Locating Eigenvalues of a Symmetric Matrix whose Graph is Unicyclic

Autores

  • R. O. Braga Universidade do Vale do Rio dos Sinos https://orcid.org/0000-0002-6156-2213
  • V. M. Rodrigues Departamento de Matemática Pura e Aplicada, IME- Instituto de Matemática e Estatística UFRGS - Universidade Federal do Rio Grande do Sul https://orcid.org/0000-0002-1964-3327
  • R. O. Silva Departamento de Matemática Pura e Aplicada, IME- Instituto de Matemática e Estatística UFRGS - Universidade Federal do Rio Grande do Sul

DOI:

https://doi.org/10.5540/tcam.2021.022.04.00659

Palavras-chave:

Symmetric matrix, eigenvalue location, unicyclic graph.

Resumo

We present a linear-time algorithm that computes in a given real interval the number of eigenvalues of any symmetric matrix whose underlying graph is unicyclic. The algorithm can be applied to vertex- and/or edge-weighted or unweighted unicyclic graphs. We apply the algorithm to obtain some general results on the spectrum of a generalized sun graph for certain matrix representations which include the Laplacian, normalized Laplacian and signless Laplacian matrices.

Biografia do Autor

R. O. Braga, Universidade do Vale do Rio dos Sinos

Doutor em Matemática Aplicada (UFRGS, 2015)

Referências

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R. O. Braga, V. M. Rodrigues, and V. Trevisan. Locating eigenvalues of unicyclicgraphs.Appl. Anal. Discrete Math., 11(2):273–298, 2017.

F. R. K. Chung.Spectral Graph Theory. American Mathematical Society, 1997.

P. J. Davis.Circulant matrices. John Wiley & Sons, New York-Chichester-Brisbane, 1979. A Wiley-Interscience Publication, Pure and Applied Mathe-matics.

D. P. Jacobs and V. Trevisan. Locating the eigenvalues of trees.Linear AlgebraAppl., 434(1):81–88, 2011.

R. Merris. Laplacian matrices of graphs: a survey. volume 197/198, pages143–176. 1994. Second Conference of the International Linear Algebra Society(ILAS) (Lisbon, 1992)

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Publicado

2021-10-26

Como Citar

Braga, R. O., Rodrigues, V. M., & Silva, R. O. (2021). Locating Eigenvalues of a Symmetric Matrix whose Graph is Unicyclic. Trends in Computational and Applied Mathematics, 22(4), 659–674. https://doi.org/10.5540/tcam.2021.022.04.00659

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Artigo Original