Python: Flatten a shallow list
Python List: Exercise - 23 with Solution
Write a Python program to flatten a shallow list.
Example - 1 :

Example - 2 :

Example - 3 :

Sample Solution-1:
Python Code:
import itertools
original_list = [[2,4,3],[1,5,6], [9], [7,9,0]]
new_merged_list = list(itertools.chain(*original_list))
print(new_merged_list)
Sample Output:
[2, 4, 3, 1, 5, 6, 9, 7, 9, 0]
Visualize Python code execution:
The following tool visualize what the computer is doing step-by-step as it executes the said program:
Sample Solution-2:
Use a list comprehension to extract each value from sub-lists in order.
Python Code:
def flatten(nums):
return [x for y in nums for x in y]
nums = [[1, 2, 3, 4], [5, 6, 7, 8]]
print("Original list elements:")
print(nums)
print("\nFlatten the said list:")
print(flatten(nums))
nums = [[2,4,3],[1,5,6], [9], [7,9,0]]
print("\nOriginal list elements:")
print(nums)
print("\nFlatten the said list:")
print(flatten(nums))
Sample Output:
Original list elements: [[1, 2, 3, 4], [5, 6, 7, 8]] Flatten the said list: [1, 2, 3, 4, 5, 6, 7, 8] Original list elements: [[2, 4, 3], [1, 5, 6], [9], [7, 9, 0]] Flatten the said list: [2, 4, 3, 1, 5, 6, 9, 7, 9, 0]
Flowchart:

Visualize Python code execution:
The following tool visualize what the computer is doing step-by-step as it executes the said program:
Python Code Editor:
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Previous: Write a Python program to find the index of an item in a specified list.
Next: Write a Python program to append a list to the second list.
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Python: Tips of the Day
Given a predicate function, fn, and a prop string, this curried function will then take an object to inspect by calling the property and passing it to the predicate:
Example:
def tips_check_prop(fn, prop): return lambda obj: fn(obj[prop]) check_age = tips_check_prop(lambda x: x >= 25, 'age') user = {'name': 'Owen', 'age': 25} print(check_age(user))
Output:
True
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