Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
How to find the unique combinations of a string vector elements with a fixed size in R?
A unique combination of vector elements can be found by using combn function with unique function and size argument will help us to identify the size of each of combination. For example, if we have a vector containing string values defined as x then the unique combinations of vector elements of size 2 can be created by using combn(unique(x),2).
Example1
x1<−c("A","B","C","A","D","E","A","C")
combn(unique(x1),2)Output
[,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"
Example
combn(unique(x1),3)
Output
[,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"
Example
combn(unique(x1),4)
Output
[,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"
Example
combn(unique(x1),5)
Output
[,1] [1,] "A" [2,] "B" [3,] "C" [4,] "D" [5,] "E"
Example2
x2<−c("India","Russia","India","USA","USA","UK","Egypt","UK")
combn(unique(x2),2)Output
[,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"
Example
combn(unique(x2),3)
Output
[,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"
Example
combn(unique(x2),4)
Output
[,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"
Example
combn(unique(x2),5)
Output
[,1] [1,] "India" [2,] "Russia" [3,] "USA" [4,] "UK" [5,] "Egypt"
Example3
x3<−c("G1","G2","G3","G1","G2","G4","G5","G3","G5","G2")
combn(unique(x3),2)Output
[,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"
Example
combn(unique(x3),3)
Output
[,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"
Example
combn(unique(x3),4)
Output
[,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"
Example
combn(unique(x3),5)
Output
[,1] [1,] "G1" [2,] "G2" [3,] "G3" [4,] "G4" [5,] "G5"
Example4
x4<−c("HOT","COLD","SWEET","BITTER","HOT","SWEET")
combn(unique(x4),2)Output
combn(unique(x4),2) [,1] [,2] [,3] [,4] [,5] [,6] [1,] "HOT" "HOT" "HOT" "COLD" "COLD" "SWEET" [2,] "COLD" "SWEET" "BITTER" "SWEET" "BITTER" "BITTER"
Example
combn(unique(x4),3)
Output
[,1] [,2] [,3] [,4] [1,] "HOT" "HOT" "HOT" "COLD" [2,] "COLD" "COLD" "SWEET" "SWEET" [3,] "SWEET" "BITTER" "BITTER" "BITTER"
Example
combn(unique(x4),4)
Output
[,1] [1,] "HOT" [2,] "COLD" [3,] "SWEET" [4,] "BITTER"
Updated on: 05-Feb-2021
928 Views
Advertisements