layout_fixed_coords: Layout with fixed coordinates

Description

force-directed graph layout based on stress majorization with fixed coordinates for some nodes

Usage

layout_with_fixed_coords(
  g,
  coords,
  weights = NA,
  iter = 500,
  tol = 1e-04,
  mds = TRUE,
  bbox = 30
)
layout_igraph_fixed_coords(
  g,
  coords,
  weights = NA,
  iter = 500,
  tol = 1e-04,
  mds = TRUE,
  bbox = 30,
  circular
)

Value

matrix of xy coordinates

Arguments

g: igraph object
coords: numeric n x 2 matrix, where n is the number of nodes. values are either NA or fixed coordinates. coordinates are only calculated for the NA values.
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: constrain dimension of output. 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.

Examples

Run this code

library(igraph)
set.seed(12)
g <- sample_bipartite(10, 5, "gnp", 0.5)
fxy <- cbind(c(rep(0, 10), rep(1, 5)), NA)
xy <- layout_with_fixed_coords(g, fxy)