It is shown that in the paper written by M. Froeyen and L. Hellemans [Rev. Sci. Instrum.56, 2325 (1985)], the algorithm POL2*FFT proposed by myself and S. K. Ghosh [S. Sorella and S. K. Ghosh, Rev. Sci. Instrum.55, 1348 (1984)] is used in a incorrect way, because the original paper was not very ‘‘explicit’’ in some steps. Therefore, the new algorithm represents only a different application of our general strategy.