How Big can a Python Array Get?

Question

In Python, how big can an array/list get? I need an array of about 12000 elements. Will I still be able to run array/list methods such as sorting, etc?

Answer 1

It varies for different systems (depends on RAM). The easiest way to find out is

import six six.MAXSIZE 9223372036854775807 This gives the max size of list and dict too ,as per the documentation

Answer 2

I'd say you're only limited by the total amount of RAM available. Obviously the larger the array the longer operations on it will take.

Answer 3

Sure it is OK. Actually you can see for yourself easily:

l = range(12000)
l = sorted(l, reverse=True)

Running the those lines on my machine took:

real    0m0.036s
user    0m0.024s
sys  0m0.004s

But sure as everyone else said. The larger the array the slower the operations will be.

Answer 4

In casual code I've created lists with millions of elements. I believe that Python's implementation of lists are only bound by the amount of memory on your system.

In addition, the list methods / functions should continue to work despite the size of the list.

If you care about performance, it might be worthwhile to look into a library such as NumPy.