具有特定屬性值的連接節點的圖形數目

Question

我有一個圖：

g <- make_empty_graph (2) %>%
  set_vertex_attr("a", value = 1) %>%
  add_vertices(2, color = 2, "a" = 2) %>%
  add_vertices(2, color = 4, "a" = 3) %>%
  add_edges(c(1, 2, 2, 1, 1, 5, 5, 1, 1, 4, 4, 1))
plot(g)

有沒有一種方法可以找出有多少個屬性“ a”的值為2的節點連接到節點“ 1”？

Answer 1

您可以使用neighbors獲取節點1的neighbors ，然后測試哪些neighbors具有“ a” = 2。

NeighborList = neighbors(g, 1)
NeighborList[NeighborList$a == 2]
+ 1/6 vertex, from 3502fa5:
[1] 4