Split a string by comma in Python

Split a string by comma in Python #

Use the str.split() method to split a string by comma, e.g. my_list = my_str.split(','). The str.split method will split the string on each occurrence of a comma and will return a list containing the results.

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# ✅ split string on each occurrence of comma
my_str = 'one,two,three,four'

my_list = my_str.split(',')
print(my_list)  # 👉️ ['one', 'two', 'three', 'four']

# ✅ split string on each space or comma
my_str_2 = 'one two,three four five'
my_list_2 = my_str_2.replace(',', ' ').split(' ')

print(my_list_2)  # 👉️ ['one', 'two', 'three', 'four', 'five']

The str.split() method splits the original string into a list of substrings using a delimiter.

The method takes the following 2 parameters:

If the separator is not found in the string, a list containing only 1 element is returned.

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my_str = 'one'

my_list = my_str.split(',')

# 👇️ ['one']
print(my_list)

If you have whitespace between the comma-separated words in the string and need to remove it, use the str.strip() method.

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my_str = 'one , two ,  three   ,four'

my_list = [item.strip() for item in my_str.split(',')]
print(my_list)  # 👉️ ['one', 'two', 'three', 'four']

We used a list comprehension to remove the leading and trailing whitespace from each string.

The str.strip method returns a copy of the string with the leading and trailing whitespace removed.

If your string starts with or ends with a comma, you would get empty string elements in the list.

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my_str = ',one,two,three,four,'

my_list = my_str.split(',')
print(my_list)  # 👉️ ['', 'one', 'two', 'three', 'four', '']

You can use the filter() function to remove any empty strings from the list.

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my_str = ',one,two,three,four,'

my_list = list(filter(None, my_str.split(',')))
print(my_list)  # 👉️ ['one', 'two', 'three', 'four']

The filter function takes a function and an iterable as arguments and constructs an iterator from the elements of the iterable for which the function returns a truthy value.

All values that are not truthy are considered falsy. The falsy values in Python are:

• constants defined to be falsy: None and False.
• 0 (zero) of any numeric type
• empty sequences and collections: "" (empty string), () (empty tuple), [] (empty list), {} (empty dictionary), set() (empty set), range(0) (empty range).

Note that the filter() function returns a filter object, so we have to use the list() class to convert the filter object to a list.

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my_str = 'one,two,three,four'


my_str_2 = 'one two,three four five'
my_list_2 = my_str_2.replace(',', ' ').split(' ')

print(my_list_2)  # 👉️ ['one', 'two', 'three', 'four', 'five']

We replaced all occurrences of a comma with a space and split the string on each space.

You could achieve the same result by replacing each occurrence of a space with a comma and splitting on each comma.

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my_str = 'one,two,three,four'

my_str_2 = 'one two,three four five'
my_list_2 = my_str_2.replace(' ', ',').split(',')

print(my_list_2)  # 👉️ ['one', 'two', 'three', 'four', 'five']