Prof. Tim Davis About me: Background, professional and personal. Horror matrices and other Mathematical poetry Check out The Chapel, led by Richard Parker. The Punkalunk and the Scarydid, a children's story looking for a publisher. Classes: Spring 2012: COT 3100 - Applications of Discrete Structures. Fall 2011: COT 4501 - Numerical Methods. Research: Sparse matrix algorithms The UF Sparse Matrix Collection Summary of available software for sparse direct methods Mathematical Artwork

News, art studios, and popular press:

• The Harvard Advocate, Winter 2011: Blueprint, pages 42 and following.
• Pretty Math Problem, IEEE Spectrum, Oct. 2010.
• FastCoDesign.com: Geeky Science Problems Double as Works of Art
• The most intense moments the universe has ever known are the next 15 seconds, But does it float.com , catalogued under generative art, by Folkert and Atley.
• SIAM News: Sparse Matrix Algorithm Drives SPICE Performance Gains

Contact:

• Tim Davis, Professor, CISE Department. Office E338 CSE. Mailing address: E301 CSE Building, P.O. Box 116120, University of Florida, Gainesville, FL 32611-6120. phone: (352) 505-1546. main dept. phone: (352) 392-1200. fax (352) 392-1220, email: DrTimothyAldenDavis@gmail.com or davis@cise.ufl.edu.

University of Florida Sparse Matrix Collection

MATLAB Primer, 8th edition

MATLAB Primer, 7th edition

Direct Methods for Sparse Linear Systems

Project advisor for Cornerstone Robotics. 1st Place, 2010 TSA Nationals

Current students:

• Sencer Nuri Yeralan, PhD student, Project: graph partitioning, sparse multifrontal QR.
• Sharanyan Chetlur, MS / PhD student, Project: sparse multifrontal QR.

Books:

• Direct Methods for Sparse Linear Systems, T. A. Davis, SIAM, Philadelphia, Sept. 2006. Part of the SIAM Book Series on the Fundamentals of Algorithms. (citations)
• MATLAB Primer, 8th edition T. A. Davis. CRC Press, 2010. (citations)
• MATLAB Primer, 7th edition T. A. Davis and K. Sigmon, CRC Press, 2004.
• MATLAB Primer, 6th edition K. Sigmon and T. A. Davis, CRC Press, 2001.
• On Amazon.com

Recent student theses:

• Efficient Algorithms for Sparse Singular Value Decomposition, Siva Rajamanickam, PhD Thesis, 2009.

Journal articles:

In the pipeline:

• Algorithm 9xx: Reliable Calculation of Numerical Rank, Null Space Bases, Pseudoinverse Solutions and Basic Solutions using SuiteSparseQR Leslie V. Foster and T. A. Davis, submitted to ACM Transactions on Mathematical Software, 2011. Code is incorporated into the latest version of SuiteSparse.
• Algorithm 9xx, FACTORIZE: an object-oriented linear system solver for MATLAB T. A. Davis, submitted to ACM Transactions on Mathematical Software, 2011. Code is incorporated into the latest version of SuiteSparse.

In print:

