What does the stupid fish on Yin Hang and Yang Tai's door mean?

Yin and yang fish, that is, Tai Chi map. It depends on where it is hung at home. First, if it is hung on the door, facing outward, or above the window, it will be seen by the Yin and Yang teachers and feel the landscape outside, or the architectural trend of other people's homes, which is not good for themselves and is used for harmony. Second, if it is hung in a house, somewhere, it means this house.