code: def gps_velocity_df(GPS):
      '''return GPS velocity vector'''
      vx = GPS.Spd * cos(radians(GPS.GCrs))
      vy = GPS.Spd * sin(radians(GPS.GCrs))
      return Vector3(vx, vy, GPS.VZf gps_velocity_df(GPS):
      '''return GPS velocity vector'''
      vx = GPS.Spd * cos(radians(GPS.GCrs))
      vy = GPS.Spd * sin(radians(GPS.GCrs))
      return Vector3(vx, vy, GPS.VZ)
docs: return GPS velocity vector