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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 Write Recursive Function in Python Quickly

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Here's an example to write RECURSIVE function in Python. It acts like a loop that iterate within the function to perform some operation. Precisely, if you call the same function from function is called recursive function.  
 

Recursion in Python


Python recursive function

Here are four rules a developer should know before writing recursive function in Python:

  1. There must be a key variable, which will be responsible for the termination of recursion.
  2. To determine the base value, which the key variable has to meet to reach the termination.
  3. To make sure the key variable must approach the base value in every recursive call.
  4. To make the recursive function terminate when the key variable reaches the base value.


Python recursive example


Here is an example python recursive function.

# This program computes the factorial of a number using recursion
#function definition
def fact(n):
"computes factorial using recursion"
if n == 0:
    return 1
else :
    return n * fact(n - 1)

# Function call
num = input("enter a number:")
num = int(num)
result = fact(num)
print("factorial=", result)


Advantages


Here are the advantages of recursive function.
  • Recursive functions divide the problem into smaller similar fragments and then computes them.
  • The recursive code looks precise and cleaner as compared to using loops. Here is how to call SQL from python

Disadvantages


Here are the disadvantages of recursive function.
  • It's hard to develop
  • Its is hard to understand the recursive functions

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