How to find the unique values in a column of R dataframe?
In this article, we will discuss how to find out the unique value in a column of dataframe in R Programming language. For this task, unique() function is used where the column name is passed for which unique values are to be printed.
Syntax: unique(x)
parameters:
- x: data frame
For a column name select the column using $
dataframe$column_name
Example 1:
R
id<- c (1,2,3,4,5,6,7,8,9) country <- c ( "INDIA" , "AMERICA" , "JAPAN" , "CHINA" , "BANGLADESH" , "SRILANKA" , "NEPAL" , "AMERICA" , "CHINA" ) data<- data.frame (id,country) unique (data$country) |
Output:
[1] INDIA AMERICA JAPAN CHINA BANGLADESH SRILANKA NEPAL
Levels: AMERICA BANGLADESH CHINA INDIA JAPAN NEPAL SRILANKA
Example 2:
R
data <- data.frame (x1 = c (9, 5, 6, 8, 9), x2 = c (2, 4, 2, 7, 1), x3 = c (3,6,7,0,3), x4 = c ( "Hello" , "value" , "value" , "w3wiki" , NA ) ) unique (data[ c ( "x2" )]) unique (data[ c ( "x1" )]) |
Output:
Unique data in column x2
x2
1 2
2 4
4 7
5 1
Unique data in column x1
x1
1 9
2 5
3 6
4 8
Example 3:
R
data<- data.frame (Student= c ( 'John' , 'Lee' , 'Guy' , 'John' , 'Lee' , 'Guy' ), Age= c (18,19,20,18,19,20), Gender= c ( 'Male' , 'Female' , 'Male' , 'Male' , 'Female' , 'Male' )) unique (data) |
Output: