forcats 🐈🐈🐈🐈

forcats provides tools for categorical variables (forcats is an anagram of factors).

Installation

You can install forcats from github with:

# install.packages("devtools")
devtools::install_github("hadley/forcats")

Key functions:

Change order of levels:

• fct_relevel(): move specified level up front.
• fct_inorder(): order by first appearance of each level.
• fct_reorder(): order by summary of another value.
• fct_infreq(): order by frequency.
• fct_shuffle(): randomly shuffle order of levels.
• fct_rev(): reverse order of levels.
• fct_shift(): shift levels to the left/right.

Change value of levels:

• fct_lump(): lump rarest (or most common) levels into "other".
• fct_recode(): manually recode levels.

Add new levels:

• fct_expand(): add new levels to a factor.
• fct_explicit_na(): turn missing values into an explicit factor.

A few other helpers:

• fct_c(): concatenate factors using union of levels.
• fct_count(): count occurences of levels, optionally sorting by frequency.
• fct_unify(): ensure list of factors share the same levels.
• fct_unique(): compute from levels of factor.
• fct_drop(): drop levels without data (same as base::droplevels()).
• lvls_union(): finds union of levels from list of factors.