10. String operations

https://note.nkmk.me/en/python-str-replace-translate-re-sub/

Here's how to replace strings in Python.

• Replace substrings: replace()

  • Specify the maximum count of replacements: count

  • Replace multiple different substrings

  • Replace newline character

• Replace multiple different characters: translate()

• Replace with regular expression: re.sub(), re.subn()

  • Replace multiple substrings with the same string

  • Replace using the matched part

  • Get the count of replaced parts

• Replace by position: slice

Regular Expression

re.search()

Python

for text in df['simplified'][:3]:
    hit = re.search(p, text)
    print(hit)
    print(hit.start(), hit.end())
    print(hit.group())

output

<re.Match object; span=(0, 3), match='特朗普'>
0 3
特朗普
<re.Match object; span=(0, 2), match='美国'>
0 2
美国
<re.Match object; span=(13, 15), match='美国'>
13 15

re.finditer()

因為是iterator的關係，可用

Python

hits = re.finditer(p, "這個哈哈哈美帝真的北美很討厭")
# print(next(hits))
for h in hits:
    print(h.start(), h.end(), h.group())

output

5 7 美帝
9 11 北美