as_edge_tbl             Convert network graphs to edge tables as
                        tibbles/data.frames.
classify_options        Classification options for direct, ambigious,
                        and no effect.
nc_estimate_links       Compute model estimates between an external
                        (exposure or outcome) variable and a network.
nc_estimate_network     Create an estimate of the metabolic network as
                        an undirected graph.
nc_standardize          Standardize the metabolic variables.
simulated_data          Simulated dataset with an underlying Directed
                        Graph structure for the metabolites.
