R/helpers.R

In LSTbook: Data and Software for "Lessons in Statistical Thinking"

#' helper functions for transforming and checking DAGs
#' Made obsolete with switch to datasim
# dag_to_igraph <- function(DAG, show_hidden=FALSE) {
#   nnames <- node_names(DAG)
#   # Get rid of the hidden ones
#   if (!show_hidden) nnames[grepl("^\\.", nnames)] <- " "
#
#   edges <- numeric(0)
#   for (k in 1:length(DAG)) {
#     # loop over all the nodes
#     if (!show_hidden) {
#       this_name <- all.names(DAG[[k]][[2]])
#       if (grepl("^\\.", this_name)) next;
#     }
#     from_names <- all.names(DAG[[k]][[3]])
#     from_nums <- which(nnames %in% from_names)
#     if (length(from_nums) > 0 ) {
#       new_edges <- c(rbind(rbind(from_nums), k))
#       edges <- c(edges, new_edges)
#     }
#
#   }
#
#   g <- igraph::make_empty_graph(n=length(nnames), directed=TRUE) %>%
#     igraph::add_edges(edges) %>%
#     igraph::set_vertex_attr("label", value=nnames)
#
#
#   g
# }
#
# dag_sort <- function(DAG) {
#   new_order <- dag_to_igraph(DAG) %>% igraph::topo_sort()
#
#   res <- DAG[new_order]
#   class(res) <- c("dagsystem")
#
#   res
# }
#
# node_names <- function(DAG) {
#   res <- unlist(
#     lapply(DAG, function(x) all.vars(x[[2]]))
#   )
#   if (length(unique(res)) != length(res))
#     stop("Duplicate name in DAG")
#   res
# }
#
# source_nodes <- function(DAG) {
#   input_names <- unlist(
#     lapply(DAG, function(x) all.vars(x[[3]]))
#   )
#
#   unique(input_names)
# }
#
# # make sure all nodes used on the right side of formulas
# # appear on the left-hand side of one of the formulas.
# dag_check <- function(DAG) {
#   all(source_nodes(DAG) %in% node_names(DAG))
#   TRUE
# }
#