R: How to ignore case when using str_detect?

Question

stringr package provides good string functions.

To search for a string (ignoring case)

one could use

stringr::str_detect(\'TOYOTA subaru\',ig         


        

Answer 1

the search string must be inside function fixed and that function has valid parameter ignore_case

str_detect('TOYOTA subaru', fixed('toyota', ignore_case=TRUE))

Answer 2

You can save a little typing with (?i):

c("Toyota", "my TOYOTA", "your Subaru") %>% 
  str_detect( "(?i)toyota" )
# [1]  TRUE  TRUE FALSE

Answer 3

You can use the base R function grepl() to accomplish the same thing without a nested function. It simply accepts ignore.case as an argument.

grepl("toyota", 'TOYOTA subaru', ignore.case = TRUE)

(Note that the order of the first two arguments (pattern and string) are switched between grepl and str_detect).

Answer 4

You can use regex (or fix as @lmo's comments depending on what you need) function to make the pattern as detailed in ?modifiers or ?str_detect (see the instruction for pattern parameter):

library(stringr)
str_detect('TOYOTA subaru', regex('toyota', ignore_case = T))
# [1] TRUE