Работа со строками python split

split¶

Returns a list of the words in the string, separated by the delimiter string.

Syntax¶

str. split([sep[, maxsplit]])

sep Optional. Character dividing the string into split groups; default is space. maxsplit Optional. Number of splits to do; default is -1 which splits all the items.

Return Value¶

Time Complexity¶

Remarks¶

If sep is given, consecutive delimiters are not grouped together and are deemed to delimit empty strings (for example,

returns [‘1’, ‘’, ‘2’]). The sep argument may consist of multiple characters (for example,

returns [‘1’, ‘2’, ‘3’]). Splitting an empty string with a specified separator returns [‘’].

If sep is not specified or is None, a different splitting algorithm is applied: runs of consecutive whitespace are regarded as a single separator, and the result will contain no empty strings at the start or end if the string has leading or trailing whitespace. Consequently, splitting an empty string or a string consisting of just whitespace with a None separator returns [].

Example 1¶

>>> ' a b c '.split() ['a', 'b', 'c'] >>> ' a b c '.split(None) ['a', 'b', 'c'] >>> ' a b c '.split(' ', 1) ['', 'a b c '] >>> ' a b c '.split(' ', 2) ['', 'a', 'b c '] >>> ' a b c '.split(' ', 3) ['', 'a', 'b', 'c '] >>> ' a b c '.split(' ', 4) ['', 'a', 'b', 'c', ''] >>> ' a b c '.split(' ', 5) ['', 'a', 'b', 'c', ''] 

Example 2¶

>>> '-a-b-c-'.split('-') ['', 'a', 'b', 'c', ''] >>> '-a-b-c-'.split('-', 1) ['', 'a-b-c-'] >>> '-a-b-c-'.split('-', 2) ['', 'a', 'b-c-'] >>> '-a-b-c-'.split('-', 3) ['', 'a', 'b', 'c-'] >>> '-a-b-c-'.split('-', 4) ['', 'a', 'b', 'c', ''] >>> '-a-b-c-'.split('-', 5) ['', 'a', 'b', 'c', ''] 

Example 3¶

>>> '----a---b--c-'.split('-') ['', '', '', '', 'a', '', '', 'b', '', 'c', ''] >>> '----a---b--c-'.split('-', 1) ['', '---a---b--c-'] >>> '----a---b--c-'.split('-', 2) ['', '', '--a---b--c-'] >>> '----a---b--c-'.split('-', 3) ['', '', '', '-a---b--c-'] >>> '----a---b--c-'.split('-', 4) ['', '', '', '', 'a---b--c-'] >>> '----a---b--c-'.split('-', 5) ['', '', '', '', 'a', '--b--c-'] >>> '----a---b--c-'.split('-', 6) ['', '', '', '', 'a', '', '-b--c-'] 

See Also¶

rsplit() for version that splits from the right

© Copyright 2015, Jakub Przywóski. Revision 9a3b94e7 .

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Python .split() – Splitting a String in Python

Dionysia Lemonaki

In this article, you will learn how to split a string in Python.

Firstly, I’ll introduce you to the syntax of the .split() method. After that, you will see how to use the .split() method with and without arguments, using code examples along the way.

Here is what we will cover:

What Is The .split() Method in Python? .split() Method Syntax Breakdown

You use the .split() method for splitting a string into a list.

The general syntax for the .split() method looks something like the following:

string.split(separator, maxsplit) 

• string is the string you want to split. This is the string on which you call the .split() method.
• The .split() method accepts two arguments.
• The first optional argument is separator , which specifies what kind of separator to use for splitting the string. If this argument is not provided, the default value is any whitespace, meaning the string will split whenever .split() encounters any whitespace.
• The second optional argument is maxsplit , which specifies the maximum number of splits the .split() method should perform. If this argument is not provided, the default value is -1 , meaning there is no limit on the number of splits, and .split() should split the string on all the occurrences it encounters separator .

The .split() method returns a new list of substrings, and the original string is not modified in any way.

How Does The .split() Method Work Without Any Arguments?

Here is how you would split a string into a list using the .split() method without any arguments:

coding_journey = "I am learning to code for free with freeCodecamp!" # split string into a list and save result into a new variable coding_journey_split = coding_journey.split() print(coding_journey) print(coding_journey_split) # check the data type of coding_journey_split by using the type() function print(type(coding_journey_split)) # output # I am learning to code for free with freeCodecamp! # ['I', 'am', 'learning', 'to', 'code', 'for', 'free', 'with', 'freeCodecamp!'] #

The output shows that each word that makes up the string is now a list item, and the original string is preserved.

When you don’t pass either of the two arguments that the .split() method accepts, then by default, it will split the string every time it encounters whitespace until the string comes to an end.

What happens when you don’t pass any arguments to the .split() method, and it encounters consecutive whitespaces instead of just one?

coding_journey = "I love coding" coding_journey_split = coding_journey.split() print(coding_journey_split) # output # ['I', 'love', 'coding'] 

In the example above, I added consecutive whitespaces between the word love and the word coding . When this is the case, the .split() method treats any consecutive spaces as if they are one single whitespace.

How Does The .split() Method Work With The separator Argument?

As you saw earlier, when there is no separator argument, the default value for it is whitespace. That said, you can set a different separator .

The separator will break and divide the string whenever it encounters the character you specify and will return a list of substrings.

For example, you could make it so that a string splits whenever the .split() method encounters a dot, . :

fave_website = "www.freecodecamp.org" fave_website_split = fave_website.split(".") print(fave_website_split) # output # ['www', 'freecodecamp', 'org'] 

In the example above, the string splits whenever .split() encounters a .

Keep in mind that I didn’t specify a dot followed by a space. That wouldn’t work since the string doesn’t contain a dot followed by a space:

fave_website = "www.freecodecamp.org" fave_website_split = fave_website.split(". ") print(fave_website_split) # output # ['www.freecodecamp.org'] 

Now, let’s revisit the last example from the previous section.

When there was no separator argument, consecutive whitespaces were treated as if they were single whitespace.

However, when you specify a single space as the separator , then the string splits every time it encounters a single space character:

coding_journey = "I love coding" coding_journey_split = coding_journey.split(" ") print(coding_journey_split) # output # ['I', 'love', '', '', 'coding'] 

In the example above, each time .split() encountered a space character, it split the word and added the empty space as a list item.

How Does The .split() Method Work With The maxsplit Argument?

When there is no maxsplit argument, there is no specified limit for when the splitting should stop.

In the first example of the previous section, .split() split the string each and every time it encountered the separator until it reached the end of the string.

However, you can specify when you want the split to end.

For example, you could specify that the split ends after it encounters one dot:

fave_website = "www.freecodecamp.org" fave_website_split = fave_website.split(".", 1) print(fave_website_split) # output # ['www', 'freecodecamp.org'] 

In the example above, I set the maxsplit to 1 , and a list was created with two list items.

I specified that the list should split when it encounters one dot. Once it encountered one dot, the operation would end, and the rest of the string would be a list item on its own.

Conclusion

And there you have it! You now know how to split a string in Python using the .split() method.

I hope you found this tutorial helpful.

To learn more about the Python programming language, check out freeCodeCamp’s Python certification.

You’ll start from the basics and learn in an interactive and beginner-friendly way. You’ll also build five projects at the end to put into practice and help reinforce what you’ve learned.

Thank you for reading, and happy coding!

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