In this paper we consider a class of nonlinear programming problems that arise from the discretization of optimal control problems with bounds on both the state and the control variables. For this class of problems, w...
详细信息
In this paper we consider a class of nonlinear programming problems that arise from the discretization of optimal control problems with bounds on both the state and the control variables. For this class of problems, we analyze constraint qualifications and optimality conditions in detail. We derive an affine-scaling and two primal-dual interior-point Newton algorithms by applying, in an interior-point way, Newton's method to equivalent forms of the first-order optimality conditions. Under appropriate assumptions, the interior-point Newton algorithms are shown to be locally well-defined with a q-quadratic rate of local convergence. By using the structure of the problem, the linear algebra of these algorithms can be reduced to the null space of the Jacobian of the equality constraints. The similarities between the three algorithms are pointed out, and their corresponding versions for the general nonlinear programming problem are discussed.
We develop and analyze a superlinearly convergent affine-scaling interior-point Newton method for infinite-dimensional problems with pointwise bounds in L-p-space. The problem formulation is motivated by optimal contr...
详细信息
We develop and analyze a superlinearly convergent affine-scaling interior-point Newton method for infinite-dimensional problems with pointwise bounds in L-p-space. The problem formulation is motivated by optimal control problems with L-p-controls and pointwise control constraints. The finite-dimensional convergence theory by Coleman and Li [SIAM J. Optim., 6 (1996), pp. 418-445] makes essential use of the equivalence of norms and the exact identifiability of the active constraints close to an optimizer with strict complementarity. Since these features are not available in our infinite-dimensional framework, algorithmic changes are necessary to ensure fast local convergence. The main building block is a Newton-like iteration for an affine-scaling formulation of the KKT-condition. We demonstrate in an example that a stepsize rule to obtain an interior iterate may require very small stepsizes even arbitrarily close to a nondegenerate solution. Using a pointwise projection instead we prove superlinear convergence under a weak strict complementarity condition and convergence with Q-rate >1 under a slightly stronger condition if a smoothing step is available. We discuss how the algorithm can be embedded in the class of globally convergent trust-region interior-point methods recently developed by M. Heinkenschloss and the authors. Numerical results for the control of a heating process confirm our theoretical findings.
We propose a novel approach for the linear adaptive filtering problem using techniques from interiorpoint optimization, The main idea is to formulate a com ex feasibility problem at each iteration and obtain as an es...
详细信息
We propose a novel approach for the linear adaptive filtering problem using techniques from interiorpoint optimization, The main idea is to formulate a com ex feasibility problem at each iteration and obtain as an estimate a filter near the center of the feasible region. It is shown, under some mild conditions, that this algorithm generates a sequence of filters converging to the optimum linear filter at the rate O(1/n), where n is the number of data samples. Furthermore, we show that the algorithm can be made recursive with a per-sample complexity of O(M-2.2), where M is the filter length. The potential of the algorithm for practical applications is demonstrated via numerical simulations where the new algorithm is shown to have superior transient behavior and improved robustness to the source signal statistics when compared to the recursive least-squares (RLS) method.
We are motivated by the problem of constructing a primdi-dual barrier function whose Hessian induces the (theoretically and practically) popular symmetric primal and dual scalings for linear programming problems. Alth...
详细信息
We are motivated by the problem of constructing a primdi-dual barrier function whose Hessian induces the (theoretically and practically) popular symmetric primal and dual scalings for linear programming problems. Although this goal is impossible to attain, we show that the primal-dual entropy function map provide a satisfactory alternative. We study primal-dual interior-point algorithms whose search directions are obtained from a potential function based on this primal-dual entropy barrier. We provide polynomial iteration bounds for these interior-point algorithms. Then we illustrate the connections between the barrier function and a reparametrization of the central path equations. Finally, we consider the possible effects of more general reparametrizations on infeasible-interior-point algorithms.
Two interior-point algorithms using a wide neighborhood of the central path are proposed to solve nonlinear P*-complementarity problems. The proof of the polynomial complexity of the first method requires the problem ...
详细信息
Two interior-point algorithms using a wide neighborhood of the central path are proposed to solve nonlinear P*-complementarity problems. The proof of the polynomial complexity of the first method requires the problem to satisfy a scaled Lipschitz condition. When specialized to monotone complementarity problems, the results of the first method are similar to those in Ref 1. The second method is quite different from the first in that the global convergence proof does not require the scaled Lipschitz assumption. However, at each step of this algorithm, one has to compute an approximate solution of a nonlinear system such that a certain accuracy requirement is satisfied.
