
Accession Number : AD0659294
Title : FUNCTION MINIMIZATION WITHOUT DERIVATIVES BY A SEQUENCE OF QUADRATIC PROGRAMMING PROBLEMS.
Descriptive Note : Technical rept.,
Corporate Author : HARVARD UNIV CAMBRIDGE MASS DIV OF ENGINEERING AND APPLIED PHYSICS
Personal Author(s) : Winfield,David H.
Report Date : AUG 1967
Pagination or Media Count : 22
Abstract : An algorithm is described for minimizing an arbitrary scalar cost function c(x) with respect to an nvector x. At each stage of the minimization, the cost function is approximated by a quadratic form in the region about the current lowestcost point. The next trial point is taken as the minimum of this quadratic form within a hypercube in nspace centered at the current lowestcost point. The procedure has quadratic convergence, but differs from other quadratically convergent minimization algorithms in that (1) minimization is over a sequence of ndimensional regions rather than over a sequence of onedimensional straight lines (2) the local approximation to the cost surface need not be positive definite (3) each approximation depends only on true cost values and is independent of prior approximations (4) after each evaluation of cost at a trial point, the trial point is added, and a point distant from the current lowestcost point is deleted, from the set of points to which the next quadratic form will interpolate. The algorithm takes relatively large steps, and is forced by (4) to learn from its failures. Test results are presented for N  2 using Rosenbrock's parabolic valley as the cost function. (Author)
Descriptors : (*QUADRATIC PROGRAMMING, OPTIMIZATION), (*COSTS, MATHEMATICAL MODELS), ALGORITHMS, NONLINEAR PROGRAMMING, MATHEMATICAL PROGRAMMING, CONVERGENCE
Subject Categories : Operations Research
Distribution Statement : APPROVED FOR PUBLIC RELEASE