Vector2D

vector_2d.rb

class Vector2D
  include Math
  attr_accessor :x, :y
  def self.magnitude_angle magnitude, angle
    x = magnitude * cos(angle*PI/180)
    y = magnitude * sin(angle*PI/180)
    new x, y
  end
  def initialize x, y
    @x = x; @y = y
  end
  def magnitude
    sqrt x*x + y*y
  end
  def angle
    rad = atan y/x
    rad += PI if x < 0
    rad += 2*PI if rad < 0
    rad*180/PI
  end
  def + other
    self.class.new x+other.x, y+other.y
  end
  def - other
    self.class.new x-other.x, y-other.y
  end
  def -@
    self.class.new -x, -y
  end
  def +@
    self
  end
  def inspect
    "<Vector2D x:#{x}, y:#{y} mag:#{magnitude} angle:#{angle}>"
  end
end