main/src/georegression/struct/point/Vector3D_F64.java
public void minus( Point3D_F64 a , Point3D_F64 b ) {
		x = a.x - b.x;
		y = a.y - b.y;
		z = a.z - b.z;
	}
public void minus( Point3D_F64 a , Point3D_F64 b ) {
		x = a.x - b.x;
		y = a.y - b.y;
		z = a.z - b.z;
	}
In-place minus operation. this = a - b.

@param a Point
@param b Point