Rechenkurs GAP (Wintersemester 2014/2015)

• Veranstalter: Prof. Dr. Max Horn
• Termin Übung: Jeden Donnerstag 10:00 - 12:00 Uhr in PC-Labor des Mathematischen Instituts

News

2015-10-09

Update for sheet 2: explain how "for"-loops in GAP work in more detail

2015-09-14

Some cosmetic revisions

2014-11-06

Add the "bad locals" example

2014-11-05

Uploaded slightly revised versions of worksheets 3 and 4

Worksheets

• sheet0-install.pdf
• sheet1-basics.pdf
• sheet2-linAlg.pdf
• sheet3-functional.pdf
• sheet4-perms.pdf
• sheet5-misc.pdf
• sheet6-groups.pdf
• sheet7.pdf

Bonus problems

Sieve (deadline 20. November 2014)

Write a function Sieve(n) which takes a positive integer n, and returns a list containing all primes less or equal n, in strictly ascending order. Compute this list using the sieve of Eratosthenes. Submit your solution in a file called sieve.g.

Your program should be able to compute Sieve(10^7) in under 20 seconds.

Hint: You can use the function RootInt to compute an integer approximation of the square root of an integer (consult the manual to learn how to use it). However, it is also fine to write a solution working without it.

Hint: The function Add may also be useful: It can append a single element to the end of a list (again, please consult the GAP manual for details).

Miscellaneous

The perils of not using local properly