This paper describes a new method of QR-decomposition of square nonsingular matrices (real or complex) by the Givens rotations through the unitary discrete heap transforms. This transforms can be defined by a different path, or the order of processing components of input data, which leads to different realizations of the QR-decomposition. The heap transforms are fast, because of a simple form of decomposition of their matrices. The direct calculation of the N-point discrete heap transform

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... es no more than 5(N − 1) multiplications, 2(N − 1) additions, plus 3(N − 1) trigonometric operations. The QR-decomposition of the square matrix N × N uses about 4/3N 3