Calculate an average value
We all know how to calculate an average value iteratively:
def average(nums):
result = 0
for num in nums:
result += num
return result/len(nums)
Could you provide a recursive solution? A formula for updating an average value given a new input might be handy:
$$ \bar{x} \leftarrow \frac{x_i + (n-1)\bar{x}}{n} $$
Here, \(\bar x\) stands for an average value, \(x_i\) is a new supplied value which is used to update the average, and \(n\) corresponds to the recursive call number (excluding the initial call to the function).
Este exercício faz parte do curso
Practicing Coding Interview Questions in Python
Instruções do exercício
- Provide the base case for the algorithm.
- Define the recursive call for updating the average value.
Exercício interativo prático
Experimente este exercício completando este código de exemplo.
# Calculate an average value of the sequence of numbers
def average(nums):
# Base case
if len(nums) == ____:
return ____[____]
# Recursive call
n = len(nums)
return (____ + ____ * ____) / ____
# Testing the function
print(average([1, 2, 3, 4, 5]))