Geek asks and answers

Draw multiple discrete networks in R using igraph

I have a simple set of directional relationships (parent-> child) that I want to draw. My data is structured in such a way that there are many discrete subnets. Here are some fake data similar to mine.

require(igraph)
parents<-c("A","A","C","C","F","F","H","I")
children<-c("B","C","D","E","G","H","I","J")
begats<-data.frame(parents=parents,children=children)
graph_begats<-graph.data.frame(begats)
plot(graph_begats)

There are two different subnets in fake data, each of which is a strictly parent parent. I need to draw lines as tree networks in the same window (ideally in the same vertex coordinate system). I tried using layout.reingold.tilford (), but at best, all I can do is one of the trees, all the other vertices built on top of the root vertex, like this.

lo<-layout.reingold.tilford(graph_begats,root=1)
plot(graph_begats,layout=lo)

Any ideas for this for an arbitrary number of discrete lines?

+5
source
1

, , . , . . node .

require(igraph)

## Some data
parents <- c("A", "A", "C", "C", "F", "F", "H", "I")
children <- c("B", "C", "D", "E", "G", "H", "I", "J")
begats <- data.frame(parents=parents, children=children)
graph_begats <- graph.data.frame(begats)

## Decompose the graph, individual layouts
comp <- decompose.graph(graph_begats)
roots <- sapply(lapply(comp, topological.sort), head, n=1)
coords <- mapply(FUN=layout.reingold.tilford, comp,
                 root=roots, SIMPLIFY=FALSE)

## Put the graphs side by side, roots on the top
width <- sapply(coords, function(x) { r <- range(x[, 1]); r[2] - r[1] })
gap <- 0.5
shift <- c(0, cumsum(width[-length(width)] + gap))
ncoords <- mapply(FUN=function(mat, shift) {
  mat[,1] <- mat[,1] - min(mat[,1]) + shift
  mat[,2] <- mat[,2] - max(mat[,2])
  mat
}, coords, shift, SIMPLIFY=FALSE)

## Put together the coordinates for the original graph,
## based on the names of the vertices
lay <- matrix(0, ncol=2, nrow=vcount(graph_begats))
for (i in seq_along(comp)) {
  lay[match(V(comp[[i]])$name, V(graph_begats)$name),] <- ncoords[[i]]
}

## Plot everything
par(mar=c(0,0,0,0))
plot(graph_begats, layout=lay)

plot

+6

More articles:


All Articles