Extract Row from Data Frame in R (2 Examples)
In this tutorial, I’ll illustrate how to return a certain row of a data frame in the R programming language.
The article looks as follows:
- Construction of Example Data
- Example 1: Get One Specific Row of Data Frame
- Example 2: Return Multiple Rows of Data Frame
- Video & Further Resources
Let’s start right away…
Construction of Example Data
We’ll use the following R data frame as example data for the following example.
data <- data.frame(x1 = 1:4, # Create example data x2 = 2:5, x3 = 9) data # Print example data # x1 x2 x3 # 1 1 2 9 # 2 2 3 9 # 3 3 4 9 # 4 4 5 9
As you can see based on the output of the RStudio console, our data consists of four rows and three numeric columns.
Example 1: Get One Specific Row of Data Frame
In case we want to extract a specific row of our example data, we can specify within square brackets the row index of the row we want to return. Consider the following R programming syntax:
data[2, ] # Extract row of data # x1 x2 x3 # 2 2 3 9
As you can see, the RStudio console returned the second row of our data frame.
Note that we had to specify the index of our row in front of a comma, in order to tell the R programming language that we want to extract a row. If we would specify the number 2 after the comma, we would extract a variable instead of a row.
Example 2: Return Multiple Rows of Data Frame
We can also extract multiple rows from a data frame in R. We simply need to specify a vector instead of a single value within the square brackets:
data[c(1, 4), ] # Get multiple rows # x1 x2 x3 # 1 1 2 9 # 4 4 5 9
In this example, we returned the first and the fourth row of our data.
Video & Further Resources
Do you need further info on the R syntax of this tutorial? Then you might have a look at the following video of my YouTube channel. In the video, I’m illustrating the examples of this article in RStudio:
In addition, you might read the other articles of my homepage:
- Subset Data Frame Rows by Logical Condition in R
- Sample Random Rows of Data Frame
- Extract Certain Columns of Data Frame
- R Functions List (+ Examples)
- The R Programming Language
At this point you should have learned how to access or subset a row with a particular index in a data matrix in R programming. If you have further questions, tell me about it in the comments below.