How to add column to dataframe in R ?

In this article, we are going to see how to add columns to dataframe in R. First, let’s create a sample dataframe.

Adding Column to the DataFrame

We can add a column to a data frame using $ symbol.

syntax: dataframe_name $ column_name = c( value 1,value 2 . . . , value n) 

Here c() function is a vector holds values .we can pass any type of data with similar type.  

Steps for adding a column to a dataframe.

1. Create a data frame.
2. Use the $ symbol as shown in the above syntax to add a column to a data frame.
3. Print the updated data frame to see the changes.

Example 1: Creating a data frame.

R

# Creating a data frame with eid , ename,salary as columns
df2 = data.frame(eid = c(1, 2, 3),
                 ename = c("karthik", "nikhil", "sravan"),
                 salary = c(50000, 60000, 70000))

# printing the data frame
print(df2)

Adding a column using $ symbol:

R

# creating a data frame
df2 = data.frame(eid = c(1, 2, 3),
                 ename = c("karthik", "nikhil", "sravan"),
                 salary = c(50000, 60000, 70000))

# adding a new column to the data frame using $ symbol
df2$designation = c("data scientist", "senior manager", "HR")

# printing the updated data frame
print(df2)

Example 2: Creating a data frame

R

# creating a data frame using vectors
df1 = data.frame(id = c(1, 2 ,3),
                 name = c("karthik", "nikhil", "sravan"))

# printing the data frame
print(df1)

Adding a column to the data frame

R

# creating a data frame
df1 = data.frame(id = c(1, 2, 3),
                 name = c("karthik", "nikhil", "sravan"))
# adding a new column to the data frame using $ symbol
df1$branch = c("IT", "CSE", "IT")

# printing the updated data frame
print(df1)