Timothy Rolfe, Ph.D.

Professor of Computer Science
Computer Science Department
Eastern Washington University
319F Computing & Engineering Building
Cheney, WA 99004-2493

Publications area - Programs available - Pictures area - Mandatory mug shot - Resume

E-mail address: RolfeT@ACM.org
Alternatively:     Timothy.Rolfe@ewu.edu

Office telephone: (509) 359-6162

Fall-2009 courses:
    CScD-300, Data Structures
    CScD-320, Algorithms

Other course regularly taught:
    Winter:  CScD-501, Design and Analysis of Algorithms
    Spring:  CScD-543/443, Multiprocessing Programming Environments     

Personal web page:  http://home.earthlink.net/~rolfet/


Picture taken by Judy Hamel 2005 June 11


Degrees

M.S. Computer Science, University of Minnesota, 1989.
Project: "Instructional Package to Animate Various Sorting Algorithms" (Technical Report TR 89-72, Oct 1989)

Ph.D. Theoretical Physical Chemistry, University of Chicago, 1982.
Thesis: "Computer Studies of Molecular Vibrational Behavior"

B.S. Chemistry, Computer Science, and Mathematics, University of Oregon, 1975.

B.A. Scholastic Philosophy, Mount Angel Seminary, 1965.


Research Interests



Other Interests



Recent Publications

"The Assignment Problem:  Exploring Parallelism"
"A Specimen MPI Application: N-Queens in Parallel"
"A cautionary tale:  false efficiencies in the traveling salesman problem"
"Perverse and Foolish Oft I Strayed"
"An Alternative Dynamic Programming Solution for the 0/1 Knapsack"
"Classroom Exercise Demonstrating Linked List Operations"
"Las Vegas Does N-Queens"
"List Processing: Sort Again, Naturally"
"Optimal Queens"
"An Alternative Problem for Backtracking and Bounding"
"Backtracking Algorithms"
"Program Optimization: Enforcement of Local Access, and Array Access via Pointers"
"Spreadsheet-Aided Numerical Experimentation: Analytic Formula for Fibonacci Numbers"
"Bargain-Basement Parallelism"
"One-Time Binary Search Tree Balancing: the Day/Stout/Warren (DSW) Algorithm"
"Distributed Multiprocessor Environments"
"Algorithm Alley: Graph Traversals"
"Binomial Coefficient Recursion: The Good, and The Bad and Ugly"
"Algorithm Alley: AVL Trees"
"Algorithm Alley: Randomized Shuffling"
"Analytic Derivation of Comparisons in Binary Search"
"Particles on a Sphere - A Specimen Multidisciplinary Problem"
"Queens on a Chessboard: Making the Best of a Bad Situation"
"PVM: an affordable parallel processing environment"
"Timing Comparisons of the Householder QR Transformations with Rank-1 and Rank-2 Updates"
"Generation of Permutations with Non-Unique Elements"
"On a Fast Integer Square Root Algorithm"
"Least squares fitting of polynomials and exponentials, with programming examples"

Works in Progress


Links on page numbers connect to PDF files of the articles

"The Assignment Problem:  Exploring Parallelism", inroads (bulletin of the ACM SIG on Computer Science Education), Vol. 41, No. 2 (June 2009), pp. 127-131, by T. J. Rolfe.

"A Specimen MPI Application:  N-Queens in Parallel", inroads (bulletin of the ACM SIG on Computer Science Education), Vol. 40, No. 4 (December 2008), pp. 42-45, by T. J. Rolfe.

"A cautionary tale:  false efficiencies in the traveling salesman problem"  The Journal of Computing Sciences in Colleges, Vol. 24, No. 2 (December 2008), pp. 26-31.  Presented at the 10-11 October 2008 Northwestern Regional Conference of the Consortium for Computing Sciences in Colleges.

"Perverse and Foolish Oft I Strayed", inroads (bulletin of the ACM SIG on Computer Science Education), Vol. 40, No. 2 (June 2008), pp. 52-55, by T. J. Rolfe.

"An Alternative Dynamic Programming Solution for the 0/1 Knapsack" inroads (bulletin of the ACM SIG on Computer Science Education), Vol. 39, No. 4 (December 2007), pp. 54-56.

"Classroom Exercise Demonstrating Linked List Operations", inroads (bulletin of the ACM SIG on Computer Science Education), Vol. 38, No. 4 (December 2006), pp. 83-84.

"Las Vegas Does N-Queens", inroads (bulletin of the ACM SIG on Computer Science Education), Vol. 38, No. 2 (June 2006), pp. 37-38.

"List Processing:  Sort Again, Naturally", inroads (bulletin of the ACM SIG on Computer Science Education), Vol. 37, No. 2 (June 2005), pp. 46-48.

"Optimal Queens", Dr. Dobb’s Journal, Vol. 30, No. 5 (May 2005), pp. 32-37.  Resources associated with this article.  Web copy of the article.

"An Alternative Problem for Backtracking and Bounding", with P.W.Purdom, inroads (bulletin of the ACM SIG on Computer Science Education), Vol. 36, No. 4 (December 2004), pp. 83-84.

"Backtracking Algorithms", Dr. Dobb’s Journal, Vol. 29, No. 5 (May 2004), pp. 48, 50-51.  Reprinted in Developer 2.0, July 2004 [an Indian journal, page reference not available].  Resources associated with this article.   Web copy of the article.

"Program Optimization:  Enforcement of Local Access, and Array Access via Pointers", inroads (bulletin of the ACM SIG on CS Education) Vol. 35 No. 4 ( December 2003), pp. 63-65.

