Elsevier Science Home
Computer Physics Communications Program Library
Full text online from Science Direct
Programs in Physics & Physical Chemistry
CPC Home

[Licence| Download | New Version Template] aamj_v1_0.gz(5 Kbytes)
Manuscript Title: Computation of outer products of Schur functions.
Authors: O. Egecioglu
Program title: SCHUR
Catalogue identifier: AAMJ_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 28(1982)183
Programming language: Pascal.
Computer: PDP-11/780.
Operating system: USCD PASCAL SYSTEM.
RAM: 2K words
Word size: 16
Peripherals: disc.
Keywords: General purpose, Algebras, Schur function, Outer product, Irreducible Representation, Partition, Ferrers' diagram, Standard tableau, Skew-tableau, Backtracking, Depth-first order, Balanced tree.
Classification: 4.2.

Nature of problem:
To express the (outer) product of an arbitrary number of Schur functions as a linear combination of Schur functions.

Solution method:
A new backtracking algorithm is implemented to generate the partitions that appear in the expansion of a product of Schur functions.

The size of the problem that can be handled by the implementation is restricted by the total number of parts of the input partitions (no more than 255).

Unusual features:
The partitions generated by the algorithm are maintained as nodes of a balanced binary tree to minimize list insertion time.

Running time:
{5**2}{3**2 2} 2 s.
{31}{2**2}{21}{1**2} 8 s.
(Time indicated includes the disk-write time : 1 and 2 s, respectively.)