In this article, exact solutions of two (3+1)-dimensional nonlinear differential equations are derived by using the complex method. We change the (3+1)-dimensional B-type Kadomtsev-Petviashvili (BKP) equation and generalized shallow water (gSW) equation into the complex differential equations by applying traveling wave transform and show that meromorphic solutions of these complex differential equations belong to class W, and then, we get exact solutions of these two (3+1)-dimensional equations.

中文翻译：

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关于两（3 + 1）维非线性微分方程的精确解

在本文中，使用复杂方法导出了二维（3 + 1）非线性微分方程的精确解。通过行波变换将（3 + 1）维B型Kadomtsev-Petviashvili（BKP）方程和广义浅水（gSW）方程转换为复微分方程，证明这些复微分方程的亚纯解属于W类，然后，我们得到这两个（3 + 1）维方程的精确解。