An alternative theoretical approach for solving the time-dependent Schro dinger equation for atoms in an intense laser field is presented.In this method the time-dependent wave function is expanded in a basis set but the expansion coefficients are determined by linear-least-squares fitting of the wave function on discrete mesh points in configuration space,thus avoiding the need of evaluating a large number of matrix elements.We illustrate the method by computing wave functions,above-threshold ionization spectra,and harmonic generation spectra of a model atom and compare the results with those obtained using the split-operator method.