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Python map() and lambda() Use Cases and Examples

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 In Python, map() and lambda functions are often used together for functional programming. Here are some examples to illustrate how they work. Python map and lambda top use cases 1. Using map() with lambda The map() function applies a given function to all items in an iterable (like a list) and returns a map object (which can be converted to a list). Example: Doubling Numbers numbers = [ 1 , 2 , 3 , 4 , 5 ] doubled = list ( map ( lambda x: x * 2 , numbers)) print (doubled) # Output: [2, 4, 6, 8, 10] 2. Using map() to Convert Data Types Example: Converting Strings to Integers string_numbers = [ "1" , "2" , "3" , "4" , "5" ] integers = list ( map ( lambda x: int (x), string_numbers)) print (integers) # Output: [1, 2, 3, 4, 5] 3. Using map() with Multiple Iterables You can also use map() with more than one iterable. The lambda function can take multiple arguments. Example: Adding Two Lists Element-wise list1 = [ 1 , 2 , 3 ]
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2 Tricky Examples Python List Comprehension

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Here are the tricky examples of list comprehension. These examples useful for your project and interviews as well.

1. Printing odd numbers

Printing odd numbers

Reminder checking logic used here. If it is not equal to zero when you divide the number with 2, it treats the input number as odd and prints it.


lst1 = [x for x in range(40) if x % 2 != 0]
print('First 20 Odd Numbers:')
print(lst1)

2. Printing even numbers

Printing even numbers

Reminder checking logic used here. If it is equal to zero when you divide the number with 2, it treats the input number as even and prints it.

lst2 = [x for x in range(40) if x % 2 == 0]
print('First 20 Even Numbers:')
print(lst2)


Output from the Python scripts

First 20 Odd Numbers: 
[1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39]


First 20 Even Numbers: 
[0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38] 


** Process exited - Return Code: 0
** Press Enter to exit terminal

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