{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,2,21]],"date-time":"2025-02-21T19:14:05Z","timestamp":1740165245835,"version":"3.37.3"},"reference-count":26,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2018,11,9]],"date-time":"2018-11-09T00:00:00Z","timestamp":1541721600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Axioms"],"abstract":"The generalized Schur algorithm is a powerful tool allowing to compute classical decompositions of matrices, such as the Q R and L U factorizations. When applied to matrices with particular structures, the generalized Schur algorithm computes these factorizations with a complexity of one order of magnitude less than that of classical algorithms based on Householder or elementary transformations. In this manuscript, we describe the main features of the generalized Schur algorithm. We show that it helps to prove some theoretical properties of the R factor of the Q R factorization of some structured matrices, such as symmetric positive definite Toeplitz and Sylvester matrices, that can hardly be proven using classical linear algebra tools. Moreover, we propose a fast implementation of the generalized Schur algorithm for computing the rank of Sylvester matrices, arising in a number of applications. Finally, we propose a generalized Schur based algorithm for computing the null-space of polynomial matrices.<\/jats:p>","DOI":"10.3390\/axioms7040081","type":"journal-article","created":{"date-parts":[[2018,11,13]],"date-time":"2018-11-13T08:27:31Z","timestamp":1542097651000},"page":"81","source":"Crossref","is-referenced-by-count":3,"title":["The Generalized Schur Algorithm and Some Applications"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2046-0456","authenticated-orcid":false,"given":"Teresa","family":"Laudadio","sequence":"first","affiliation":[{"name":"Istituto per le Applicazioni del Calcolo \u201cM. Picone\u201d, CNR, Sede di Bari, via G. Amendola 122\/D, 70126 Bari, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0045-2862","authenticated-orcid":false,"given":"Nicola","family":"Mastronardi","sequence":"additional","affiliation":[{"name":"Istituto per le Applicazioni del Calcolo \u201cM. Picone\u201d, CNR, Sede di Bari, via G. Amendola 122\/D, 70126 Bari, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0115-9932","authenticated-orcid":false,"given":"Paul","family":"Van Dooren","sequence":"additional","affiliation":[{"name":"Catholic University of Louvain, Department of Mathematical Engineering, Avenue Georges Lemaitre 4, B-1348 Louvain-la-Neuve, Belgium"}]}],"member":"1968","published-online":{"date-parts":[[2018,11,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Kailath, T., and Sayed, A.H. (1999). Fast Reliable Algorithms for Matrices with Structure, SIAM.","DOI":"10.1137\/1.9781611971354"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1137\/1037082","article-title":"Displacement Structure: Theory and Applications","volume":"32","author":"Kailath","year":"1995","journal-title":"SIAM Rev."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"950","DOI":"10.1137\/S0895479895287419","article-title":"Stabilizing the Generalized Schur Algorithm","volume":"17","author":"Chandrasekaran","year":"1996","journal-title":"SIAM J. Matrix Anal. Appl."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"104","DOI":"10.1137\/S089547989528692X","article-title":"Stability issues in the factorization of structured matrices","volume":"18","author":"Stewart","year":"1997","journal-title":"SIAM J. Matrix Anal. Appl."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"560","DOI":"10.1007\/3-540-45262-1_66","article-title":"On the stability of the generalized Schur algorithm","volume":"1988","author":"Mastronardi","year":"2001","journal-title":"Lect. Notes Comput. Sci."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"212","DOI":"10.1016\/j.cam.2007.01.032","article-title":"A structured rank-revealing method for Sylvester matrix","volume":"213","author":"Li","year":"2008","journal-title":"J. Comput. Appl. Math."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"493","DOI":"10.1137\/0313029","article-title":"Minimal bases of rational vector spaces with applications to multivariable linear systems","volume":"13","author":"Forney","year":"1975","journal-title":"SIAM J. Control Optim."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"256","DOI":"10.1016\/j.amc.2008.10.037","article-title":"An improved Toeplitz algorithm for polynomial matrix null-space computation","volume":"207","author":"Henrion","year":"2009","journal-title":"Appl. Math. Comput."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"217","DOI":"10.1016\/0167-6911(88)90010-2","article-title":"A new method for computing a column reduced polynomial matrix","volume":"10","author":"Beelen","year":"1988","journal-title":"Syst. Control Lett."