How to Find Unique Values and Sort Them in R

In this article, we will explore different methods to find unique values and sort them in R Programming Language.

Find Unique Values and Sort Them in R

Below are some of the ways by which we can find unique values and sort them sets in R

1. Using sort() with unique()
2. Using duplicated() and order()
3. Using table() for Frequency Counts
4. Using distinct() and arrange() from dplyr Package

Find Unique Values and Sort Them using sort() with unique()

In this approach, we use the unique() function to find unique values in a vector and then use the sort() function to sort them.

R

# R program to find and sort unique values
# using sort() with unique()
# Data of subject thought in class
subject <- c("MATH", "SCIENCE", "SCIENCE", "ENGLISH", "HINDI", "ENGLISH", "HINDI",
             "MATH","PHYSICS")

# Find unique values and sort them in ascending order
sorted_unique_values <- sort(unique(subject))
print(sorted_unique_values)

Output:

[1] "ENGLISH" "HINDI"  "MATH"   "PHYSICS" "SCIENCE"

Find Unique Values and Sort Them using duplicated() and order()

In this approach we use duplicated() to find unique rows in a dataframe and order() to sort them based on a specific column.

R

# R program to find and sort unique values
# using duplicated() and order()
# data frame of Customer transactions
customer_data <- data.frame(
  CustomerID = c(101, 102, 103, 101, 104),
  Amount = c(50, 30, 20, 50, 40)
)
customer_data
# Remove duplicate customers
unique_customers <- customer_data[!duplicated(customer_data$CustomerID), ]

# Sort unique customers by ID
sorted_unique_customers <- unique_customers[order(unique_customers$CustomerID), ]
print(sorted_unique_customers)

Output:

  CustomerID Amount
1        101     50
2        102     30
3        103     20
4        101     50
5        104     40
  CustomerID Amount
1        101     50
2        102     30
3        103     20
5        104     40

Find Unique Values and Sort Them using table() from Frequency Counts

In this approach we use table() to get the frequency counts of unique values, and then sort them using the sort() function.

R

#R program to find unique values and sort thedm
#using table() from Frequency Counts

# vector of data on Survey data on food preferences
food_preferences <- c("Pizza", "Burger", "Pizza", "Salad", "Pizza", "Burger",
                              "Salad", "Pizza", "Burger")

# Get frequency counts of unique preferences
preference_counts <- table(food_preferences)

# Sort preferences by count
sorted_preferences <- sort(preference_counts, decreasing = TRUE)
print(sorted_preferences)

Output:

food_preferences
 Pizza Burger  Salad 
     4      3      2 

Find Unique Values and Sort Them Using distinct() and arrange() from dplyr Package

In this method we use functions like distinct() and arrange() from dplyr package to find unique values and sort them using arrange() function.

R

# R program to find unique values and sort them in R
# Using distinct() and arrange() from dplyr Package
# Install and load the dplyr package if not already installed
# install.packages("dplyr")
library(dplyr)

# Sample data frame
df <- data.frame(
  Name = c("Vipul", "Jayesh", "Pratham", "Vipul"),
  Age = c(25, 30, 25, 35)
)

# Find unique values and sort them
sorted_unique_names <- df %>% distinct(Name) %>% arrange(Name)
print(sorted_unique_names)

Output:

      Name
1  Jayesh
2 Pratham
3   Vipul

Conclusion

In R, we explored different methods to find unique values and sort them, All of them have their advantage depending on the specific requirements of your data analysis tasks. By understanding and implementing these methods, we can streamline our data processing workflow and extract valuable insights from your datasets in R.