CS 232 Geometric Algorithms: Lecture 1

1. CS 232 Geometric Algorithms: Lecture 1 Shang-Hua Teng Department of Computer Science, Boston University

2. Instructors Main Lectures: Professor Shang-Hua Teng TR 2:00-3:30 PM (COM 213) Sections: TF Scott Russell CAS CS232 A2 648134 Monday 3:00pm-4:00pm in CAS 204A CAS CS32 A3 648147 Tuesday 12-1:00pm in CAS B20

3. Office Hours Professor Shang-Hua Teng Email: steng@cs.bu.eduOffice: MCS-276Office Hours: TR 12:30-2:00pm (or by appointment)Office Phone: 358-2596

4. Office Hours Teaching Fellow: Scott Russell Email: srussell@cs.bu.eduOffice: PSY-223Office Hours: TBA (or by appointment)Office Phone: 3-8921

5. Important Dates: • Due day of each homework • See class webpage • Quiz 1: Tuesday, Feb. 3 (in class) • Midterm:Thursday, Feb. 26 (in class) • Quiz 2: Most likely March 30th (TBA) • Final: to be posted

6. Grading 30% - written assignments10% - quiz 120% - midterm 15% - quiz 225% - final

7. Homework • Write problems in order they are assigned and one problem per page, or just try to separate them clearly so one can see the end of one problem and the beginning of the next one. • The hard-copy (paper) submissions are preferred, so, please send me by email your homework submissions only if you cannot make it to the University on time. But if you do submit electronically: • Make sure to put your name in all electronically submitted files (even if you submit your file by email). • Make sure text file you submit can be printed out and it comes out properly. • Use a format that is well known and easy to open/read (just text format would do it).

8. No late assignments will be accepted. • (Homework Box): If you come to CS building earlier, try submit the hws to the submission box up until 1:45pm. I will be taking the hw's out from the submission box shortly after that time on my way to the class. If you do not make it to the box before 1:45pm, bring the hw to the class. • (Classroom) I will also accept the hw's up until the class start. • I will stop accepting the hw's when the class starts. • If you cannot make it to the class on time, please make sure to submit the hw ahead of time. • The late penalty will be exponential in the minutes it is late (2^m-1, where m is the number of minutes you are late - that's one way to learn about the perils of exponential growth ). The reason the penalty is so steep is that I want to discourage you from finishing at the last minute and coming late to class as the result.

9. Comments from the grader: The main issue is readability, so for example, if you need to draw something, it is better to do it by hand, than to mess with text formatting of drawing pictures in text files. Please, be sure that if you are hand-writing a hw, then your hand-writing is perfectly clear.

10. Policy • Regarding Policy: • If you submit the wrong file or a file with the wrong filename, this includes submission of an empty directory, submission of an executable, etc., then 50% will be taken off from your original grade. Note: In such cases you will be required to show a proof that your source file has a last modification date prior to the submission deadline. Note: attempts to cheat on this will be reported. See Academic Conduct.

11. Policy • If you ask to re-grade your homework please write out the basis of your request. • If the grader finds no basis for your complaint, then 10 points will be taken off your original grade unless the grade is changed. • Note: This is not to say that we discourage you from disputing your grade, but rather we encourage you to read and understand the comments of the grader before complaining.

12. Policy • Under no circumstances should you be copying or using the work of others.It is fine to discuss problems (in general terms) with others, but the specifics of a solution and all of the writing should be done without any collaboration. (See also Academic Conduct)

13. Geometry + Algorithms + Applications • Geometric Concepts • Linear Algebra Representations/Connections • Algorithms

14. Why Geometry? • Useful in many practical applications • Computer Graphics • Imaging Processing • Robotics (path planning) • Network Design • Information Clustering • Engineering and Scientific Simulations • Multi-Variable Optimizations

15. Unstructured Meshes

16. Delaunay Triangulations

17. Why Linear Algebra? • Most natural representations of basic • geometric objects • geometric transformations • Efficient linear algebra algorithms that can be used to solve geometric problems • Language for high-dimensional geometry

18. Why Algorithms? • Algorithm is one of the most important developments in computer science • Geometric and linear algebra algorithms make use of the underlying mathematical structures, • however without efficient algorithms, these mathematical structures may not be useful in computer applications.

19. Books + Notes • The main background text book is • Introduction to Linear Algebra by Gilbert Strang • I will also hand out notes, especially on some geometric algorithms

20. Objectives of This Course • The purpose of this class is to • Learn linear algebra in the context of geometric applications and algorithms • Learn geometric concepts and structures using the language of linear algebra

21. Question • Experience with Matlab? • Experience with other programming languages?