 These two types of transformation don't compress the matrix, but keep its size unchanged.However, in a number of cases their application allows to reduce the matrix's size by some of the above-mentioned compression operators.Hence there is a variety of matrix compression operators performed in polynomial time and preserving the Hamiltonian cycle polynomial in characteristic 2 whose sequential application, together with the transpose transformation (utilized each time the operators leave the matrix intact), has, for each matrix, a certain limit that can be defined as the compression-closure operator.