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Rolling Metrics on Streams
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Rolling Metrics on Streams

MediumPython

Problem

Implement an efficient solution using the sliding window pattern to compute rolling performance metrics on real-time data streams.

Given an ordered list of numeric measurements and a positive window size, return the average of every complete consecutive window in order. The function must avoid recomputing each window from scratch.

Signature: def rolling_average(measurements, window_size). Return a list of floating-point averages. For example, [2, 4, 6, 8] with window 2 returns [3.0, 5.0, 7.0].

Constraints

  • 1 <= window_size <= len(measurements)
  • 1 <= len(measurements) <= 100000
  • -10^9 <= measurements[i] <= 10^9
  • Measurements are ordered by arrival time
  • Return one average for every complete window

Function Signature

def rolling_average(measurements, window_size):
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