regular expression find strings with certain pattern in R

Question

I have some strings here and they are:

12ABC3, 2ABC45, ABC 56, uhyABC, REGEXP ...

The objective is as long as there is 'ABC' in a string (not 'BCA' or 'BAC') it should return TRUE when using 'grepl'

So the output should be

TRUE, TRUE, TRUE, TRUE, FALSE

Can anybody help me with this?

Thanks in advance

Answer 1

You want to use fixed = TRUE in your call to grepl.

> x <- c("12ABC3", "2ABC45", "ABC 56", "uhyABC", "REGEXP", "BCA", "CAB")
> grepl("ABC", x, fixed = TRUE)
# [1]  TRUE  TRUE  TRUE  TRUE FALSE FALSE FALSE

The fixed argument definition is

logical. If TRUE, pattern is a string to be matched as is. Overrides all conflicting arguments.

Answer 2

You can use the following.

> x <- c('12ABC3', '2ABC45', 'ABC 56', 'uhyABC', 'REGEXP')
> grepl('ABC', x, fixed=T)
# [1]  TRUE  TRUE  TRUE  TRUE FALSE
> x[grepl('ABC', x, fixed=T)]
# [1] "12ABC3" "2ABC45" "ABC 56" "uhyABC"