Python Recursion error - Printable Version

[Python] Recursion error - Printable Version

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Recursion error - Sentience - Jul 16, 2022

This gives me a recursion error:

Code 
def f(n: int) -> bool:

 return f(n) >= f(n+1)

How can I write this so it runs?

Thanks,
Oliver

RE: Recursion error - SIM-574702 - Jul 16, 2022

Funtion f is defined with int parameter so you can call it with f(0) or any other integer. If you really want to call it as f(n) you need to define n.

Code 
n=0

f(n)

I'm not sure what you're trying to do but this will always give you maximum recursion depth exceeded because you don't have an exit condition.

RE: Recursion error - Athr - Jul 16, 2022

(Jul 16, 2022 03:16 PM)Sentience Wrote: This gives me a recursion error:

Code
def f(n: int) -> bool: return f(n) >= f(n+1)
This says n is undefined:

Code
f(n)

How can I write this so it runs?

Thanks,
Oliver

You have not defined n before calling the function.
Write the following line to define n.

Code 
#Sample n value

n = 5

print(f(n))

EDIT:

SIM-574702 is right about the exit condition.
Its like a base case for an induction problem in math.

RE: Recursion error - Sentience - Jul 18, 2022

Code 
# We represent elements of N_∞ as functions f : int -> bool, where we only care about

# the values of those functions for nonnegative inputs n, and the functions are

# assumed to satisfy f(n) >= f(n+1) for all n >= 0.

This is an excerpt of what I am talking about

It’s not supposed to call itself…

How can I write this:

Code 
def f(n: int) -> bool:

return f(n) >= f(n+1)

Without recursion?

Edit: Solved…

Code 
def g(f: typing.Callable[[int], bool], n: int) -> bool:

 return f(n) >= f(n + 1)

RE: Recursion error - Sentience - Jul 19, 2022

Wait wtf how do call g()?

Turns out I can call g just by going

g

RE: Recursion error - SIM-4763645 - Jul 25, 2022

```
def f():
def g():
f()
# then call g() inside main thread
```

RE: Recursion error - Sentience - Jul 25, 2022

(Jul 19, 2022 10:26 AM)Sentience Wrote: Wait wtf how do call g()?

Turns out I can call g just by going

g

Edit: This thread is solved