Python: Create group of similar items of a given list

Last update on April 22 2025 12:54:52 (UTC/GMT +8 hours)

42. Group Similar Items

Write a Python program to create groups of similar items from a given list.

Sample Solution:

Python Code:

import itertools as it 

def group_similar_items(seq):
    result =  [list(el) for _, el in it.groupby(seq, lambda x: x.split('_')[0])]
    return result 

colors = ['red_1', 'red_2', 'green_1', 'green_2', 'green_3', 'orange_1', 'orange_2']
print("Original list:")
print(colors)
print("\nGroup similar items of the said list:")
print(group_similar_items(colors))

colors = ['red_1', 'green-1', 'green_2', 'green_3', 'orange-1', 'orange_2']
print("\nOriginal list:")
print(colors)
print("\nGroup similar items of the said list:")
print(group_similar_items(colors))

Sample Output:

Original list:
['red_1', 'red_2', 'green_1', 'green_2', 'green_3', 'orange_1', 'orange_2']

Group similar items of the said list:
[['red_1', 'red_2'], ['green_1', 'green_2', 'green_3'], ['orange_1', 'orange_2']]

Original list:
['red_1', 'green-1', 'green_2', 'green_3', 'orange-1', 'orange_2']

Group similar items of the said list:
[['red_1'], ['green-1'], ['green_2', 'green_3'], ['orange-1'], ['orange_2']]

For more Practice: Solve these Related Problems:

• Write a Python program to group similar items from a list into sublists based on a custom equality function using itertools.groupby.
• Write a Python program to partition a list into groups of similar elements and then map a function to each group to compute its length.
• Write a Python program to create an iterator that groups elements with the same property and then converts each group into a sorted list.
• Write a Python program to use itertools.groupby to cluster a list into groups and then filter out groups with a single element.

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Python Code Editor:

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