Ignoring case when matching

Rather than transforming the input strings, another approach is to specify that the matching should be case insensitive. This is one of the options to the stringr regex() function.

Take our previous example,

x <- c("Cat", "CAT", "cAt") 
str_view(x, "cat")

To match the pattern cat in a case insensitive way, we wrap our pattern in regex() and specify the argument ignore_case = TRUE,

str_view(x, regex("cat", ignore_case = TRUE))

Notice that the matches retain their original case and any variant of cat matches.

Try it out to find the catcidents that involved tripping.

Deze oefening maakt deel uit van de cursus

String Manipulation with stringr in R

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Praktische interactieve oefening

Probeer deze oefening eens door deze voorbeeldcode in te vullen.

# View matches to "TRIP"
___

# Construct case insensitive pattern
trip_pattern <- ___

# View case insensitive matches to "TRIP"
___

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