as.matrix with a bipartite network object does not return a matrix

[leifeld]

See here for a case where a bipartite network object with a single second-mode node cannot be converted to a matrix using as.matrix. Not sure if that's related to #64, but perhaps worth addressing together?

[leifeld]

For completeness, a self-contained and replicable version of the example the user provided:

library("dplyr")
library("network")

node_vars <- data.frame(
  name = c("Actor 1", "Actor 1", "Actor 2", "Actor 2", "Actor 3", "Actor 3"),
  var1 = c("A", "A", "A", "A", "A", "B"),
  year = c(2000, 2001, 2000, 2001, 2000, 2001),
  type = c(TRUE, TRUE, FALSE, FALSE, FALSE, FALSE)
)

node_var_list <- node_vars %>%
  group_by(year) %>%
  group_split()

edge_vars <- data.frame(
  name1 = c("Actor 1", "Actor 1", "Actor 1"),
  name2 = c("Actor 2", "Actor 2", "Actor 3"),
  year = c(2000, 2001, 2000)
)

edge_var_list <- edge_vars %>%
  group_by(year) %>%
  group_split()

test_net1_bp <- as.network(x = edge_var_list[[1]], vertices = node_var_list[[1]],
                           directed = FALSE, bipartite = TRUE, bipartite_col = "type")

test_net2_bp <- as.network(x = edge_var_list[[2]], vertices = node_var_list[[2]],
                           directed = FALSE, bipartite = TRUE, bipartite_col = "type")

class(as.matrix(test_net1_bp)) # not a matrix

dim(as.matrix(test_net1_bp)) # returns NULL

[krivit]

Thanks for the report! Looks like a dimension is being dropped somewhere where it shouldn't be.