Understanding the ultraspherical spectral method

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Cheng, Lu, Xu, Kuan
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911882051321856
author Cheng, Lu
Xu, Kuan
author_facet Cheng, Lu
Xu, Kuan
contents The ultraspherical spectral method features high accuracy and fast solution. In this article, we determine the sources of error arising from the ultraspherical spectral method and derive its effective condition number, which explains why its backward error is consistent with a numerical method with bounded condition number. In addition, we show the cause for the Cauchy error to go below the machine epsilon and decay eventually to exact zero, revealing the fact that the Cauchy error can be misleading when used as an indicator of convergence and accuracy. The analysis in this work can be readily extended to other spectral methods, when applicable, and to the solution of PDEs.
format Preprint
id arxiv_https___arxiv_org_abs_2405_11847
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Understanding the ultraspherical spectral method
Cheng, Lu
Xu, Kuan
Numerical Analysis
15A12, 65L07, 65L10, 65L20, 65L70
The ultraspherical spectral method features high accuracy and fast solution. In this article, we determine the sources of error arising from the ultraspherical spectral method and derive its effective condition number, which explains why its backward error is consistent with a numerical method with bounded condition number. In addition, we show the cause for the Cauchy error to go below the machine epsilon and decay eventually to exact zero, revealing the fact that the Cauchy error can be misleading when used as an indicator of convergence and accuracy. The analysis in this work can be readily extended to other spectral methods, when applicable, and to the solution of PDEs.
title Understanding the ultraspherical spectral method
topic Numerical Analysis
15A12, 65L07, 65L10, 65L20, 65L70
url https://arxiv.org/abs/2405.11847