Accuracy of an approximate variational solution procedure for the nonlinear Schrödinger equation

Abstract
An assessment is made of the accuracy of a direct variational method for obtaining approximate analytical solutions of the nonlinear Schrödinger equation. The method involves trial functions and a Rayleigh-Ritz optimization procedure. The accuracy of the approximation scheme is inferred from the ability of the optimized solution to preserve the invariants of the nonlinear Schrödinger equation.