Category: R

Steven Sanderson shows off some more complex string splitting scenarios in R:

In data preprocessing and text manipulation tasks, the strsplit() function in R is incredibly useful for splitting strings based on specific delimiters. However, what if you need to split a string using multiple delimiters? This is where strsplit() can really shine by allowing you to specify a regular expression that defines these delimiters. In this blog post, we’ll dive into how you can use strsplit() effectively with multiple delimiters to parse strings in your data.

Read on for two examples of complex scenarios.

Steven Sanderson performs feature selection:

As an R programmer, one of the fundamental tasks you’ll encounter is manipulating data frames. Whether you’re cleaning messy data or preparing it for analysis, knowing how to drop unnecessary columns is a valuable skill. In this guide, we’ll walk through the process of dropping columns from data frames in R, using simple examples to demystify the process.

Read on for three ways of doing this.

Steven Sanderson searches for subsets:

In data analysis, there often arises a need to extract the top N values within each group of a dataset. Whether you’re dealing with sales data, survey responses, or any other type of grouped data, identifying the top performers or outliers within each group can provide valuable insights. In this tutorial, we’ll explore how to accomplish this task using three popular R packages: dplyr, data.table, and base R. By the end of this guide, you’ll have a solid understanding of various approaches to selecting top N values by group in R.

Read on for the three examples.

Steven Sanderson wants to check for row existence:

Hello, fellow R users! Today, we’re going to explore a common scenario you might encounter when working with data frames: checking if a row from one data frame exists in another. This is a handy skill that can help you compare datasets and verify data integrity.

There are several ways to do it. Click through for two of those ways.

Steven Sanderson takes a slice:

Explanation: – We use nrow(my_df) to get the total number of rows in the data frame. – Then, we use indexing ([nrow(my_df), ]) to extract the last row.

Read on for a simple example of getting the last row using base R, dplyr, and data.table. Then, we kick it up a notch to get the second-to-last row, with the idea being that you could substitute “second-to-last” with any arbitrary number.