Using Melt to Loop Over a Vector in Data.table: Filtering and Summarizing with by

Removing Grouping Variables with R: Efficient Data Table Wrangling Strategies

Understanding How to Query Data.tables in R: A Step-by-Step Guide to Efficient Data Manipulation

Optimizing User-Defined Functions in data.table: A Performance-Centric Approach

Ranking Observations Across Multiple Groups Using R's Data Table Package

Improving Data Cleaning and Manipulation with R Programming Language

Applying Functions to Specific Columns in a data.table: A Powerful Approach to Data Manipulation

Creating a Group-by Table with Zero Padding for Missing Levels in R

Applying the `apply` Function Over Character Vectors Inside `data.table`: A Flexible Solution for Data Manipulation

Getting the Position of the Last Non-NA Value in a Row Using R Data.table