abstract: We wish to present a generic method to investigate many-body continuous-variable systems. It is based on the notion of matrix product states and the algorithms thereof. The method is quite versatile and can be applied to a wide variety of situations. We wish to show how it provides reliable results in the computation of fundamental properties of a chain of quantum harmonic oscillators or of the one-dimensional quantum rotor model. We also would like to present a spin-off application of the method: an iterative technique to efficiently get numerical solutions of partial differential equations of many variables