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Python 3 turn range to a list

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How do you create a list from range function in Python?

A naive method to create list within a given range is to first create an empty list and append successor of each integer in every iteration of for loop. # list until r2 is reached. We can also use list comprehension for the purpose. Just iterate 'item' in a for loop from r1 to r2 and return all 'item' as list.

Does Python range return a list?

The range() function, on the other hand, returns a list or sequence of numbers and consumes more memory than xrange() . Since the range() function only stores the start, stop, and step values, it consumes less amount of memory irrespective of the range it represents when compared to a list or tuple.


You can just construct a list from the range object:

my_list = list(range(1, 1001))

This is how you do it with generators in python2.x as well. Typically speaking, you probably don't need a list though since you can come by the value of my_list[i] more efficiently (i + 1), and if you just need to iterate over it, you can just fall back on range.

Also note that on python2.x, xrange is still indexable1. This means that range on python3.x also has the same property2

1print xrange(30)[12] works for python2.x

2The analogous statement to 1 in python3.x is print(range(30)[12]) and that works also.


In Pythons <= 3.4 you can, as others suggested, use list(range(10)) in order to make a list out of a range (In general, any iterable).

Another alternative, introduced in Python 3.5 with its unpacking generalizations, is by using * in a list literal []:

>>> r = range(10)
>>> l = [*r]
>>> print(l)
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

Though this is equivalent to list(r), it's literal syntax and the fact that no function call is involved does let it execute faster. It's also less characters, if you need to code golf :-)


in Python 3.x, the range() function got its own type. so in this case you must use iterator

list(range(1000))


The reason why Python3 lacks a function for directly getting a ranged list is because the original Python3 designer was quite novice in Python2. He only considered the use of range() function in a for loop, thus, the list should never need to be expanded. In fact, very often we do need to use the range() function to produce a list and pass into a function.

Therefore, in this case, Python3 is less convenient as compared to Python2 because:

  • In Python2, we have xrange() and range();
  • In Python3, we have range() and list(range())

Nonetheless, you can still use list expansion in this way:

[*range(N)]

You really shouldn't need to use the numbers 1-1000 in a list. But if for some reason you really do need these numbers, then you could do:

[i for i in range(1, 1001)]

List Comprehension in a nutshell:

The above list comprehension translates to:

nums = []
for i in range(1, 1001):
    nums.append(i)

This is just the list comprehension syntax, though from 2.x. I know that this will work in python 3, but am not sure if there is an upgraded syntax as well

Range starts inclusive of the first parameter; but ends Up To, Not Including the second Parameter (when supplied 2 parameters; if the first parameter is left off, it'll start at '0')

range(start, end+1)
[start, start+1, .., end]

Python 3:

my_list = [*range(1001)]

Actually, if you want 1-1000 (inclusive), use the range(...) function with parameters 1 and 1001: range(1, 1001), because the range(start, end) function goes from start to (end-1), inclusive.