The sparta package implements new methods (multiplication, marginalization etc.) for dealing with conditional probability tables (CPTs) and are especially useful when the CPTs are sparse.
The jti, https://github.com/mlindsk/jti, package (on CRAN) implements belief propagation via the Junction Tree Algorithm which relies heavily on sparta tables. See also https://github.com/mlindsk/pednoa for a usecase of jti where “ordinary/dense” table operations will fail.