Title
dqds with Aggressive Early Deflation
Abstract
The dqds algorithm computes all the singular values of an $n \times n$ bidiagonal matrix to high relative accuracy in $O(n^2)$ cost. Its efficient implementation is now available as a LAPACK subroutine and is the preferred algorithm for this purpose. In this paper we incorporate into dqds a technique called aggressive early deflation, which has been applied successfully to the Hessenberg QR algorithm. Extensive numerical experiments show that aggressive early deflation often reduces the dqds runtime significantly. In addition, our theoretical analysis suggests that with aggressive early deflation, the performance of dqds is largely independent of the shift strategy. We confirm through experiments that the zero-shift version is often as fast as the shifted version. We give a detailed error analysis to prove that with our proposed deflation strategy, dqds computes all the singular values to high relative accuracy.
Year
DOI
Venue
2012
10.1137/110821330
SIAM J. Matrix Analysis Applications
Keywords
Field
DocType
preferred algorithm,detailed error analysis,proposed deflation strategy,high relative accuracy,aggressive early deflation,shift strategy,dqds algorithm,theoretical analysis,singular value,hessenberg qr algorithm,singular values,bidiagonal matrix,matrix theory
Mathematical optimization,Singular value,Subroutine,Matrix (mathematics),Bidiagonal matrix,Deflation,Mathematics,QR algorithm
Journal
Volume
Issue
ISSN
33
1
0895-4798
Citations 
PageRank 
References 
3
0.45
11
Authors
3
Name
Order
Citations
PageRank
Yuji Nakatsukasa19717.74
Kensuke Aishima2134.05
Ichitaro Yamazaki317425.27