R/util.R

In tzimiskes/causality: Examine The Causal Structure of Data

# get the skeleton from the edge representation
# loop over the nodes
.calculate_adjacencies <- function(edges, nodes)
{
    n.edges <- nrow(edges)
    adjacencies <- lapply(nodes, function(node) {
        neighborhood <- c()
        # loop over the edges
        for (i in 1:n.edges) {
            # if a node is in an edge, find its partner (neighbor)
            if( node %in% edges[i, 1:2]) {
                neighbor <- edges[i, c(node != edges[i, 1:2], F)]
                if (!(neighbor %in% neighborhood))
                    neighborhood <- c(neighborhood, neighbor)
            }
        }
        return(neighborhood)
    })
    names(adjacencies) <- nodes
    return(adjacencies)
}