为直接和间接连接的值创建组索引

Create a group index for values connected directly and indirectly

提问人:Malta 提问时间:7/13/2017 最后编辑:MaëlMalta 更新时间:8/3/2023 访问量:985

问:

我想生成索引,以根据两列对观测值进行分组。但我希望由共享的观察组成小组,至少在公共空间中有一个观察。

在下面的数据中,我想检查“G1”和“G2”中的值是直接连接(出现在同一行上),还是通过其他中间值间接连接。所需的分组变量以“g”表示。

例如,A 直接链接到 Z(第 1 行)和 X(第 2 行)。A 通过 X (A -> X -> B) 间接链接到“B”,并通过 X 和 B (A -> X -> B -> Y) 进一步链接到 Y。

dt <- data.frame(id = 1:10,
                 G1 = c("A","A","B","B","C","C","C","D","E","F"),
                 G2 = c("Z","X","X","Y","W","V","U","s","T","T"),
                 g = c(1,1,1,1,2,2,2,3,4,4))

dt
#    id G1 G2 g
# 1   1  A  Z 1
# 2   2  A  X 1
# 3   3  B  X 1
# 4   4  B  Y 1
# 5   5  C  W 2
# 6   6  C  V 2
# 7   7  C  U 2
# 8   8  D  s 3
# 9   9  E  T 4
# 10 10  F  T 4

我尝试过 from ,但没有成功。group_indicesdplyr

DPLYR iGraph R-常见问题解答

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答:

20赞 zx8754 7/13/2017 #1

使用 igraph get membership,然后映射名称:

library(igraph)

# convert to graph, and get clusters membership ids
g <- graph_from_data_frame(df1[, c(2, 3, 1)])
myGroups <- components(g)$membership

myGroups 
# A B C D E F Z X Y W V U s T 
# 1 1 2 3 4 4 1 1 1 2 2 2 3 4 

# then map on names
df1$group <- myGroups[df1$G1]


df1
#    id G1 G2 group
# 1   1  A  Z     1
# 2   2  A  X     1
# 3   3  B  X     1
# 4   4  B  Y     1
# 5   5  C  W     2
# 6   6  C  V     2
# 7   7  C  U     2
# 8   8  D  s     3
# 9   9  E  T     4
# 10 10  F  T     4