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.
Это упражнение является частью курса
String Manipulation with stringr in R
Интерактивное практическое упражнение
Попробуйте выполнить это упражнение, дополнив этот пример кода.
# View matches to "TRIP"
___
# Construct case insensitive pattern
trip_pattern <- ___
# View case insensitive matches to "TRIP"
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