How to extract unique values in multiple columns in an R data frame using a single line code?
To extract unique values in multiple columns in an R data frame, we first need to create a vector of the column values but for that we would need to read the columns in matrix form. After that we can simply unique function for the extraction. To understand how it works check out the below examples.
Consider the below data frame −
Example
Live Demo
x1<-rpois(20,2)
x2<-rpois(20,5)
x3<-rpois(20,2)
df1<-data.frame(x1,x2,x3)
df1
Output
x1 x2 x3
1 1 4 3
2 2 3 2
3 1 6 1
4 1 6 1
5 2 4 2
6 2 4 0
7 1 5 1
8 3 5 2
9 3 7 3
10 1 2 2
11 2 6 3
12 2 3 1
13 3 6 0
14 2 4 7
15 1 6 1
16 0 4 0
17 1 2 2
18 4 3 1
19 1 4 1
20 3 7 2
Extracting unique values in df1 −
Example
df1<-as.vector(as.matrix(df1))
unique(df1)
Output
[1] 1 2 3 0 4 6 5 7
Example
Live Demo
y1<-rpois(20,10)
y2<-rpois(20,20)
y3<-rpois(20,5)
df2<-data.frame(y1,y2,y3)
df2
Output
y1 y2 y3
1 8 24 5
2 5 19 2
3 8 17 1
4 10 21 5
5 8 27 3
6 12 14 5
7 8 19 3
8 11 26 10
9 11 25 5
10 6 20 7
11 4 26 3
12 7 21 6
13 14 21 3
14 11 18 7
15 11 13 6
16 7 17 5
17 9 21 7
18 5 20 6
19 16 24 7
20 8 14 1
Extracting unique values in df2 −
Example
df2<-as.vector(as.matrix(df2))
unique(df2)
Output
[1] 8 5 10 12 11 6 4 7 14 9 16 24 19 17 21 27 26 25 20 18 13 2 1 3
Published on 06-Feb-2021 08:19:17
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