stringr: info

• Overview
• Cheatsheet
• Reading

stringr helps us manipulate strings!

The package includes many functions to help us with regular expressions, which are a concise language for describing patterns in strings.

These functions help us

• detect matches
• subset strings
• manage string lengths
• mutate strings
• join and split strings
• order strings
• …and more!

PDF: https://github.com/rstudio/cheatsheets/raw/main/strings.pdf

R for Data Science: Ch 14 Strings

Package documentation: https://stringr.tidyverse.org

stringr: exercise

• Mutate
• Join

What does this chunk do?

penguins |>
  select(species, island) |>
  mutate(ISLAND = str_to_upper(island))

# A tibble: 344 × 3
   species island    ISLAND   
   <fct>   <fct>     <chr>    
 1 Adelie  Torgersen TORGERSEN
 2 Adelie  Torgersen TORGERSEN
 3 Adelie  Torgersen TORGERSEN
 4 Adelie  Torgersen TORGERSEN
 5 Adelie  Torgersen TORGERSEN
 6 Adelie  Torgersen TORGERSEN
 7 Adelie  Torgersen TORGERSEN
 8 Adelie  Torgersen TORGERSEN
 9 Adelie  Torgersen TORGERSEN
10 Adelie  Torgersen TORGERSEN
# … with 334 more rows

How about this one?

penguins |>
  select(species, island) |>
  mutate(ISLAND = str_to_upper(island)) |>
  mutate(species_island = str_c(species, ISLAND, sep = "_"))

# A tibble: 344 × 4
   species island    ISLAND    species_island  
   <fct>   <fct>     <chr>     <chr>           
 1 Adelie  Torgersen TORGERSEN Adelie_TORGERSEN
 2 Adelie  Torgersen TORGERSEN Adelie_TORGERSEN
 3 Adelie  Torgersen TORGERSEN Adelie_TORGERSEN
 4 Adelie  Torgersen TORGERSEN Adelie_TORGERSEN
 5 Adelie  Torgersen TORGERSEN Adelie_TORGERSEN
 6 Adelie  Torgersen TORGERSEN Adelie_TORGERSEN
 7 Adelie  Torgersen TORGERSEN Adelie_TORGERSEN
 8 Adelie  Torgersen TORGERSEN Adelie_TORGERSEN
 9 Adelie  Torgersen TORGERSEN Adelie_TORGERSEN
10 Adelie  Torgersen TORGERSEN Adelie_TORGERSEN
# … with 334 more rows