Abstract: Based on Wu’s elimination method and “divide-and-conquer” strategy, the undetermined coefficient method for constructing polynomial conservation laws of nonlinear differential-difference equations was improved. Furthermore, a Maple package CLawDDEs was developed to automatically derive conserved densities and associated fluxes of polynomial differential-difference equations. For parameterized nonlinear
differential-difference equations, CLawDDEs can also filter out the compatibility conditions which admit the existence of infinitely conservation laws. So CLawDDEs can be used as an effective tool to test the integrability of nonlinear differential-difference equations.

Key words: conservation laws, scaling invariance, integrability, symbolic computation, differential-difference equations, conservation laws, scaling invariance, integrability, symbolic computation