Find last occurrence of a data frame in R

In this article, we will explore various methods to find the last occurrence in a data frame by using the R Programming Language.

R language offers various methods to find the last occurrence in a data frame. By using these methods provided by R, it is possible to find every occurrence. Some of the methods to find the last occurrence are:

Find the last occurrence in the data frame By using the ‘tail()’ function

It is a method, that can find every occurrence in a data frame. In this example, we created a data frame and found the last occurrence of it.

R

#creating data frame
df <- data.frame(
  Name= c("A", "B", "C", "D", "E", "F"),
  Age= c(8,7,6,5,3,2)
)

print(df)
print("The last occurrence is")

# Finding the last occurrence of a specific element
tail(df,1)

Output:

  Name Age
1    A   8
2    B   7
3    C   6
4    D   5
5    E   3
6    F   2

[1] "The last occurrence is"
  Name Age
6    F   2

In this example, we created a dataframe and finded the last occurrence of it.

R

ID= c(8,7,6,5,3,2)
Name= c("Ravi", "Rakesh", "Suresh", "Naresh", "Lokesh", "Sukesh")
df <- data.frame(ID,Name)

print(df)

# Finding the last occurrence of a specific element
print("The last occurrence is")
tail(df,1)

Output:

  ID   Name
1  8   Ravi
2  7 Rakesh
3  6 Suresh
4  5 Naresh
5  3 Lokesh
6  2 Sukesh

[1] "The last occurrence is"
  ID   Name
6  2 Sukesh

Find last occurrence in data frame By using the ‘which.max()’ function

It is method, that have ability to find every occurrence in a data frame. In this example, we created a dataframe and finded the last occurrence of it.

R

# Creating data frame
df <- data.frame(Name= c("A","B","C","D","E"),
                 Age = c(25,35,45,30, 40))

print(df)
# Finding the last occurrence
last_index <- which.max(df$Age == 40)

print("The last occurence is")
res <- df[last_index, ]
res

Output:

  Name Age
1    A  25
2    B  35
3    C  45
4    D  30
5    E  40

[1] "The last occurence is"
  Name Age
5    E  40

In this example, we created a dataframe and finded the last occurrence of it.

R

Name= c("Ravi","Rakesh","Karim","Kavya","sakesh", "Ramya")
ID = c(25,35,45,23,29,42)

df <- data.frame(Name, ID)        

print(df)
# Finding the last occurrence
last_index <- which.max(df$ID == 42)

print("The last occurence is")
res <- df[last_index, ]
res

Output:

   Name ID
1   Ravi 25
2 Rakesh 35
3  Karim 45
4  Kavya 23
5 sakesh 29
6  Ramya 42

[1] "The last occurence is"
   Name ID
6 Ramya 42

Conclusion

In conclusion, we learned about how to find the last occurrence of a data frame by using various methods. R languages provides various functions while dealing with the last occurence.