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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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How to Delete an Item from a Set in Python: Best Example

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Set is a built-in data type in Python. Furthermore, it is an unordered collection without duplicate items. Here are the two methods that explain to delete an item from a Set.

Methods to delete an item from a Set

  • discard
  • remove



Discrd Vs. Remove


  • discard() will not raise an error if the item to remove does not exist.
  • The remove() will raise an error if the item does not exist.


Remove items from Set


Explanation to discard and remove methods


Python program:

#Prints all the Set items

food = {"pasta", "burger", "hot dog", "pizza"}

print(food)


# Prints the Set items without pasta

food.discard("pasta")

print(food)


# Prints the Set items without burger and pasta

food.remove("burger")

print(food)


# The next two lines try to remove an item that isn't in the set!

food.discard("pasta")  # this will not report an error

food.remove("pasta")   # this will report an error


The output:

{'pasta', 'burger', 'pizza', 'hot dog'}

{'burger', 'pizza', 'hot dog'}

{'pizza', 'hot dog'}

Traceback (most recent call last):

  File "main.py", line 12, in <module>

    food.remove("pasta")   # this will report an error

KeyError: 'pasta'


** Process exited - Return Code: 1 **

Press Enter to exit terminal


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