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Using recursion instead of for loops / list comprehension
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Using recursion instead of for loops / list comprehension
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So I’ve been learning about symmetric differences between lists which can be accomplished in a number of different ways using for loops, list comprehension, sets the exclusive or carat. Pretty neat stuff

Now I am exploring recursion. Wrapping my head around this programming concept is difficult because it’s like a whole different paradigm. Haskell apparently doesn’t have any loops. If you need to iterate over a list, Haskell programmers call a function from within a function. w3schools address function recursion in Python and so does programiz using factorials as an example but the sample code in both tutorials escape my understanding.

Could someone here re-write the for loops (below) but using recursion?

Say I want to create a list of multiples of 2 up to 16. Here is the desired output: 
Quote:[0, 4, 8, 12, 16]

There are many ways of doing this in Python. Here are two:

>>> S = [2*n for n in range(0,9) if ( (n % 2) == 0)]
>>>print(S)
And:

>>> def multiples_of_four(n):
...     newlist = []
...     for n in range(0,n*2):
...         if n % 4 == 0:
...              newlist.append(n)
...     return newlist
...
>>> multiples_of_four(9)
That’s great. But how might experienced Python developers such as all of you achieve the same output but by using recursion?
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Messages In This Thread
Using recursion instead of for loops / list comprehension - by Drone4four - Oct-10-2020, 03:40 AM

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