Since dplyr functions operate on data frames using column names, it is often useful to update the column names of a data frame so they are as clear and meaningful as possible. dplyr’s rename()
function allows you to easily do this.
Say you have a data frame of books, as shown in the table below:
name | written_by |
---|---|
The Lord of the Rings | J. R. R. Tolkien |
Le Petit Prince | Antoine de Saint-Exupéry |
Harry Potter and the Philosopher’s Stone | J. K. Rowling |
紅樓夢/红楼梦 | Cao Xueqin |
rename()
can take any number of arguments, where each new column name is assigned to replace an old column name in the format new_column_name = old_column_name
. rename()
returns a new data frame with the updated column names.
To update the name
column to book_title
and the written_by
column to author
:
df %>% rename(book_title = name, author = written_by)
You can confirm the names of the columns have been updated using either of the base R functions names()
or colnames()
, which take a data frame as an argument and return a vector containing the column names.
Instructions
The updated dogs
data frame from the previous exercise is given to you in notebook.Rmd
. Save the column names of dogs
to original_col_names
and print it.
Update the name of avg_height
to avg_height_inches
, avg_weight
to avg_weight_lbs
, and rank_change_13_to_16
to popularity_change_13_to_16
. Save the updated data frame to dogs
.
Save the new column names of dogs
to new_col_names
and print it.