// vector provides a Vec type and methods for performing vector arithmetic
package vector

// 3 dimensional vector
type Vec struct {
  X, Y, Z  float64
}

// Cross returns the cross product between vectors v and o
func (v Vec) Cross(o Vec) Vec {
  return Vec{v.Y*o.Z - v.Z*o.Y, v.Z*o.X - v.X*o.Z, v.X*o.Y - v.Y*o.X}
}

// Doc returns the dot product between vectors v and o
func (v Vec) Dot(o Vec) float64 {
  return v.X*o.X + v.Y*o.Y + v.Z*o.Z
}

// sub subtracts o from v
func (v Vec) Sub(o Vec) Vec {
  return Vec{v.X - o.X, v.Y - o.Y, v.Z - o.Z}
}