R/extend_network.R

In EGAD: Extending guilt by association by degree

#' Builds an extended network from a binary network
#'
#' The function extends a binary network by using the inverse
#' of the path length between nodes as a weighted edge
#'
#' @param net matrix binary and symmetric 
#' @param max numeric maximum number of jumps
#'
#' @return ext_net matrix dense and symmetric
#'
#' 
#' @keywords extended network
#' igraph
#' shortest path length
#'
#' @examples
#' net <- matrix( sample(c(0,1),36, replace=TRUE), nrow=6,byrow=TRUE)
#' ext_net <- extend_network(net)
#'
#' 
#' @importFrom igraph graph.adjacency shortest.paths
#' @export
#'   

extend_network <- function(net, max = 6) {
    g <- igraph::graph.adjacency(net, mode = "undirected")
    s <- igraph::shortest.paths(g)
    s[s > max] <- NA
    s[!is.finite(s)] <- NA
    ext_net <- 1/s
    diag(ext_net) <- 1
    return(ext_net)
}