Custom Formats in gt Tables

The “grammar of tables” is used to build tables with the R-package gt. Thomas Mock published an extension package called gtExtras which is used all over in tweets about NFL and Fantasy Football such as win and loss history information in a table.

gt follows a similar philosophy such as ggplot2. On the one hand there is the data to be shown (in a table resp. a plot). On the other hand there is the description how to visualize the data: What is the table header, are there subheaders, how are the cells grouped and formated?

So it was time to check out gt. During my tryouts I came across one demand I haven’t found an in-built solution for: I wanted to format a column with respect to the value of another column. Here’s the way I solved it:

Working with tree-based hierarchies using data.tree

Lately I tried to visualize an hierarchy with Tableau Desktop. The problem was that the hierarchy had a variable depth because it was tree-based. Each row had an id and a parent_id. Normally hierarchies in Tableau are defined by pulling some fields together, such as product category, product group and product id.

Handling tree-based hierarchies seems to be a lot more complex. I found a plugin at but this only works online.

So I asked myself how I can handle this using R. I found the R-package data.tree at I want to describe how I use this package to preprocess my data.