ABS Algorithms for Linear Equations and Linear Least Squares
The Scaled ABS Class: General Properties
ABS methods were introduced by [1], in a paper dealing originally only with solving linear equations via what is now called the basic or unscaled ABS class . The basic ABS class was later generalized to the so-called scaled ABS class and subsequently applied to linear least squares, nonlinear equations and optimization problems, see [2]. Preliminary work has also been initiated concerning Diophantine equations , with possible extensions to combinatorial optimization, and the eigenvalue problem. There are presently (1998) over 350 papers in the ABS field, see [11]. In this contribution we will review the basic properties and results of ABS methods for solving linear determined or underdetermined systems and overdetermined linear systems in the least squares sense.
References
- [1]Abaffy, J., Broyden, C.G., and Spedicato, E.: ‘A class of direct methods for linear systems’, Numerische Math., 45 (1984), 361–376.MathSciNetMATHGoogle Scholar
- [2]Abaffy, J., and Spedicato, E.: ABS projection algorithms: Mathematical techniques for linear and nonlinear equations, Horwood, 1989.Google Scholar
- [3]Bertocchi, M., and Spedicato, E.: ‘Performance of the implicit Gauss—Choleski algorithm of the ABS class on the IBM 3090 VF’: Proc. 10th Symp. Algorithms, Strbske Pleso, 1989, pp. 30–40.Google Scholar
- [4]Bodon, E.: ‘Numerical experiments on the ABS algorithms for linear systems of equations’, Report DMSIA Univ. Bergamo93, no. 17 (1993).Google Scholar
- [5]Broyden, C.G.: ‘On the numerical stability of Huang’s and related methods’, JOTA47 (1985), 401–412.MathSciNetMATHGoogle Scholar
- [6]Daniel, J., Gragg, W.B., Kaufman, L., and Stewart, G.W.: ‘Reorthogonalized and stable algorithms for updating the Gram–Schmidt QR factorization’, Math. Comput.30 (1976), 772–795.MathSciNetMATHGoogle Scholar
- [7]Dennis, J., and Turner, K.: ‘Generalized conjugate directions’, Linear Alg. & Its Appl.88/89 (1987), 187–209.MathSciNetGoogle Scholar
- [8]Galantai, A.: ‘Analysis of error propagation in the ABS class’, Ann. Inst. Statist. Math.43 (1991), 597–603.MathSciNetMATHGoogle Scholar
- [9]Goldfarb, D., and Idnani, A.: ‘A numerically stable dual method for solving strictly convex quadratic programming’, Math. Program.27 (1983), 1–33.MathSciNetMATHGoogle Scholar
- [10]Mirnia, K.: ‘Numerical experiments with iterative refinement of solutions of linear equations by ABS methods’, Report DMSIA Univ. Bergamo32/96 (1996).Google Scholar
- [11]Nicolai, S., and Spedicato, E.: ‘A bibliography of the ABS methods’, OMS8 (1997), 171–183.MATHGoogle Scholar
- [12]Spedicato, E., and Bodon, E.: ‘Solving linear least squares by orthogonal factorization and pseudoinverse computation via the modified Huang algorithm in the ABS class’, Computing42 (1989), 195–205.MathSciNetMATHGoogle Scholar
- [13]Spedicato, E., and Bodon, E.: ‘Numerical behaviour of the implicit QR algorithm in the ABS class for linear least squares’, Ricerca Oper.22 (1992), 43–55.Google Scholar
- [14]Spedicato, E., and Bodon, E.: ‘Solution of linear least squares via the ABS algorithm’, Math. Program.58 (1993), 111–136.MathSciNetMATHGoogle Scholar
- [15]Spedicato, E., and Vespucci, M.T.: ‘Variations on the Gram-Schmidt and the Huang algorithms for linear systems: A numerical study’, Appl. Math. 2 (1993), 81–100.MathSciNetGoogle Scholar
- [16]Wedderburn, J.H.M.: Lectures on matrices, Colloq. Publ. Amer. Math. Soc., 1934.Google Scholar
- [17]Zhang, L.: ‘An algorithm for the least Euclidean norm solution of a linear system of inequalities via the Huang ABS algorithm and the Goldfarb–Idnani strategy’, Report DMSIA Univ. Bergamo95/2 (1995).Google Scholar