"Spreadsheet-Aided Numerical Experimentation: Analytic Formula for Fibonacci Numbers", inroads (bulletin of the ACM SIG on CS Education) Vol. 35, No. 2 (June 2003), pp. 117-19.

"Bargain-Basement Parallelism", Dr. Dobb’s Journal, Vol. 28, No. 2 (February 2003), pp. 46, 48, 50.  Reprinted in Developer 2.0, April 2003 [an Indian journal, page reference not available].  Resources associated with this article.   Web copy of the article.

"One-Time Binary Search Tree Balancing: the Day/Stout/Warren (DSW) Algorithm", inroads (bulletin of the ACM SIG on Computer Science Education) Vol. 34, No. 4 (December 2002), pp. 85-88.

"Distributed Multiprocessor Environments", The Journal of Computing Sciences in Colleges, Vol. 18, No. 2 (December 2002), pp. 95-104.  Presented at the 4-5 October 2002 Northwestern Regional Conference of the Consortium for Computing Sciences in Colleges.

"Algorithm Alley: Graph Traversals", Dr. Dobb’s Journal, Vol. 27, No. 3 (March 2002), pp, 97-101.  Reprinted in Developer 2.0, May 2002 [an Indian journal, page reference not available].  Resources associated with this article.  Web copy of the article.

"Binomial Coefficient Recursion: The Good, and The Bad and Ugly", inroads (bulletin of the ACM SIG on Computer Science Education) Vol 33, No. 2 (June 2001), pp. 35-36.

"Algorithm Alley: AVL Trees", Dr. Dobb’s Journal, Vol. 25, No. 12 (December 2000), pp. 149-52.  Reprinted in Developer 2.0, July 2001 [an Indian journal, page reference not available].  Resources associated with this article.  Web copy of the article.

"Algorithm Alley: Randomized Shuffling", Dr. Dobb’s Journal, Vol. 25, No. 1 (January 2000), pp. 113-14.  Program associated with this article.  Web copy of the article.

"Analytic Derivation of Comparisons in Binary Search", SIGNUM Newsletter, Vol. 32, No. 4 (October 1997), pp. 15-19.

"Particles on a Sphere - A Specimen Multidisciplinary Problem", presented in the Computer Science Technical Session T21 at the Spring 1996 Small College Computing Symposium at St. Cloud University (St. Cloud, MN), 18-20 April 1996. Published in SCCS Proceedings: 29th Annual Small College Computing Symposium (1996), 456-66.  See below for programs associated with this paper.

"Queens on a Chessboard: Making the Best of a Bad Situation", presented in the Technical Paper Sessions at the Small College Computing Symposium at Augustana College (Sioux Falls, SD) 21-22 Apr 1995. Published in SCCS:  Proceedings of the 28th Annual Small College Computing Symposium (1995), 201-10.  See below for programs associated with this paper.

"PVM: an affordable parallel processing environment" in the Computer Science Education Technical Paper Session T4 at the Small College Computing Symposium at Winona State University (Winona, MN) 29-30 Apr 1994. Published in SCCS Proceedings: 27th Annual Small College Computing Symposium (1994), 118-125.

"Timing Comparisons of the Householder QR Transformations with Rank-1 and Rank-2 Updates", SIGNUM Newsletter, Vol. 25, No. 4 (1990), pp. 19-24.

"Generation of Permutations with Non-Unique Elements", SIGNUM Newsletter, Vol. 23, No. 2 (1988), pp. 24-28.

"On a Fast Integer Square Root Algorithm", SIGNUM Newsletter, Vol. 22, No. 4 (1987), pp. 6-11.

"Least squares fitting of polynomials and exponentials, with programming examples", Mathematics and Computer Education, Vol. 16, No. 2 (Spr, 1982), pp. 122-132, by T. J. Rolfe.  [Ok, it's not recent; but it is my first single-author publication, available thanks to OCR software.]


Works in progress


"The Assignment Problem:  Exploring Parallelism", be prepared for SIGCSE's inroads.  A case study taking two sequential solutions to the linear assignment problem (backtracking and branch-and-bound) and developing parallel implementations.  Because of the 3000 word limitation on inroads articles there are two papers, the first discussing the problem and the backtracking implementations, the second discussing just the branch-and-bound implementation.  The first paper has been published in the June 2009 issue and is shown above.  The second paper has been submitted for the December 2009 issue.  Click here to browse.

"A Specimen of Parallel Programming:  Parallel Merge Sort Implementation", submitted to Dr. Dobb’s Journal.  Transformation of a sequential algorithm (sorting) into a parallel algorithm.  Since Dr. Dobb's is not responding to electronic mail, I need to find another journal.  Click here to browse.

"Iterate Through the Tulips", accepted by Dr. Dobb’s Journal, but then apparently discarded.  This is an exemplification of the use of iterators within Java as compared with explicit manipulations of doubly-linked lists, using sorting algorithms as the basis for discussion.  Click here to browse.

"And the Teacher Shall Be Taught", presently in inroads format — programming anecdote. Click here to browse.


Miscellaneous


Anomalous Vision

Click here to browse.


Programs Available

Small College Computing Symposium 1996 (at St. Cloud State)

Small College Computing Symposium 1995 (at Augustana College)

Animation of Various Sorting Algorithms:


Photography exhibit

In the interests of band-width conservation, this has been moved to a separate file, so that GIFs are only loaded by those interested in them.