Feature #2322: [PATCH] Add standard deviation function to Math Module

• Status: Rejected
• Assignee: mrkn (Kenta Murata)
• Target version: 2.0.0

[danielc192 (Daniel Cohen)]

=begin
This patch adds a Standard Deviation function to the Math Module. It takes an array and finds the standard deviation of all its elements, as long as they are numbers.
=end

[znz (Kazuhiro NISHIYAMA)]

• Target version set to 2.0.0

=begin

=end

[nahi (Hiroshi Nakamura)]

• Description updated (diff)
• Assignee set to mrkn (Kenta Murata)

[shyouhei (Shyouhei Urabe)]

• Status changed from Open to Assigned

[mrkn (Kenta Murata)]

• Status changed from Assigned to Rejected

Why do we need to specially treat the 2nd central moment, that is standard deviation, than the other nth moment, such as skewness (3rd) and kurtosis (4th)?

You can use NArray for that reason. See http://narray.rubyforge.org/index.html.en