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Allow the computation of orbits on tuples and sets #13879

Open ca0b67cc-9d10-44c6-be51-5d9e2cdee96a opened 11 years ago

ca0b67cc-9d10-44c6-be51-5d9e2cdee96a commented 11 years ago

It is often useful to consider the group action of a permutation group G acting in the natural way on sets and tuples of the original point set.

For example we need this thing in the graph theory module for testing edge/arc-transitivity of graphs (#13721). Since there is currently no way to do this directly in sage we use a (ugly) hack and call gap directly as

gap("OrbitLength("+str(A._gap_())+"," + str(e) + ",OnTuples);")

it would be nice if somehow we could implement the Orbit and Orbits method of permutation groups to handle these actions as well.

I believe the patch to be quite simple but would like to hear what you guys think and suggest before considering to implement it myself.

CC: @sagetrac-azi @nathanncohen

Component: group theory

Issue created by migration from https://trac.sagemath.org/ticket/13879

6bdad4c1-1e26-4f2f-a442-a01a2292c181 commented 11 years ago

Description changed:

--- 
+++ 
@@ -1,6 +1,6 @@
 It is often useful to consider the group action of a permutation group G acting in the natural way on sets and tuples of the original point set. 

-For example we need this thing in the graph theory module for testing edge/arc-transitivity of graphs. Since there is currently no way to do this directly in sage we use a (ugly) hack and call gap directly as
+For example we need this thing in the graph theory module for testing edge/arc-transitivity of graphs (#13721). Since there is currently no way to do this directly in sage we use a (ugly) hack and call gap directly as

gap("OrbitLength("+str(A.gap())+"," + str(e) + ",OnTuples);")