arrange nodes in concentric circles around a focal node according to their distance from the focus.

layout_with_focus(g, v, weights = NA, iter = 500, tol = 1e-04)

layout_igraph_focus(g, v, weights = NA, iter = 500, tol = 1e-04, circular)

Arguments

g

igraph object

v

id of focal node to be placed in the center

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

circular

not used

Value

a list containing xy coordinates and the distances to the focal node

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

Brandes, U., & Pich, C. (2011). More flexible radial layout. Journal of Graph Algorithms and Applications, 15(1), 157-173.

Examples

library(igraph) library(ggraph) g <- sample_gnp(10,0.4) coords <- layout_with_focus(g,v = 1)
#> Error in layout_with_focus(g, v = 1): g must be a connected graph.
coords
#> Error in eval(expr, envir, enclos): object 'coords' not found