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I have been trying to figure out a clear and concise method to iterate through elements in a list in a form of recursive loop.

For example, if I have a list:

My_list = [2, 4, 6, 8, 10, 12, 14, 16, 18, 20]

I would like to extract every other element from the list.

New_list = [2, 6, 10, 14, 18]

I then want to take the discarded values and take every second of those. And so on, recursively.

Since my first run through the list ended at 18, I will skip over 20 and go back to the beginning of the list as I want to extract every other elements.

My_list = [2, 4, 6, 8, 10, 12, 14, 16, 18, 20]

# Elements not been used after first operation = [4, 8, 12, 16, 20]

New_list = [2, 6, 10, 14, 18, 4, 12, 20, 8, 16] # desired output

What methods can I use to loop within a list?

Yes, you can use a while loop with a generator:

L = [2, 4, 6, 8, 10, 12, 14, 16, 18, 20]

def recursive_odds(x):
 while x:
 yield from x[::2]
 x = x[1::2]

res = list(recursive_odds(L))

[2, 6, 10, 14, 18, 4, 12, 20, 8, 16]

you can use python's really cool slicing syntax:

new_list=my_list[::2]

to get every other element.

It means new_list is my_list from the begining to the end with a stride of 2

then your ramainder elements are elements_not_used = [item for item in my_list if item not in new_list] and you can just continue until len(my_list)<2

using while loop you can do this:

final=
while len(mylist)>0:
 final.extend(mylist[::2])
 mylist=mylist[1::2]
print(final)