		double	v[] = {y, z};
		rotate (arg, v);
		y = v[0];
		z = v[1];
		return	this;
	}
	public D3Vector rotZX (double arg) {
		double	v[] = {z, x};
		rotate (arg, v);
		z = v[0];
		x = v[1];
		return	this;
	}
}