Input array containing numerical values.
result: A double representing the computed mean of the input array.
Notes: - The function assumes array_IN is not empty; otherwise, a division by zero will occur. - The arithmetic mean is calculated as the sum of all elements divided by the number of elements. - If working with large datasets, be mindful of potential floating-point precision issues. - If array_IN contains extreme values, consider using a robust mean estimator (e.g., median or trimmed mean).
Summary: Computes the arithmetic mean (average) of an input array.