Count Specified Patterns in a String

str_count() counts the number of occurrences of a specific pattern in a string. In the following example, we count the number of letter “a” in each of the fruit names.

fruit <- c("apple", "banana", "pear", "kiwi")library(stringr)str_count(fruit, pattern = "a")

Output:
[1] 1 3 1 0

Here we count the letter of “a”, “b”, “p”, and “p”, respectively, in each of the four fruit names. Note that the length of the pattern is the same as the input vector fruit.

str_count(fruit, pattern = c("p", "a", "e", "i"))

Output:
[1] 2 3 1 2