Why does “x = x.append(…)” not work in a for loop?

append actually changes the list. Also, it takes an item, not a list. Hence, all you need is

for i in range(n):
   list1.append(i)

(By the way, note that you can use range(n), in this case.)

I assume your actual use is more complicated, but you may be able to use a list comprehension, which is more pythonic for this:

list1 = [i for i in range(n)]

Or, in this case, in Python 2.x range(n) in fact creates the list that you want already, although in Python 3.x, you need list(range(n)).

Leave a Comment