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Compute Mean and Standard Deviation
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Compute Mean and Standard Deviation

EasyPython

Problem

At Acme Analytics, you need a utility function that summarizes a list of numeric values. Write a function that returns the mean and population standard deviation of a list of numbers.

The mean is the sum of all values divided by the number of values. The population standard deviation is defined as sqrt(sum((x - mean)^2) / n).

Function Specification

  • Input: a list nums of integers or floating-point numbers
  • Output: a list of two numbers: [mean, standard_deviation]

If the input list is empty, return [0, 0].

Constraints

  • 0 <= len(nums) <= 10^5
  • -10^6 <= nums[i] <= 10^6
  • Input values may be integers or floating-point numbers
  • Return the population standard deviation using sqrt(sum((x - mean)^2) / n)
  • Answers within a small floating-point tolerance are acceptable

Function Signature

def mean_and_stddev(nums):
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