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Super Kai (Kazuya Ito)
Super Kai (Kazuya Ito)

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String in Python (7)

#python #string #str #function

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*Memos:

replace() can replace the zero or more old substrings of a string with a new substring from the left to the right as shown below:

*Memos

  • The 1st argument is old(Required-Type:str): *Memos:
    • It's the substring replaced with new.
    • Don't use old=.
  • The 2nd argument is new(Required-Type:str): *Memos:
    • It's the substring replacing old.
    • Don't use old=.
  • The 3rd argument is count(Optional-Default:-1-Type:int): *Memos:
    • It decides how many matched substrings are replaced.
    • If it's -1, all old substrings are replaced.
    • Don't use count=. 
v = "It's very very good" print(v.replace('er', 'ER')) print(v.replace('er', 'ER', -1)) print(v.replace('er', 'ER', 2)) # It's vERy vERy good  print(v.replace('er', 'ER', 1)) # It's vERy very good  print(v.replace('very', 'VERY')) print(v.replace('very', 'VERY', 2)) # It's VERY VERY good  print(v.replace('very', 'VERY', 1)) # It's VERY very good  print(v.replace('', '--')) # --I--t--'--s-- --v--e--r--y-- --v--e--r--y-- --g--o--o--d--  # ↓↓ print(v.replace('', ' ')) # I t ' s v e r y v e r y g o o d  # ↓ ↓↓ print(v.replace(' ', ' ')) # It's very very good  # ↓↓ ↓ print(v.replace(' ', ' ')) print(v.replace('', '')) print(v.replace('er', 'ER', 0)) print(v.replace('very', 'VERY', 0)) print(v.replace('ER', 'ER')) print(v.replace('VERY', 'VERY')) print(v.replace('really', 'VERY')) # It's very very good
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removeprefix() can remove the prefix of a string as shown below:

*Memos

  • The 1st argument is prefix(Required-Type:str): *Memos:
    • It's the prefix of zero or more characters.
    • Don't use prefix=. 
v = 'hello world' print(v.removeprefix('he')) # llo world print(v.removeprefix('hello ')) # world print(v.removeprefix('hello wo')) # rld  print(v.removeprefix('HE')) print(v.removeprefix('')) print(v.removeprefix('abc')) # hello world
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removesuffix() can remove the suffix of a string as shown below:

*Memos

  • The 1st argument is suffix(Required-Type:str): *Memos:
    • It's the suffix of zero or more characters.
    • Don't use suffix=. 
v = 'hello world' print(v.removesuffix('ld')) # hello wor print(v.removesuffix(' world')) # hello print(v.removesuffix('lo world')) # hel  print(v.removesuffix('LD')) print(v.removesuffix('')) print(v.removesuffix('abc')) # hello world
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join() can concatenate the zero or more elements of an iterable as shown below:

*Memos

  • The 1st argument is iterable(Required-Type:iterable).
  • Don't use iterable=. 
v = ['one', 'two', 'three', 'four', 'five'] print(''.join(v)) # onetwothreefourfive print(' '.join(v)) # one two three four five print(' '.join(v)) # one two three four five print('-'.join(v)) # one-two-three-four-five print(' - '.join(v)) # one - two - three - four - five print('<->'.join(v)) # one<->two<->three<->four<->five
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v = [] print('-'.join(v)) # Nothing
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v = [0, 12, 345, 6789] print(''.join(map(str, v))) print(''.join([str(num) for num in v])) # 0123456789  print('-'.join(map(str, v))) print('-'.join([str(num) for num in v])) # 0-12-345-6789
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