The method, firstly, grids the precipitation amount by conicoid, then judges and traces isoline and brings forward a way of how to avoid connection uncertainty of isoline.

• 该方法首先用二次曲面对不规则站点雨量进行格网化，然后在格网上对等雨量点进行判断、追踪以及在追踪过程中如何消除追踪的二义性。