Approximation of signals of class Lip(α, p) by linear operators

Mittal, Rhoades 5], 6], 7] and 8] and Mittal et al. 9] and 10] have initiated a study of error estimates E_n(f) through trigonometric-Fourier approximation (tfa) for the situations in which the summability matrix T does not have monotone rows. In this paper we continue the work. Here we extend two theorems of Leindler 4], where he has weakened the conditions on {p_n} given by Chandra 2], to more general classes of triangular matrix methods. Our Theorem also partially generalizes Theorem 4 of Mittal et al. 11] by dropping the monotonicity on the elements of matrix rows, which in turn generalize the results of Quade 15].