Double Index Code Challenge question


#1

Regarding this exercise:

Create a function named double_index that has two parameters named lst and index .

The function should double the value of the element at index of lst and return the new list with the doubled value.

If index is not a valid index, the function should return the original list.

(https://www.codecademy.com/paths/data-science/tracks/dspath-python-lists-and-loops/modules/dspath-lists/lessons/python-functions-lists-cc/exercises/double-index)

#Write your function here
def double_index(lst, index):
if index < len(lst):

   I DON'T UNDERSTAND THIS LINE IN THE SOLUTION:
   lst[index] = lst[index] * 2

return lst

#Uncomment the line below when your function is done
print(double_index([3, 8, -10, 12], 3))

HOW CAN SOMETHING BE SET TO EQUAL ITSELF TIMES 2? SEEMS LIKE THERE SHOULD BE A CLEARER WAY TO REPRESENT THIS? THANKS.


#2

it can’t, but in programming a single equal sign (=) means assign. It doesn’t mean set equal to. So we get the value from lst at index, multiple it by 2, and store it in the list again.


#3

Thanks for the reply. That helps.