Function Repository Resource:

NthGrayCodeSubset

Get the n-th Gray code subset of a list

Contributed by: Wolfram Staff (original content by Sriram V. Pemmaraju and Steven S. Skiena)

ResourceFunction["NthGrayCodeSubset"][n,list]

gives the n^th subset of list, listed in Gray code order.

Details and Options

In Gray code order, subsets differ from its neighbors by the insertion or deletion of one element.

In ResourceFunction["NthGrayCodeSubset"][…], the empty set is indexed as set 0.

ResourceFunction["NthGrayCodeSubset"] extracts parts cyclically from a List of all possible subsets.

Fifth subset of a List in Gray code order:

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In Gray code order, subsets differ from their neighbors by by the insertion or deletion of exactly one element:

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Sequentially reconstruct the subset list with NthGrayCodeSubset:

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The resource function GrayCodeSubsetIndex gives back the index n of the subset constructed with NthGrayCodeSubset:

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