Revisions to How do I get a substring of a string in Python? [duplicate]

deleted 413 characters in body

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edited Dec 30, 2016 at 22:36

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I would like to add two points to the discussion:

You can use None instead on an empty space to specify "from the start" or "to the end":

 'abcde'[2:None] == 'abcde'[2:] == 'cde'

This is particularly helpful in functions, where you can't provide an empty space as an argument:

 def remove_from_tailsubstring(s, n_char=0start, end):
     """Remove `n``start` characters from the beginning and `end` 
     characters from the end of string `s`.

     Examples
     --------
     >>> remove_from_tailsubstring('abcde', 0, 3)
     'abcde''abc'
     >>> remove_from_tailsubstring('abcde', 21, None)
     'abc''bcde'
     """
     return s[s[start:-n_char if n_char > 0 else None]end]

Python has slice objects:

 idx = slice(2, None)
 'abcde'[idx] == 'abcde'[2:] == 'cde'

I would like to add two points to the discussion:

You can use None instead on an empty space to specify "from the start" or "to the end":

 'abcde'[2:None] == 'abcde'[2:] == 'cde'

This is particularly helpful in functions:

 def remove_from_tail(s, n_char=0):
     """Remove `n` characters from the end of string `s`.

     Examples
     --------
     >>> remove_from_tail('abcde', 0)
     'abcde'
     >>> remove_from_tail('abcde', 2)
     'abc'
     """
     return s[:-n_char if n_char > 0 else None]

Python has slice objects:

 idx = slice(2, None)
 'abcde'[idx] == 'abcde'[2:] == 'cde'

I would like to add two points to the discussion:

You can use None instead on an empty space to specify "from the start" or "to the end":

 'abcde'[2:None] == 'abcde'[2:] == 'cde'

This is particularly helpful in functions, where you can't provide an empty space as an argument:

 def substring(s, start, end):
     """Remove `start` characters from the beginning and `end` 
     characters from the end of string `s`.

     Examples
     --------
     >>> substring('abcde', 0, 3)
     'abc'
     >>> substring('abcde', 1, None)
     'bcde'
     """
     return s[start:end]

Python has slice objects:

 idx = slice(2, None)
 'abcde'[idx] == 'abcde'[2:] == 'cde'

added 191 characters in body

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edited Dec 30, 2016 at 22:30

ostrokach

reputation score 20420
12
12 gold badges
92
92 silver badges
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99 bronze badges

I would like to add two points to the discussion:

You can use None instead on an empty space to specify "from the start" or "to the end":

 'abcde'[2:None] == 'abcde'[2:] == 'cde'

This is particularly helpful in functions:

 def remove_from_tail(strings, n_char=Nonen_char=0):
     """Remove `n_char``n` characters from the end of `string`string `s`.

     Examples
     --------
     >>> remove_from_tail('abcde', 0)
     'abcde'
     >>> remove_from_tail('abcde', 2)
     'abc'
     """
     return string[s[:-n_char if n_char >=> 10 else None]

Python has slice objects:

 idx = slice(2, None)
 'abcde'[idx] == 'abcde'[2:] == 'cde'

I would like to add two points to the discussion:

You can use None instead on an empty space to specify "from the start" or "to the end":

 'abcde'[2:None] == 'abcde'[2:] == 'cde'

This is particularly helpful in functions:

 def remove_from_tail(string, n_char=None):
     """Remove `n_char` from the end of `string`."""
     return string[:-n_char if n_char >= 1 else None]

Python has slice objects:

 idx = slice(2, None)
 'abcde'[idx] == 'abcde'[2:] == 'cde'

I would like to add two points to the discussion:

You can use None instead on an empty space to specify "from the start" or "to the end":

 'abcde'[2:None] == 'abcde'[2:] == 'cde'

This is particularly helpful in functions:

 def remove_from_tail(s, n_char=0):
     """Remove `n` characters from the end of string `s`.

     Examples
     --------
     >>> remove_from_tail('abcde', 0)
     'abcde'
     >>> remove_from_tail('abcde', 2)
     'abc'
     """
     return s[:-n_char if n_char > 0 else None]

Python has slice objects:

 idx = slice(2, None)
 'abcde'[idx] == 'abcde'[2:] == 'cde'

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answered Aug 31, 2016 at 4:28

ostrokach

reputation score 20420
12
12 gold badges
92
92 silver badges
99
99 bronze badges

I would like to add two points to the discussion:

You can use None instead on an empty space to specify "from the start" or "to the end":

 'abcde'[2:None] == 'abcde'[2:] == 'cde'

This is particularly helpful in functions:

 def remove_from_tail(string, n_char=None):
     """Remove `n_char` from the end of `string`."""
     return string[:-n_char if n_char >= 1 else None]

Python has slice objects:

 idx = slice(2, None)
 'abcde'[idx] == 'abcde'[2:] == 'cde'

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