# Approximation of double Walsh–Fourier series by means of the matrix transform

### Abstract

UDC 517.5

We discuss the rate of approximation of partial sums of the double Walsh–Fourier series in the spaces $L^p(G^2),$ $1\leq p <\infty,$ and $C(G^2)$ by the matrix transform.

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*Ukrains’kyi Matematychnyi Zhurnal*, Vol. 76, no. 5, June 2024, pp. 664 -79, doi:10.3842/umzh.v76i5.7397.

Copyright (c) 2024 István Blahota

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