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Plot Community Graphs

Source: R/pald_functions.R
plot_community_graphs.Rd

Provides a plot of the community graphs, with connected components of the graph of strong ties colored by connected component.

Usage

plot_community_graphs(
  c,
  show_labels = TRUE,
  only_strong = FALSE,
  emph_strong = 2,
  edge_width_factor = 50,
  colors = NULL,
  ...
)

Arguments

c

A cohesion_matrix object, a matrix of cohesion values (see cohesion_matrix).

show_labels

Set to FALSE to omit vertex labels (to display a subset of labels, use optional parameter vertex.label to modify the label list). Default: TRUE.

only_strong

Set to TRUE if only strong ties, G_strong, should be displayed; the default FALSE will show both strong (colored by connected component) and weak ties (in gray).

emph_strong

Numeric. The numeric factor by which the edge widths of strong ties are emphasized in the display; the default is 2.

edge_width_factor

Numeric. Modify to change displayed edge widths. Default: 50.

colors

A vector of display colors, if none is given a default list (of length 24) is provided.

...

Optional parameters to pass to the igraph::plot.igraph. function. Some commonly passed arguments include:

  • layout A layout for the graph. If none is specified, FR-graph drawing algorithm is used.

  • vertex.label A vector containing label names. If none is given, the rownames of c are used

  • vertex.size A numeric value for vertex size (default = 1)

  • vertex.color.vec A vector of color names for coloring the vertices

  • vertex.label.cex A numeric value for modifying the vertex label size. (default = 1)

Value

A plot of the community graphs.

Details

Plots the community graph, G, with the sub-graph of strong ties emphasized and colored by connected component. If no layout is provided, the Fruchterman-Reingold (FR) graph drawing algorithm is used. Note that the FR graph drawing algorithm may provide a somewhat different layout each time it is run. You can also access and save a given graph layout using community_graphs(C)$layout. The example below shows how to display only a subset of vertex labels.

Note that the parameter emph_strong is for visualization purposes only and does not influence the network layout.

Examples

C <- cohesion_matrix(dist(exdata1))
plot_community_graphs(C, emph_strong = 1, layout = as.matrix(exdata1))

plot_community_graphs(C, only_strong = TRUE)


C2 <- cohesion_matrix(cognate_dist)
subset_lang_names <- rownames(C2)
subset_lang_names[sample(1:87, 60)] <- ""
plot_community_graphs(C2, vertex.label = subset_lang_names, vertex.size = 3)