[STATISTICS-84] Create the Mean from array input using a summation

• Type: Improvement
• Status: Closed
• Priority: Trivial
• Resolution: Implemented
• Fix Version/s: 1.1
• Component/s: descriptive
• difficulty-level: Easy
• Assignee: Unassigned
• Reporter: Alex Herbert
• Created: 05/Jan/24 09:54
• Updated: 20/Aug/24 11:07
• Resolved: 17/Jun/24 07:51

Description

The creation of the Mean from an array uses the rolling mean algorithm. This requires a divide for each input value. The algorithm is slow when compared to a simple sum of the values and a divide of the sum. The advantage is that the algorithm is overflow safe and computes the mean in a single pass (useful for streams).

In the majority of use cases a sum will not overflow. Change the array construction to attempt a sum to compute the mean, reverting to the rolling mean if this fails.