backbone graph layout — layout_backbone • graphlayouts

emphasizes a hidden group structure if it exists in the graph. Calculates a layout for a sparsified network only including the most embedded edges. Deleted edges are added back after the layout is calculated.

Usage

layout_as_backbone(g, keep = 0.2, backbone = TRUE)

layout_igraph_backbone(g, keep = 0.2, backbone = TRUE, circular)

Arguments

g: igraph object
keep: fraction of edges to keep during backbone calculation
backbone: logical. Return edge ids of the backbone (Default: TRUE)
circular: not used

Value

list of xy coordinates and vector of edge ids included in the backbone

Details

The layout_igraph_* function should not be used directly. It is only used as an argument for plotting with 'igraph'. 'ggraph' natively supports the layout.

References

Nocaj, A., Ortmann, M., & Brandes, U. (2015). Untangling the hairballs of multi-centered, small-world online social media networks. Journal of Graph Algorithms and Applications: JGAA, 19(2), 595-618.

Examples

library(igraph)

g <- sample_islands(9, 20, 0.4, 9)
g <- simplify(g)
V(g)$grp <- as.character(rep(1:9, each = 20))
bb <- layout_as_backbone(g, keep = 0.4)

# add backbone links as edge attribute
E(g)$col <- FALSE
E(g)$col[bb$backbone] <- TRUE