Home Page
Original Matrices
Serial Performance
Parallel Performance

Computing Aproximate Eigensystems (CApE)



Purpose:
To develop efficient methods for approximating eigenvalues and eigenvectors of a symmetric matrix A that is block tridiagonal, banded, or the magnitudes of its elements rapidly decrease when moving away from the diagonal. More specifically, given a relative error parameter , the objective is to develop and implement efficient methods for finding approximations to all or a subset of the eigenvalues and eigenvectors of the matrix A such that:
  •     with     ,
    where the diagonal matrix contains the approximations to the eigenvalues of A and the column vectors of are the approximations to the eigenvectors of A.
  • the eigenvectors are numerically orthogonal, and
  • their computational complexity is reduced significantly (by one or two orders of magnitude) compared to computing "exact" (except for rounding errors) eigenvalues and eigenvectors.


  • Research Leader:
    Robert C. Ward

    Collaborators:
    Yihua Bai, Indiana State University
    Wilfried Gansterer, University of Vienna
    Rick Muller, Sandia National Laboratories, Albuquerque
    George Fann, Oak Ridge National Laboratory
    Bill Goddard, California Institute of Technology
    Robert Harrison, Oak Ridge National Laboratory
    R. J. Hinde, University of Tennessee
    Guoping Zhang, Indiana State University


    Publications:
    Journal Publications:

    Bai, Yihua and Robert C. Ward: Parallel Block Tridiagonalization of Real Symmetric Matrices, J Parallel Distrib. Comput. 68 (2008) pp. 703-715.

    Bai, Yihua and Robert C. Ward: A Parallel Symmetric Block-Tridiagonal Divide-and-Conquer Algorithm, ACM Trans. Math. Software 33 (2007) Article 25.

    Bai, Yihua, Wilfried N. Gansterer, Robert C. Ward: Block-Tridiagonalization of "Effectively" Sparse Symmetric Matrices, ACM Trans. Math Software 30 (2004) pp. 326-352.

    Gansterer, Wilfried N., Yihua Bai, Robert M. Day and Robert C. Ward: A Framework for Approximating Eigenpairs of Symmetric Block Tridiagonal Matrices, IEEE Computing in Science & Engineering 6 (2004) pp. 50-59.

    Gansterer, Wilfried N., Robert C. Ward, Richard P. Muller and William A. Goddard, III: Computing Approximate Eigenpairs of Symmetric Block Tridiagonal Matrices, SIAM J. Sci. Comput. 25 (2003) pp. 65-85.

    Gansterer, Wilfried N., Robert C. Ward and Richard P. Muller: An Extension of the Divide-and-Conquer Method for a Class of Symmetric Block-Tridiagonal Eigenproblems, ACM Trans. Math. Software 28 (2002) pp. 45-58.

    Others:

    Ward, Robert C. and Yihua Bai: Performance of Parallel Eigensolvers on Electronic Structure Calculations II, Technical Report UT-CS-06-572, University of Tennessee, Knoxville, TN, September 2006.

    Yihua Bai: High Performance Parallel Approximate Eigensolver for Real Symmetric Matrices, PhD Dissertation, University of Tennessee, Knoxville, December 2005.

    Robert C. Ward, Yihua Bai and Justin Pratt: Performance of Parallel Eigensolvers on Electronic Structure Calculations, Technical Report UT-CS-05-560, University of Tennessee, Knoxville, TN, February 2005.

    R. M. Day: A Coarse-Grain Parallel Implementation of the Block Tridiagonal Divide and Conquer Algorithm for Symmetric Eigenproblems, Master Thesis, University of Tennessee, Knoxville, May 2003

    Bai, Y., R. M. Day, W. N. Gansterer and R. C. Ward: New Algorithmic Tools For Electronic Structure Computations, Proceedings of the Fourth IMACS Symposium on Mathematical Modelling, Volume 2 (CD-ROM), Vienna University of Technology (February 2003)



    Partial Research Sponsors:
    The Academic Strategic Alliances Program of the DOE Accelerated Strategic Computing Initiative (ASCI/ASAP) under subcontract to the California Institute of Technology.

    Computing and Computational Sciences Directorate, Oak Ridge National Laboratory

    Science Alliance Program, University of Tennessee


    Contact:
    Dr. Robert C. Ward, ward@eecs.utk.edu