count the number of occurrences of “(” in a string

Question

I am trying to get the number of open brackets in a character string in R. I am using the str_count function from the stringr package

Answer 1

( is a special character. You need to escape it:

str_count(s,"\\(")
# [1] 3

Alternatively, given that you're using stringr, you can use the coll function:

str_count(s,coll("("))
# [1] 3