orbit
orbit
The library came out from the observation that most problems in computational abstract algebra require a search algorithm. Instead of writing them again and again, it is natural to abstract the search part out. It is used by KIGEN.
This library contains generic search algorithms. A set-valued operator and predicates for recognizing possible and actual solutions need to be given.
The abstraction overhead is counterbalanced by parallel execution (using the reducers library).
Orbit computation example
For computing al subsets of a set, we define the following set-valued function.
(defn subset-covers
"All covering (missing a single element only) subsets of a collection.
The collection is assumed to be a set."
[coll]
(map (fn [x]
(remove (partial = x) coll))
coll))
Then we can call a full-orbit function by giving the seeds (a 4-element set in this case) to calculate all subsets.
(orbit.core/full-orbit [(range 4)] subset-covers)
#{(0 1 3) (2 3) (0 2 3) (0 1 2) () (3) (1 3) (0) (0 3) (1 2 3) (0 2) (2) (1 2) (1) (0 1 2 3) (0 1)}