layout_stress: stress majorization layout

In graphlayouts: Additional Layout Algorithms for Network Visualizations

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
)

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.

Value

matrix of xy coordinates

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
## Not run: 
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()

## End(Not run)

graphlayouts documentation built on Sept. 30, 2024, 9:22 a.m.