4  Data frame dimensions

Minimal Active Learning Setup Example

4.1 Intro

One of the most basic operations when working with data is to get the dimensions of a dataset. This operation reports the number of rows and columns in the dataset.

4.2 Example

To get the dimensions of a data.frame in R we use the dim() function. For example, we can get the dimensions of the built-in iris dataset by running the following code. Click Run below and look at the output: it prints the number of rows, followed by the number of columns.

4.3 Practice

Your turn: Complete the following code to get the dimensions of the also built-in esoph dataset and assign it to a new object called esoph_dim:

Now, use the custom function check() to check your answer:

Explanation

Solution:

esoph_dim <- dim(esoph)

When applied on a data.frame, like iris or esoph above, the dim() function returns the number of rows and number of columns, in that order.

For more information, see ?dim.