Abstract
The CGS (conjugate Gram-Schmidt) algorithms of Hestenes and Stiefel are formulated so as to obtain least-square solutions of a system of equationsg(x)=0 inn independent variables. Both the linear caseg(x)=Ax−h and the nonlinear case are discussed. In the linear case, a least-square solution is obtained in no more thann steps, and a method of obtaining the least-square solution of minimum length is given. In the nonlinear case, the CGS algorithm is combined with the Gauss-Newton process to minimize sums of squares of nonlinear functions. Results of numerical experiments with several versions of CGS on test functions indicate that the algorithms are effective.
Similar content being viewed by others
References
Hestenes, M. R., andStiefel, E.,Methods of Conjugate Gradients for Solving Linear Systems, Journal of Research of the National Bureau of Standards, Section B, Vol. 49, No. 6, 1952.
Dennemeyer, R. F., andMookini, E. H.,CGS Algorithms for Unconstrained Minimization of Functions, Journal of Optimization Theory and Applications, Vol. 16, Nos. 1–2, 1975.
Hestenes, M. R.,Pseudoinverses and Conjugate Gradients, Communications of the ACM, Vol. 18, No. 1, 1975.
Ortega, J., andRheinboldt, W.,Itrative Solution of Nonlinear Equations in Several Variables, Academic Press, New York, New York, 1970.
Fletcher, R., andPowell, M.,A Rapidly Convergent Descent Method for Minimization, Computer Journal, Vol. 6, No. 2, 1964.
Beale, E.,On an Iterative Method of Finding a Local Minimum of a Function of More Than One Variable, Princeton University, Statistical Techniques Research Group, Technical Report No. 25, 1958.
Cragg, E., andLevy, A.,Study on a Supermemory Gradient Method for the Minimization of Functions, Journal of Optimization Theory and Applications, Vol. 4, pp. 191–205, 1969.
Kowlik, J., andOsborne, M.,Methods for Unconstrained Optimization Problems, American Elsevier Publishing Company, New York, New York, 1968.
Box, M.,A Comparison of Several Current Optimization Methods and the Use of Transformations in Constrained Problems, Computer Journal, Vol. 9, 1966.
Bard, Y.,Comparison of Gradient Methods for the Solution of Nonlinear Parametric Estimation Problems, SIAM Journal of Numerical Analysis, Vol. 7, pp. 159–186, 1970.
Author information
Authors and Affiliations
Additional information
Communicated by M. R. Hestenes
The author wishes to express appreciation and to acknowledge the ideas and help of Professor M. R. Hestenes which made this paper possible.
Rights and permissions
About this article
Cite this article
Dennemeyer, R.F. Extensions of CGS algorithms: Generalized least-square solutions. J Optim Theory Appl 24, 387–419 (1978). https://doi.org/10.1007/BF00932885
Issue Date:
DOI: https://doi.org/10.1007/BF00932885