如何在R语言中查找字符串向量元素的固定大小的唯一组合?


可以使用`combn`函数结合`unique`函数来查找向量元素的唯一组合,`size`参数将帮助我们识别每个组合的大小。例如,如果我们有一个定义为x的包含字符串值的向量,则可以使用`combn(unique(x), 2)`创建大小为2的向量元素的唯一组合。

示例1

 在线演示

x1<−c("A","B","C","A","D","E","A","C")
combn(unique(x1),2)

输出

[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,] "A" "A" "A" "A" "B" "B" "B" "C" "C" "D"
[2,] "B" "C" "D" "E" "C" "D" "E" "D" "E" "E"

示例

combn(unique(x1),3)

输出

[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,] "A" "A" "A" "A" "A" "A" "B" "B" "B" "C"
[2,] "B" "B" "B" "C" "C" "D" "C" "C" "D" "D"
[3,] "C" "D" "E" "D" "E" "E" "D" "E" "E" "E"

示例

combn(unique(x1),4)

输出

[,1] [,2] [,3] [,4] [,5]
[1,] "A" "A" "A" "A" "B"
[2,] "B" "B" "B" "C" "C"
[3,] "C" "C" "D" "D" "D"
[4,] "D" "E" "E" "E" "E"

示例

combn(unique(x1),5)

输出

    [,1]
[1,] "A"
[2,] "B"
[3,] "C"
[4,] "D"
[5,] "E"

示例2

 在线演示

x2<−c("India","Russia","India","USA","USA","UK","Egypt","UK")
combn(unique(x2),2)

输出

[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9]
[1,] "India" "India" "India" "India" "Russia" "Russia" "Russia" "USA" "USA"
[2,] "Russia" "USA" "UK" "Egypt" "USA" "UK" "Egypt" "UK" "Egypt"
    [,10]
[1,] "UK"
[2,] "Egypt"

示例

combn(unique(x2),3)

输出

     [,1]     [,2]     [,3]   [,4]     [,5]   [,6]    [,7]     [,8]
[1,] "India" "India" "India" "India" "India" "India" "Russia" "Russia"
[2,] "Russia" "Russia" "Russia" "USA" "USA"   "UK"    "USA"    "USA"
[3,] "USA"    "UK"     "Egypt"  "UK"  "Egypt"  "Egypt" "UK" "Egypt"
      [,9] [,10]
[1,] "Russia" "USA"
[2,] "UK"     "UK"
[3,] "Egypt" "Egypt"

示例

combn(unique(x2),4)

输出

     [,1]  [,2] [,3] [,4] [,5]
[1,] "India" "India" "India" "India" "Russia"
[2,] "Russia" "Russia" "Russia" "USA" "USA"
[3,] "USA" "USA" "UK" "UK" "UK"
[4,] "UK" "Egypt" "Egypt" "Egypt" "Egypt"

示例

combn(unique(x2),5)

输出

      [,1]
[1,] "India"
[2,] "Russia"
[3,] "USA"
[4,] "UK"
[5,] "Egypt"

示例3

 在线演示

x3<−c("G1","G2","G3","G1","G2","G4","G5","G3","G5","G2")
combn(unique(x3),2)

输出

[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,] "G1" "G1" "G1" "G1" "G2" "G2" "G2" "G3" "G3" "G4"
[2,] "G2" "G3" "G4" "G5" "G3" "G4" "G5" "G4" "G5" "G5"

示例

combn(unique(x3),3)

输出

[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,] "G1" "G1" "G1" "G1" "G1" "G1" "G2" "G2" "G2" "G3"
[2,] "G2" "G2" "G2" "G3" "G3" "G4" "G3" "G3" "G4" "G4"
[3,] "G3" "G4" "G5" "G4" "G5" "G5" "G4" "G5" "G5" "G5"

示例

combn(unique(x3),4)

输出

[,1] [,2] [,3] [,4] [,5]
[1,] "G1" "G1" "G1" "G1" "G2"
[2,] "G2" "G2" "G2" "G3" "G3"
[3,] "G3" "G3" "G4" "G4" "G4"
[4,] "G4" "G5" "G5" "G5" "G5"

示例

combn(unique(x3),5)

输出

     [,1]
[1,] "G1"
[2,] "G2"
[3,] "G3"
[4,] "G4"
[5,] "G5"

示例4

 在线演示

x4<−c("HOT","COLD","SWEET","BITTER","HOT","SWEET")
combn(unique(x4),2)

输出

combn(unique(x4),2)
[,1] [,2] [,3] [,4] [,5] [,6]
[1,] "HOT" "HOT" "HOT" "COLD" "COLD" "SWEET"
[2,] "COLD" "SWEET" "BITTER" "SWEET" "BITTER" "BITTER"

示例

combn(unique(x4),3)

输出

[,1] [,2] [,3] [,4]
[1,] "HOT" "HOT" "HOT" "COLD"
[2,] "COLD" "COLD" "SWEET" "SWEET"
[3,] "SWEET" "BITTER" "BITTER" "BITTER"

示例

combn(unique(x4),4)

输出

      [,1]
[1,] "HOT"
[2,] "COLD"
[3,] "SWEET"
[4,] "BITTER"

更新于:2021年2月5日

1000+ 次浏览

开启您的职业生涯

完成课程获得认证

开始学习
广告