Posted By: Anonymous
I have this tail recursive function here:
def recursive_function(n, sum): if n < 1: return sum else: return recursive_function(n-1, sum+n) c = 998 print(recursive_function(c, 0))
It works up to
n=997, then it just breaks and spits out a
RecursionError: maximum recursion depth exceeded in comparison. Is this just a stack overflow? Is there a way to get around it?
It is a guard against a stack overflow, yes. Python (or rather, the CPython implementation) doesn’t optimize tail recursion, and unbridled recursion causes stack overflows. You can check the recursion limit with
import sys print(sys.getrecursionlimit())
and change the recursion limit with
but doing so is dangerous — the standard limit is a little conservative, but Python stackframes can be quite big.
Python isn’t a functional language and tail recursion is not a particularly efficient technique. Rewriting the algorithm iteratively, if possible, is generally a better idea.