how to create list with index in name in python

Question

I it possible in python to create a set of lists with index i in the name?

for i in range(0,5):
    list_i = []  # here i should change according to index i

I would like to create 5 lists with names: list_0, list_1 ... _list_4 and the append something to these lists.

possible duplicate of [How do I do variable variables in Python?](http://stackoverflow.com/questions/1373164/how-do-i-do-variable-variables-in-python) — Morgan Thrapp, Aug 07 '15 at 16:24

score 2 · Accepted Answer · answered Aug 07 '15 at 16:10

2

Just use a dictionary of lists.

results_dict = {}
for i in range(5):
    results_dict[i] = []

answered Aug 07 '15 at 16:10

Morgan Thrapp

ok thanks a lot, so it is only possible with dictionary ... I thought that there's another way how to create a list from a string maybe ... – user3041107 Aug 07 '15 at 16:20
1

There are some super hacky methods to use dynamic variable names, but there's no reason to use them. It's much easier/readable to just use a dictionary. – Morgan Thrapp Aug 07 '15 at 16:21

AmirC · Answer 2 · 2015-08-07T17:09:44.480

1

It might not be very straightforward, but I don't call this super hacky though. It is quite useful in some cases to use dynamic naming.

for i in range(5):
    vars()['list_%d'%i] = i

print(list_1)
print(list_2)
print(list_3)
print(list_4)

List Version

for i in range(5):
    vars()['list_%d'%i] = [i, i+1]

print(list_1)
print(list_2)
print(list_3)
print(list_4)

edited Aug 07 '15 at 17:09

answered Aug 07 '15 at 17:05

AmirC

Does this work if `vars()['list_%d' %i] = []`? In other words, initializing to an empty list like the OP's question? – Engineero Aug 07 '15 at 17:08

2 Answers2