// Returns true if at least one face matches the facesel rule but all of them public bool FaceSelectionIsValid(ConwayPoly.FaceSelections facesel) { if (ConwayOperators.Count == 0 && PolyType > 0) { _conwayPoly = new ConwayPoly(WythoffPoly); // We need a conway poly } int includedFaceCount = Enumerable.Range(0, _conwayPoly.Faces.Count).Count(x => _conwayPoly.IncludeFace(x, facesel)); return(includedFaceCount > 0 && includedFaceCount < _conwayPoly.Faces.Count); }