A class of affine-scaling interior-point methods for bound constrained optimization problems is introduced which are locally q-superlinear or q-quadratic convergent. It is assumed that the strong second order sufficie...
详细信息
A class of affine-scaling interior-point methods for bound constrained optimization problems is introduced which are locally q-superlinear or q-quadratic convergent. It is assumed that the strong second order sufficient optimality conditions at the solution are satisfied, hut strict complementarity is not required. The methods are modifications of the affine-scaling interior-point Newton methods introduced by T. F. Coleman and Y. Li (Math. Programming, 67, 189-224, 1994). There are two modifications. One is a modification of the scaling matrix, the other one is the use of a projection of the step to maintain strict feasibility rather than a simple scaling of the step. A comprehensive local convergence analysis is given. A simple example is presented to illustrate the pitfalls of the original approach by Coleman and Li in the degenerate case and to demonstrate the performance of the fast converging modifications developed in this paper.
In this paper, we show that Ye-Todd-Mizuno's O(root nL)-iteration homogeneous and self-dual linear programming (LP) algorithm possesses quadratic convergence of the duality gap to zero. In the case of infeasibilit...
详细信息
In this paper, we show that Ye-Todd-Mizuno's O(root nL)-iteration homogeneous and self-dual linear programming (LP) algorithm possesses quadratic convergence of the duality gap to zero. In the case of infeasibility, this shows that a homogenizing variable quadratically converges to zero (which proves that at least one of the primal and dual LP problems is infeasible) and implies that the iterates of the (original) LP variable quadratically diverge. Thus, we have established a complete asymptotic convergence result for interior-point algorithms without any assumption on the LP problem.
Recently, Resende and Veiga [SIAM J. Optim., 3 (1993), pp. 516-537] proposed an efficient implementation of the dual affine (DA) interior-point algorithm for the solution of Linear transportation models with integer c...
详细信息
Recently, Resende and Veiga [SIAM J. Optim., 3 (1993), pp. 516-537] proposed an efficient implementation of the dual affine (DA) interior-point algorithm for the solution of Linear transportation models with integer costs and right-hand-side coefficients, This procedure incorporates a preconditioned conjugate gradient (PCG) method for solving the linear system that is required in each iteration of the DA algorithm. In this paper, we introduce an incomplete QR decomposition (IQRD) preconditioning for the PCG algorithm, Computational experience shows that the IQRD preconditioning is appropriate in this instance and is more efficient than the preconditioning introduced by Resende and Veiga. We also show that the primal dual (PD) and the predictor corrector (PC) interior-point algorithms can also be implemented by using the same type of technique. A comparison among these three algorithms is Included and indicates that the PD and PC algorithms are more appropriate for the solution of transportation problems with well-scaled cost and right-hand-side coefficients and assignment problems with poorly scaled cost coefficients. On the other hand, the DA algorithm seems to be more efficient for assignment problems with well-scaled cost coefficients and transportation problems whose cost coefficients are badly scaled.
作者:
Zhang, YRice Univ
Dept Computat & Appl Math Houston TX 77005 USA
In this paper, we describe our implementation of a primal-dual infeasible-interior-point algorithm for large-scale linear programming under the MATLAB environment. The resulting software is called LIPSOL - Linear-prog...
详细信息
In this paper, we describe our implementation of a primal-dual infeasible-interior-point algorithm for large-scale linear programming under the MATLAB environment. The resulting software is called LIPSOL - Linear-programming interior-point SOLvers. LIPSOL is designed to take the advantages of MATLAB's sparse-matrix functions and external interface facilities, and of existing Fortran sparse Cholesky codes. Under the MATLAB environment, LIPSOL inherits a high degree of simplicity and versatility in comparison to its counterparts in Fortran or C language. More importantly, our extensive computational results demonstrate that LIPSOL also attains an impressive performance comparable with that of efficient Fortran or C codes in solving large-scale problems. In addition, we discuss in detail a technique for overcoming numerical instability in Cholesky factorization at the end-stage of iterations in interior-point algorithms.
This paper describes a new trust region method for solving large-scale optimization problems with nonlinear equality and inequality constraints. The new algorithm employs interior-point techniques from linear programm...
详细信息
This paper describes a new trust region method for solving large-scale optimization problems with nonlinear equality and inequality constraints. The new algorithm employs interior-point techniques from linear programming, adapting them for more general nonlinear problems. A software implementation based entirely on sparse matrix methods is described. The software handles infeasible start points, identifies the active set of constraints at a solution, and can use second derivative information to solve problems. Numerical results are reported for large and small problems, and a comparison is made with other large-scale optimization codes.
暂无评论