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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 Unpack a List into Variables Quickly in Python

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Here are two examples to unpack a list in Python. You can do it easily by using splat operator. The asterisk in python is called a Splat operator. Here are two splat operators - Single and Double. Below, you will find examples.

1. Single splat operator


Consider, for example, this code:
abc = [1,2,3,4]
print(abc) 

Here the output will be: [1, 2, 3, 4]

What if you didn't want the list output in list format? What if all you wanted was the list of values to be written to the output console? You could write them using a loop and one of the output functions, but Python prefers an easier way:

print(*abc) 1 2 3 4


Unpack List Splat Operators



2. Double splat operator

Here, I have written a function:

def func(x,y,z): 
      return x + y + z

print(func(**d))

It will show '6' as output. Since, I have assigned values for x,y, and z in a dictionary. So by using a double splat operator you assign values to the function.

d = { 
'x': 1, 
'y': 2, 
'z': 3 
}


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