def calc_yaw(self, s):
    '\n        calc yaw\n        '
    dx = self.sx.calcd(s)
    dy = self.sy.calcd(s)
    yaw = math.atan2(dy, dx)
    return yaw
calc yaw
def calc_yaw(self, s):
    '\n        \n        '
    dx = self.sx.calcd(s)
    dy = self.sy.calcd(s)
    yaw = math.atan2(dy, dx)
    return yaw