What is the partial cleaning mode of Mi Robot Vacuum?

Explanation:
When the Mi Robot Vacuum is on standby or suspended, long press the home button to start partial cleaning. This mode mainly uses the square area with the center of the robot at 1.5m x 1.5m. When the cleaning is finished, the robot will automatically return to the starting point and stop working, without automatically backrushing.
Notes:
Starting the partial sweep will redraw the map, so the sweep will be finished after starting the partial sweep during the execution of the sweep, after the partial sweep finish, it will return to the starting point of the partial sweep.
Note: Partial sweep records will not be recorded in the sweep record.