R/as.igraph.R

In rmangal: 'Mangal' Client

#' Coerce `mgNetworksCollection` or `mgNetwork` objects to `igraph` objects.
#'
#' @param x either a `mgNetworksCollection` or a `mgNetwork` object.
#' @param ... currently ignored.
#'
#' @return
#' An object of class `igraph` for a `mgNetwork` object and a list of
#' `igraph` objects for `mgNetworksCollection`.
#'
#' @importFrom igraph as.igraph
#' @describeIn as.igraph Convert `mgNetwork` objects to `igraph` objects.
#' @export
as.igraph.mgNetwork <- function(x, ...) {
  # Simple test to know if the graph is directed or undirected
  directed <- ifelse(all(x$interactions$direction == "directed"), TRUE, FALSE)
  # Move id edge to the last column
  x$interactions <- as.data.frame(x$interactions, stringsAsFactors = FALSE)
  # drop geometry
  x$interactions <- x$interactions[, names(x$interactions) != "geom"]
  nm <- c("node_from", "node_to")
  x$interactions <- x$interactions[
    ,
    c(nm, names(x$interactions)[!names(x$interactions) %in% nm])
  ]
  igraph::graph_from_data_frame(
    d = x$interactions, directed = directed,
    vertices = x$nodes
  )
}

#' @describeIn as.igraph
#' Convert `mgNetworksCollection` objects to a list of `igraph` objects.
#' @export
as.igraph.mgNetworksCollection <- function(x, ...) {
  lapply(x, as.igraph.mgNetwork)
}

#' @export
igraph::as.igraph