And just to tell you again that is a strange partial differential equation relating these two vector fields.

再说明一下，这是关于这两个向量场，多少有点奇怪的偏微分方程。

youdao

And just to tell you again that is a strange partial differential equation relating these two vector fields.

再说明一下，这是关于这两个向量场，多少有点奇怪的偏微分方程。

youdao