Convert R Dataframe Column to a Vector

In this tutorial, we will look at how to convert a column in an R dataframe to a vector with the help of some examples.

How do you get column values as a vector in R?

You can use the [[]] notation to get an R dataframe’s column values as a vector using the column name or the column index.

The following is the syntax –

dataframe[[columan_name]]

We get the column values as a vector.

Steps to convert R dataframe column to a vector

Let’s now look at the steps to follow to get a column’s values as a vector in an R dataframe.

Step 1 – Create a dataframe

First, we will create a dataframe that we will be using throughout this tutorial.

# create a dataframe
employees_df = data.frame(
  "Name"= c("Jim", "Dwight", "Angela", "Tobi", "Kevin"),
  "Age"= c(26, 28, 29, 32, 30),
  "Department"= c("Sales", "Sales", "Accounting", "HR", "Accounting")
)
# display the dataframe
print(employees_df)

Output:

    Name Age Department
1    Jim  26      Sales
2 Dwight  28      Sales
3 Angela  29 Accounting
4   Tobi  32         HR
5  Kevin  30 Accounting

We now have a dataframe containing information about some employees working in an office. The dataframe has columns “Name”, “Age”, and “Department”.

Note that we use vectors here as column values to create a dataframe. You can think of a dataframe as vertical column vectors stacked side-by-side to form a tabular structure.

Step 2 – Get column value as a vector using [[]] notation

The values in a column are represented by a vector. Thus to get the vector of values for a column, we just need to access the column values which we can do using the [[]] notation.

Let’s now get the values in the “Name” column as a vector. For this, we’ll access the column values using the column name “Name”.

# get column "Name" values
names <- employees_df[["Name"]]
# display the vector
print(names)

Output:

[1] "Jim"    "Dwight" "Angela" "Tobi"   "Kevin" 

We get a vector of values from the “Name” column.

Note that you can also use the column index to access a column’s values. For example, in the above dataframe, the index of the “Name” column is 1 (rows and columns in R are indexed starting from 1).

# get column "Name" values
names <- employees_df[[1]]
# display the vector
print(names)

Output:

[1] "Jim"    "Dwight" "Angela" "Tobi"   "Kevin" 

We get the same result as above.

You might also be interested in –

• Create a DataFrame in R
• How to Add a Row to a Dataframe in R?
• How to Add a Column to a Dataframe in R?