Iterative Optimization of Multidimensional Functions on Turing Machines under Performance Guarantees

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Boche, Holger, Pohl, Volker, Poor, H. Vincent
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917899673796608
author Boche, Holger
Pohl, Volker
Poor, H. Vincent
author_facet Boche, Holger
Pohl, Volker
Poor, H. Vincent
contents This paper studies the effective convergence of iterative methods for solving convex minimization problems using block Gauss--Seidel algorithms. It investigates whether it is always possible to algorithmically terminate the iteration in such a way that the outcome of the iterative algorithm satisfies any predefined error bound. It is shown that the answer is generally negative. Specifically, it is shown that even if a computable continuous function which is convex in each variable possesses computable minimizers, a block Gauss--Seidel iterative method might not be able to effectively compute any of these minimizers. This means that it is impossible to algorithmically terminate the iteration such that a given performance guarantee is satisfied. The paper discusses two reasons for this behavior. First, it might happen that certain steps in the Gauss--Seidel iteration cannot be effectively implemented on a digital computer. Second, all computable minimizers of the problem may not be reachable by the Gauss--Seidel method. Simple and concrete examples for both behaviors are provided.
format Preprint
id arxiv_https___arxiv_org_abs_2501_13038
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Iterative Optimization of Multidimensional Functions on Turing Machines under Performance Guarantees
Boche, Holger
Pohl, Volker
Poor, H. Vincent
Optimization and Control
Computational Complexity
This paper studies the effective convergence of iterative methods for solving convex minimization problems using block Gauss--Seidel algorithms. It investigates whether it is always possible to algorithmically terminate the iteration in such a way that the outcome of the iterative algorithm satisfies any predefined error bound. It is shown that the answer is generally negative. Specifically, it is shown that even if a computable continuous function which is convex in each variable possesses computable minimizers, a block Gauss--Seidel iterative method might not be able to effectively compute any of these minimizers. This means that it is impossible to algorithmically terminate the iteration such that a given performance guarantee is satisfied. The paper discusses two reasons for this behavior. First, it might happen that certain steps in the Gauss--Seidel iteration cannot be effectively implemented on a digital computer. Second, all computable minimizers of the problem may not be reachable by the Gauss--Seidel method. Simple and concrete examples for both behaviors are provided.
title Iterative Optimization of Multidimensional Functions on Turing Machines under Performance Guarantees
topic Optimization and Control
Computational Complexity
url https://arxiv.org/abs/2501.13038