## Fibonacci with Python: IndexError: list index out of range

I was trying to write a program to compute the Fibonacci number using Python:

n = int(input()) def fib(n): a = [] if (n <=1): return n else: for i in range(2, n): a.append(a[-1] + a[-2]) return a[i] print (fib(n))

However, I can't print out the expected result. For example, after I typed in the number 8, the following message popped up:

Traceback (most recent call last): File "fibonacci.py", line 11, in <module> print (fib(n)) File "fibonacci.py", line 9, in fib a.append(a[-1] + a[-2]) IndexError: list index out of range

What went wrong in the process? Thanks in advance.

You need to populate your list with first 2 numbers of Fibonacci sequence:

a = [0, 1]

**How is this list index out of range? (Fibonacci numbers exercice ,** You are looping over the values not the index positions! Use the following code instead: #Creates a list with the first ten Fibonacci numbers. l� IndexError: list index out of range. The first age, 9, is printed to the console. However, the value of “age” is an actual value from “ages”. It’s not an index number. On the “print (ages [age])” line of code, we’re trying to access an age by its index number. When we run our code, it checks for: ages [9].

-2 and -1 indexes are not available if you don't set them in "a" list before using.

n = int(input()) def fib(n): a = [0, 1] if n <=1: return n else: for i in range(2, n): a.append(a[-1] + a[-2]) return a[i] print (fib(n))

**How is this list index out of range? (Fibonacci numbers - Python,** list with all even Fibonacci numbers. print sum(l) When I execute this I get: File " pe2m.py", line 6, in <module> if l[i]%2 != 0: IndexError: list index out of range I� An index is a location of an item in an Array or a List and in most of the programming language, it starts from 0. So when we count the elements in a list, we’ll count them from 1 but when we’ll try to access the elements of the list, we’ll start our index from 0.

Make these changes in your code

n = int(input()) def fib(n): a = [0,1] # add these values to your array to intialize if (n <=1): return n else: for i in range(2, n): a.append(a[-1] + a[-2]) return a # change this also so that you can get all the values returned at the same time print (fib(n))

***** IndexError: list index out of range Code Example,** “*** IndexError: list index out of range” Code Answer. *** IndexError: list index out of range. python by Dr. Hippo on Apr 08 2020 Donate. This piece of code throws the error: IndexError: list index out of range. Let me know if it is even possible to generate such a series using a list comprehension. python list-comprehension fibonacci

Call this function to compute any Fibonacci series number

def Fibonacci(n): if n<0: print("Incorrect input") # First Fibonacci number is 0 elif n==0: return 0 # Second Fibonacci number is 1 elif n==1: return 1 else: return Fibonacci(n-1)+Fibonacci(n-2)

Or you can use this formula the formula for nth term in the fibonacci series.

Fn = {[(√5 + 1)/2] ^ n} / √5

**how to fix list index out of range in python Code Example,** Get code examples like "how to fix list index out of range in python" instantly IndexError: list assignment index out of range pygame meaning � python array� But in case you mention an index in your code that is outside the range of the list, you will encounter an IndexError. “ List index out of range ” error occurs in Python when we try to access an undefined element from the list. The only way to avoid this error is to mention the indexes of list elements properly.

**Python indexerror: list index out of range Solution,** On Career Karma, learn about the Python indexerror: list index out of range error, how the error works, and how to solve the error. List elements can be modified and assigned new value by accessing the index of that element. But if you try to assign a value to a list index that is out of the list’s range, there will be an error. You will encounter an IndexError list assignment index out of range. Suppose the list has 4 elements and you are trying to assign a value into the 6th position, this error will be raised.

**11. Recursion and exceptions — How to Think Like a Computer ,** One of the differences we noted is that the elements of a list can be modified, but the Python provides a form of tuple assignment that solves this problem neatly: recent call last): File "<stdin>", line 1, in <module> IndexError: list index out of range >>> Another well know recursive relation in mathematics is the fibonacci � Python: IndexError: list index out of range. Ask Question Asked 8 years, 6 months ago. Active 3 months ago. IndexError: list index out of range

**Help with IndexError: list assignment index out of range (Array help ,** Please look at the fibonacci solution over at r/Python on the sidebar. It is quite elegant and a full use of the power of the Python's generators. The index existed at the start of the loop, but once you have deleted an element, the list is shorter, and does not contain the same number of elements. Thus, your indices may be wrong. If you delete from the end of the list forward, that won't invalidate list indices.

##### Comments

- How to debug small programs
`IndexError: list index out of range`

your'e starting out with an empty array and trying to access index's on it.