code: def mag_roll(RAW_IMU, inclination, declination):
      '''estimate roll from mag'''
      m = mag_rotation(RAW_IMU, inclination, declination)
      (r, p, y) = m.to_euler()
      return degrees(rf mag_roll(RAW_IMU, inclination, declination):
      '''estimate roll from mag'''
      m = mag_rotation(RAW_IMU, inclination, declination)
      (r, p, y) = m.to_euler()
      return degrees(r)
docs: estimate roll from mag