Approximations of Sturm–Liouville eigenvalues using differential quadrature (DQ) method

The polynomial-based differential quadrature (PDQ) and the Fourier expansion-based differential quadrature (FDQ) methods are applied in this work to compute eigenvalues of the Sturm–Liouville problem. It is demonstrated through some examples that accurate results for the first kkth eigenvalues of the problem, where k=1,2,3,…,k=1,2,3,…, can be obtained by using (at least) 2k2k mesh points. The results of this work are compared with other published results in the literature.