6.2. dplyr

dplyr is a grammar for data manipulation. It provides a consistent set of operations which are sufficient to take care of most data manipulation tasks.

In a data frame we have columns representing different variables and rows representing different records.

The typical data manipulation tasks are:

• Selecting few variables (columns) from a data set
• Filtering the rows (cases) based on the values of specific variables (columns)
• Summarizing (reducing) the dataset