How to judge the type of weather system on isobar distribution map

Isobar bends and closes, and the value decreases gradually from the outside to the inside, which is a cyclone; The value gradually increases from the outside to the inside, which is an anticyclone.

Several isobars are close to one of them, and the distance between isobars gradually decreases, indicating that the pressure difference gradually increases, indicating that there is a front. The front isobar bends to the side with large value, which is a warm front; Bending to the side with small value is a cold front.