Two side bounds on the inverses of diagonally dominant tridiagonal matrices
نویسنده
چکیده
We establish upper and lower bounds for the entries of the inverses of diagonally dominant tridiagonal matrices. These bounds improve the bounds recently given by Shivakumar and Ji. Moreover, we show how to improve our bounds iteratively. For an n n M{matrix this iterative reenement yields the exact inverse after n ? 1 steps.
منابع مشابه
A Note on Estimates of Diagonal Elements of the Inverse of Diagonally Dominant Tridiagonal Matrices
In this note we show how to improve some recent upper and lower bounds for the elements of the inverse of diagonally dominant tridiagonal matrices. In particular, a technique described by [R. Peluso, and T. Politi, Some improvements on two-sided bounds on the inverse of diagonally dominant tridiagonal matrices, Lin. Alg. Appl. Vol. 330 (2001) 1-14], is used to obtain better bounds for the diago...
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