graphlayouts (version 1.2.2)

layout_stress: stress majorization layout

Description

force-directed graph layout based on stress majorization. Similar to Kamada-Kawai, but generally faster and with better results.

Usage

layout_with_stress(
  g,
  weights = NA,
  iter = 500,
  tol = 1e-04,
  mds = TRUE,
  bbox = 30
)
layout_igraph_stress(
  g,
  weights = NA,
  iter = 500,
  tol = 1e-04,
  mds = TRUE,
  bbox = 30,
  circular
)

Value

matrix of xy coordinates

Arguments

g

igraph object

weights

possibly a numeric vector with edge weights. If this is NULL and the graph has a weight edge attribute, then the attribute is used. If this is NA then no weights are used (even if the graph has a weight attribute). By default, weights are ignored. See details for more.

iter

number of iterations during stress optimization

tol

stopping criterion for stress optimization

mds

should an MDS layout be used as initial layout (default: TRUE)

bbox

width of layout. Only relevant to determine the placement of disconnected graphs

circular

not used

Details

Be careful when using weights. In most cases, the inverse of the edge weights should be used to ensure that the endpoints of an edges with higher weights are closer together (weights=1/E(g)$weight).

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

Gansner, E. R., Koren, Y., & North, S. (2004). Graph drawing by stress majorization. In International Symposium on Graph Drawing (pp. 239-250). Springer, Berlin, Heidelberg.

See Also

layout_stress3D

Examples

library(igraph)
set.seed(665)

g <- sample_pa(100, 1, 1, directed = FALSE)

# calculate layout manually
xy <- layout_with_stress(g)

# use it with ggraph
if (FALSE) {
library(ggraph)
ggraph(g, layout = "stress") +
    geom_edge_link0(edge_width = 0.2, colour = "grey") +
    geom_node_point(col = "black", size = 0.3) +
    theme_graph()
}