Which variables of a numerical problem cause ill-conditioning?

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autore principale: Dewaele, Nick
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866916662878404608
author Dewaele, Nick
author_facet Dewaele, Nick
contents We study a broad class of numerical problems that can be defined as the solution of a system of (nonlinear) equations for a subset of the dependent variables. Given a system of the form $F(x,y,z) = c$ with multivariate input $x$ and dependent variables $y$ and $z$, we define and give concrete expressions for the condition number of solving for a value of $y$ such that $F(x,y,z) = c$ for some unspecified $z$. This condition number can be used to determine which of the dependent variables of a numerical problem are the most ill-conditioned. We show how this can be used to explain the condition number of the problem of solving for all dependent variables, even if the solution is not unique. The concepts are illustrated with Tucker decomposition of tensors as an example problem.
format Preprint
id arxiv_https___arxiv_org_abs_2503_20437
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Which variables of a numerical problem cause ill-conditioning?
Dewaele, Nick
Numerical Analysis
15A12, 15A23, 49Q12, 53B20, 15A69, 65F35
We study a broad class of numerical problems that can be defined as the solution of a system of (nonlinear) equations for a subset of the dependent variables. Given a system of the form $F(x,y,z) = c$ with multivariate input $x$ and dependent variables $y$ and $z$, we define and give concrete expressions for the condition number of solving for a value of $y$ such that $F(x,y,z) = c$ for some unspecified $z$. This condition number can be used to determine which of the dependent variables of a numerical problem are the most ill-conditioned. We show how this can be used to explain the condition number of the problem of solving for all dependent variables, even if the solution is not unique. The concepts are illustrated with Tucker decomposition of tensors as an example problem.
title Which variables of a numerical problem cause ill-conditioning?
topic Numerical Analysis
15A12, 15A23, 49Q12, 53B20, 15A69, 65F35
url https://arxiv.org/abs/2503.20437