Applications of the Jacobi elliptic function method to special-type nonlinear equations

The Jacobi elliptic function method with symbolic computation is extended to special-type nonlinear equations for constructing their doubly periodic wave solutions. Such equations cannot be directly dealt with by the method and require some kinds of pre-possessing techniques. It is shown that soliton solutions and triangular solutions can be established as the limits of the Jacobi doubly periodic wave solutions. The different Jacobi function expansions may lead to new Jacobi doubly periodic wave solutions, triangular periodic solutions and soliton solutions. In addition, as an illustrative sample, the properties for the Jacobi doubly periodic wave solutions of the coupled Schrodinger-KdV equation are shown with some figures. (C) 2002 Elsevier Science B.V. All tights reserved.