Formulas in netplot — netplot-formulae • netplot

Edge colors in both nplot() and set_edge_gpar() can be specified using a formula based on ego() and alter() (source and target). This way the user can set various types of combination varying the mixing of the colors, the alpha levels, and the actual mixing colors to create edge colors.

color_formula(x, col, alpha, env, type, mix = 1, postfix = NULL)

ego(...)

alter(...)

Arguments

x	An object of class netplot.
col	Any valid color. Can be a single color or a vector.
alpha	Number. Alpha levels
env, type, postfix	For internal use only.
mix	Number. For mixing colors between `ego` and `alter`
...	Passed to `color_formula`.

Value

Nothing. These functions are called internally when using formulas. color_formula modifies the environment env.

Examples

if (require(gridExtra) & require(magrittr)) {
  library(igraph)
  net <- make_ring(4)

  set.seed(1)
  np <- nplot(net, vertex.color = grDevices::hcl.colors(4), vertex.size.range=c(.1, .1))
  np %<>% set_edge_gpar(lwd = 4)

  grid.arrange(
    np,
    np %>% set_edge_gpar(col =~ego + alter),
    np %>% set_edge_gpar(col =~ego(alpha=0) + alter),
    np %>% set_edge_gpar(col =~ego + alter(alpha=0)),
    np %>% set_edge_gpar(col =~ego(mix=0) + alter(mix=1)),
    np %>% set_edge_gpar(col =~ego(mix=1) + alter(mix=0))
  )
}
#> Loading required package: gridExtra