Replacing with regular expressions

Now, you've mastered matching with backreferences, you'll build up to replacing with backreferences, but first let's review str_replace() now that you've got regular expressions under your belt.

Remember str_replace() takes three arguments, string a vector of strings to do the replacements in, pattern that identifies the parts of strings to replace and replacement the thing to use as a replacement.

replacement can be a vector, the same length as string, each element specifies the replacement to be used in each string. Let's practice by anonymizing some of the contact objects you've seen so far.

이 연습은 강의의 일부입니다

String Manipulation with stringr in R

강의 보기

연습 안내

Text containing phone numbers has been pre-defined in a variable named contact.

Replace a digit in contact with "X" using str_replace().
Replace all digits in contact with "X" using str_replace_all(). (str_replace() will only replace the first match to the pattern. str_replace_all() will replace all matches to the pattern.)
Replace all digits in contact using str_replace_all(), but now specify the vector c("X", ".", "*", "_") as replacement. Notice how now each string uses a different replacement character.

실습형 인터랙티브 연습

이 예제를 이 샘플 코드를 완성하여 풀어보세요.

# View text containing phone numbers
contact

# Replace digits with "X"
str_replace(contact, DGT, ___)

# Replace all digits with "X"
str_replace_all(contact, DGT, ___)

# Replace all digits with different symbol
str_replace_all(contact, DGT, ___)

코드 편집 및 실행