## 13.6 DPLYR: Grammar of data management (Hadley Wickham)

• Functions
• filter(): Select a subset of the rows of a data frame (see also slice())
• arrange(): Reorders the rows of a data frame
• select(): Selects columns (can be used for renaming, see rename())
• distinct(): Returns unique values in a table
• mutate(): Add new columns to existing columns (see also transmute())
• summarise(): Collapses a data frame to a single row (e.g. aggregation)
• group_by(): Break data set into groups (of rows), to apply above functions to each group