def __iter__(self): """ An iterator for the standard ribbon of ``self``. EXAMPLES:: sage: [t for t in StandardRibbonShapedTableaux([2,2])] [[[None, 2, 4], [1, 3]], [[None, 2, 3], [1, 4]], [[None, 1, 4], [2, 3]], [[None, 1, 3], [2, 4]], [[None, 1, 2], [3, 4]]] """ for p in descents_composition_list(self.shape): yield self.from_permutation(p)
def __iter__(self): """ An iterator for the standard ribbon of ribbon shape shape. EXAMPLES:: sage: [t for t in StandardRibbons([2,2])] [[[2, 4], [1, 3]], [[2, 3], [1, 4]], [[1, 4], [2, 3]], [[1, 3], [2, 4]], [[1, 2], [3, 4]]] """ for p in permutation.descents_composition_list(self.shape): yield from_permutation(p)