| The upper bound estimation of the infinit y norm for the inverse matrix of a nonsingular matrix is widel y used in solving linear equations.In this thesis,we stud y the estimation s of the infinit y norm upper bound for the inverse of the doubly strictly diagonally dominant(DSDD)matrices.Firstly,we transform the DSDD matrices into the form of multiplication of three special matrices by using Schur complement technique,then a new upper bound of the infinity norm of the inverse of the Schur complement of DSDD matrices is given.Secondly,based on this result,a new upper bound of the infinity norm of DSDD matrices is given.Finally,a numerical example is given to illustrate that the results obtained in this thesis improve some existing results. |