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"569","DOI":"10.1016\/0024-3795(93)90480-C","article-title":"Column reduction of polynomial matrices","volume":"188","author":"Neven","year":"1993","journal-title":"Linear Algebra Its Appl."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"210","DOI":"10.1137\/0908031","article-title":"A note on downdating the Cholesky factorization","volume":"8","author":"Brent","year":"1987","journal-title":"SIAM J. Sci. Stat. Comput."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"504","DOI":"10.1137\/S0036144502414930","article-title":"J-orthogonal matrices: properties and generation","volume":"45","author":"Higham","year":"2003","journal-title":"SIAM Rev."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"371","DOI":"10.1023\/A:1019116520737","article-title":"Fast algorithm for solving the Hankel\/Toeplitz Structured Total Least Squares Problem","volume":"23","author":"Lemmerling","year":"2000","journal-title":"Numer. Algorithm."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"533","DOI":"10.1137\/S0895479898345813","article-title":"Fast structured total least squares algorithm for solving the basic deconvolution problem","volume":"22","author":"Mastronardi","year":"2000","journal-title":"SIAM J. Matrix Anal. Appl."},{"key":"ref_15","unstructured":"Golub, G.H., and Van Loan, C.F. (2013). Matrix Computations, Johns Hopkins University Press. [4th ed.]."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Boito, P. (2011). Structured Matrix Based Methods for Approximate Polynomial GCD, Edizioni Della Normale.","DOI":"10.1007\/978-88-7642-381-9"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1007\/978-3-7643-8996-3_6","article-title":"A Fast Algorithm for Approximate Polynomial GCD Based on Structured Matrix Computations","volume":"Volume 199","author":"Bini","year":"2010","journal-title":"Numerical Methods for Structured Matrices and Applications"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1016\/j.laa.2004.07.006","article-title":"Implementation of the regularized structured total least squares algorithms for blind image deblurring","volume":"391","author":"Mastronardi","year":"2004","journal-title":"Linear Algebra Its Appl."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"287","DOI":"10.1016\/j.laa.2003.11.030","article-title":"A robust solution of the generalized polynomial Bezout identity","volume":"385","author":"Basilio","year":"2004","journal-title":"Linear Algebra Its Appl."},{"key":"ref_20","unstructured":"Kailath, T. (1980). Linear Systems, Prentice Hall."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"463","DOI":"10.1137\/100816808","article-title":"Recovery of Eigenvectors and Minimal Bases of Matrix Polynomials from Generalized Fiedler Linearizations","volume":"32","author":"Bueno","year":"2011","journal-title":"SIAM J. Matrix Anal. Appl."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"2181","DOI":"10.1137\/090772927","article-title":"Fiedler companion linearizations and the recovery of minimal indices","volume":"31","author":"Dopico","year":"2010","journal-title":"SIAM J. Matrix Anal. Appl."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"343","DOI":"10.1016\/0024-3795(95)00649-4","article-title":"High performance algorithms for Toeplitz and block Toeplitz matrices","volume":"241\u2013243","author":"Gallivan","year":"1996","journal-title":"Linear Algebra Its Appl."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"497","DOI":"10.1016\/S0024-3795(96)00517-4","article-title":"Cholesky Factorization of Semi-definite Toeplitz Matrices","volume":"254","author":"Stewart","year":"1997","journal-title":"Linear Algebra Its Appl."},{"key":"ref_25","first-page":"151","article-title":"On the computation of the null space of Toeplitz-like matrices","volume":"33","author":"Mastronardi","year":"2009","journal-title":"Electron. Trans. Numer. Anal."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"264","DOI":"10.1016\/j.laa.2005.03.017","article-title":"Numerical computation of minimal polynomial bases: A generalized resultant approach","volume":"405","author":"Antoniou","year":"2005","journal-title":"Linear Algebra Its Appl."}],"container-title":["Axioms"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2075-1680\/7\/4\/81\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,6,13]],"date-time":"2024-06-13T13:56:23Z","timestamp":1718286983000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2075-1680\/7\/4\/81"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,11,9]]},"references-count":26,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2018,12]]}},"alternative-id":["axioms7040081"],"URL":"https:\/\/doi.org\/10.3390\/axioms7040081","relation":{},"ISSN":["2075-1680"],"issn-type":[{"type":"electronic","value":"2075-1680"}],"subject":[],"published":{"date-parts":[[2018,11,9]]}}}