(self, rank, superset)
return Subset.subset_from_bitlist(superset, graycode_bitlist)
Gets the Gray code ordered subset of the specified rank.

        Examples
        ========

        >>> from sympy.combinatorics.subsets import Subset
        >>> Subset.unrank_gray(4, ['a','b','c']).subset
        ['a', 'b']
        >>> Subset.unrank_gray(0, ['a','b','c']).subset
        []

        See Also
        ========
        iterate_graycode, rank_gray
Gets the Gray code ordered subset of the specified rank.
Gets the Gray code ordered subset of the specified rank .
def unrank_gray(self, rank, superset):
        """
        Gets the Gray code ordered subset of the specified rank.

        Examples
        ========

        >>> from sympy.combinatorics.subsets import Subset
        >>> Subset.unrank_gray(4, ['a','b','c']).subset
        ['a', 'b']
        >>> Subset.unrank_gray(0, ['a','b','c']).subset
        []

        See Also
        ========
        iterate_graycode, rank_gray
        """
        graycode_bitlist = GrayCode.unrank(len(superset), rank)
        return Subset.subset_from_bitlist(superset, graycode_bitlist)
def unrank_gray ( self , rank , superset ) : graycode_bitlist = GrayCode . unrank ( len ( superset ) , rank ) return Subset . subset_from_bitlist ( superset , graycode_bitlist )