• The University of Florida Sparse Matrix Collection T. A. Davis and Y. F. Hu, Vol 38, number 1, ACM Transactions on Mathematical Software, 2011. (as tech report) (citations)
• Algorithm 915: SuiteSparseQR: Multifrontal multithreaded rank-revealing sparse QR factorization, T. A. Davis, Vol 38, number 1, ACM Transactions on Mathematical Software, 2011. (as tech report) (citations)
• Hypergraph-based unsymmetric nested dissection ordering for sparse LU factorization L. Grigori, E. Boman, S. Donfack, and T. A. Davis, SIAM Journal on Scientific Computing, vol 32, no 6, pp 3426-3446, 2010. (as tech report) (citations)
• Algorithm 907: KLU, a direct sparse solver for circuit simulation problems T. A. Davis and E. Palamadai Natarajan, ACM Transactions on Mathematical Software, vol 37, no. 3, 2010. (citations)
• Dynamic supernodes in sparse Cholesky update/downdate and triangular solves, T. A. Davis and W. W. Hager, ACM Trans. Math. Software, Vol 35, No. 4, 2009. (as CISE Tech Report) (citations)
• Algorithm 887: CHOLMOD, supernodal sparse Cholesky factorization and update/downdate , Y. Chen, T. A. Davis, W. W. Hager, and S. Rajamanickam, ACM Trans. Math. Software, Vol 35, No. 3, 2009. (as CISE Tech Report) (citations)
• Dual multilevel optimization, T. A. Davis and W. W. Hager, Mathematical Programming, Vol 112, No. 2, April 2008, pp. 403-425. (also as tech report) (as CISE Tech Report) (citations)
• A sparse proximal implementation of the LP Dual Active Set Algorithm, T. A. Davis and W. W. Hager, Mathematical Programming, Vol 112, No. 2, April 2008, pp. 275-301. (also as tech report). (as CISE Tech Report) (citations)
• Algorithm 849: A concise sparse Cholesky factorization package, T. A. Davis, ACM Transactions on Mathematical Software, vol 31, no. 4, Dec. 2005, pp. 587-591. (as CISE Tech Report) (citations)
• Model representation with aesthetic computing: method and empirical study, P. Fishwick, J. Douglas, and T. A. Davis, ACM Transactions on Modeling and Computer Simulation, vol 15, no 3, July 2005, pp. 254-279. (citations)
• Row modifications of a sparse Cholesky factorization, T. A. Davis and W. W. Hager, SIAM Journal on Matrix Analysis and Applications, vol 26, no 3, pp. 621-639, 2005. (as CISE Tech Report) (citations)
• A column approximate minimum degree ordering algorithm, T. A. Davis, J. R. Gilbert, S. Larimore, E. Ng, ACM Transactions on Mathematical Software, vol 30, no. 3, Sept. 2004, pp. 353-376. (as CISE Tech Report) (citations)
• Algorithm 836: COLAMD, a column approximate minimum degree ordering algorithm T. A. Davis, J. R. Gilbert, S. Larimore, E. Ng, ACM Transactions on Mathematical Software, vol 30, no. 3, Sept. 2004, pp. 377-380. (as CISE Tech Report) (citations)
• Algorithm 837: AMD, An approximate minimum degree ordering algorithm, P. Amestoy, T. A. Davis, and I. S. Duff, ACM Transactions on Mathematical Software, vol 30, no. 3, Sept. 2004, pp. 381-388. (as CISE Tech Report) (citations)
• A column pre-ordering strategy for the unsymmetric-pattern multifrontal method, T. A. Davis, ACM Transactions on Mathematical Software, vol 30, no. 2, June 2004, pp. 165-195. (as CISE Tech Report) (citations)
• Algorithm 832: UMFPACK, an unsymmetric-pattern multifrontal method, T. A. Davis, ACM Transactions on Mathematical Software, vol 30, no. 2, June 2004, pp. 196-199. (as CISE Tech Report) (citations)
• Multiple-rank modifications of a sparse Cholesky factorization, T. A. Davis and W. W. Hager, SIAM Journal on Matrix Analysis and Applications, vol. 22, no. 4, pp. 997-1013, 2001. (as CISE Tech Report) (citations)
• Modifying a sparse Cholesky factorization, T. A. Davis and W. W. Hager, SIAM Journal on Matrix Analysis and Applications, vol. 20, no. 3, pp. 606-627, 1999. (as CISE Tech Report) (citations)
• A combined unifrontal/multifrontal method for unsymmetric sparse matrices, T. A. Davis and I. S. Duff, ACM Transactions on Mathematical Software, vol. 25, no. 1, pp. 1-19, March 1999. (as CISE Tech Report) (citations)
• An unsymmetric-pattern multifrontal method for sparse LU factorization, T. A. Davis and I. S. Duff, SIAM Journal on Matrix Analysis and Applications, vol 18, no. 1, pp. 140-158, Jan. 1997. (as CISE Tech Report) (citations)
• An approximate minimum degree ordering algorithm, P. Amestoy, T. A. Davis, and I. S. Duff, SIAM Journal on Matrix Analysis and Applications, vol 17, no. 4, pp. 886-905, Dec. 1996. (as CISE Tech Report) (citations)
• A concurrent dynamic task graph, T. Johnson, T. A. Davis, and S. M. Hadfield, Parallel Computing, vol. 22, no. 2, pp. 327-333, Feb. 1996. (citations)
• Multifrontal vs. frontal techniques for chemical process simulation on supercomputers, S. E. Zitney, J. Mallya, T. A. Davis, and M. A. Stadtherr, J. Computers and Chemical Engineering, vol 20, No 6/7, pp. 641-646, 1996. (as CISE Tech Report) (citations)
• The use of graph theory in a parallel multifrontal method for sequences of unsymmetric pattern sparse matrices, S. M. Hadfield and T. A. Davis, Congressus Numerantium, vol. 108, pp. 43-52, 1995. (as CISE Tech Report) (citations)
• Parallel buddy memory management, T. Johnson and T. A. Davis, Parallel Processing Letters, vol. 2, no. 4, pp. 391-398, 1992. (as CISE Tech Report) (citations)
• A nondeterministic parallel algorithm for general unsymmetric sparse LU factorization, T. A. Davis and P.-C. Yew, SIAM Journal on Matrix Analysis and Applications, vol. 11, no. 3, pp. 383-402, 1990. (citations)
• Pairwise reduction for the direct, parallel solution of sparse unsymmetric sets of linear equations, T. A. Davis and E. S. Davidson, IEEE Transactions on Computers, vol. 37, no. 12, pp. 1648-1654, 1988. (citations)

Other articles, talks, and miscellaneous publications

• Sparse matrix methods for circuit simulation problems, SCEE 2010 (Scientific Computing in Electrical Engineering), invited speaker, Toulouse, France, Sept. 2010.
• Multifrontal multithreaded rank-revealing sparse QR factorization, Dagstuhl Seminar on Combinatorial Scientific Computing, Feb. 2009.
• Direct Methods for Sparse Linear Systems: the MATLAB sparse backslash, an invited Plenary Talk at the SIAM Annual Meeting, Boston, 2006.
• Dynamic supernodes in sparse Cholesky update/downdate for active set methods, SIAM 2008 Annual Meeting, San Diego, CA.
• Sparse matrix research and software development at the University of Florida, SIAM 2008 Annual Meeting, San Diego, CA.
• Creating sparse finite-element matrices in MATLAB, guest blog in Loren on the Art of MATLAB, March 1st, 2007, http://blogs.mathworks.com/loren/.
• KLU: a "Clark Kent" sparse LU factorization algorithm for circuit matrices, a talk given by Ken Stanley at the 2004 SIAM Conference on Parallel Processing for Scientific Computing (PP04).
• Block Exchange in Graph Partitioning, in Approximation and Complexity in Numerical Optimization: Continuous and Discrete Problems, P. M. Pardalos, Editor, 1999, Kluwer, pp. 299-307.
• CISE Technical reports. You can see a complete list of my technical reports by searching by author.
• Quadratic programming techniques in graph partitioning, S. C. Park, T. A. Davis, W. W. Hager, H. Zhang, CISE Tech Report