Dear William, If you use DoubleCoset(H,One(H),K) creation is very cheap and membership tests reasonable (they use a decomposition as union of right cosets). You also could get elements if you really wanted. However if you do other set operations (union, intersection etc.) iGAP likely will unpack to a list.
Best, Alexander Hulpke -- Colorado State University, Department of Mathematics, Weber Building, 1874 Campus Delivery, Fort Collins, CO 80523-1874, USA email: hul...@math.colostate.edu, Phone: ++1-970-4914288 http://www.math.colostate.edu/~hulpke _______________________________________________ Forum mailing list Forum@mail.gap-system.org http://mail.gap-system.org/mailman/listinfo/forum
