See how to join two data sets by one or more common columns using base R’s merge function, dplyr join functions, and the speedy data.table package. R has a number of quick, elegant ways to join ...

Quick LinksUsing a Column in a Formatted Excel TableUsing a Column in an Unformatted DatasetMicrosoft Excel's Data Validation ...

In this example, you combine selected columns from two data sets and edit them in a new data table. This example assumes that you have no data set loaded in the Analyst data table. If you do, select ...

“Hash tables are among the oldest data structures we have ... the last remaining open spot—is proportional to x. “If your hash table is 99 percent full,” Kuszmaul said, “it makes ...

For some data.table users, “dot-SD” is a bit of a mystery. But data.table creator Matt Dowle told me that it’s actually quite simple: Just think of it as a symbol representing “each group.” ...