Map Names

We wish to rename columns of a data frame by providing a mapping from the current column names to the desired names for the columns whose names we wish to change. This is the recommended approach to column renaming (when it is possible).

In this example, we wish to change the names of two columns from col_a and col_b to col_1 and col_2 respectively.

df_2 = df %>% 
    rename(col_1 = col_a, col_2 = col_b)

Here is how this works:

• We use the function rename() from dplyr to change column names from their current values to the desired values.
• To rename columns, rename() expects a mapping between the current column names and the desired column names of the form desired_name = current_name which in this case is col_1 = col_a, col_2 = col_b.
• We only need to include mapping for the columns that we wish to rename. Columns that are not mentioned in the call to rename() will retain their current names.

Alternative: Rename while Selecting

df_2 = df %>% 
    select(col_1 = col_a, col_2 = col_b)

Here is how this works:

• The workhorse of selecting a subset of columns in the tidyverse is the select() function. See Selecting.
• While selecting columns via select(), we can rename them to the desired names by passing a mapping between the current column names and the desired column names of the form desired_name = current_name which in this case is col_1 = col_a, col_2 = col_b.
• This approach is a good fit when we wish to both select and rename (which is quite common).