## CombinatorialIteration

CombinatorialIteration
is a package for generating combinatorial objects including
partitions, permutations, subsets, and standard tableaux.
Objects are generated one by one: enter in an object to get the next one.

The primary purpose is to traverse a list of
partitions, permutations, subsets, or tableaux
without generating and storing the full list.
This arises in, for example, sums indexed by partitions;
iteration allows one to compute the terms of the sum one-by-one
by initializing a variable with the first partition
and repeatedly (with a for loop) iterating
the 'next' function to visit all of the partitions
exactly once each.

One may also go backward with 'prev[ious]' functions,
reversing the order of traversal of the 'next' functions.

See:
Nijenhuis, Albert; Wilf, Herbert S. *Combinatorial algorithms.*
Second edition. 1978.

You may download the package.
To install it, after downloading, run Macaulay2 in a directory containing the downloaded file
and issue the Macaulay2 command `installPackage("CombinatorialIteration")`

.

*
zteitler@boisestate.edu
*

Back to main page