Lua Running Stats Module

1. Overview

Calculates the running count, mean, variance, and standard deviation. The module is globally registered and returned by the require function.

2. Example Usage

require "streaming_algorithms.running_stats"
local stat = streaming_algorithms.running_stats.new()
for i = 1, 100 do
    stat:add(i)
end
local cnt = stat:count()
-- cnt == 100

3. Module

3.1. Functions

3.1.1. new

local rs = require "streaming_algorithms.running_stats"
local stat = rs.new()

Creates a new running_stats userdata object.

Arguments

• none

Return

• running_stats userdata object

3.2. Methods

3.2.1. add

stat:add(1.3243)

Add the value to the running stats.

Arguments

• value (number)

Return

• none

3.2.2. avg

local avg = stat:avg()

Returns the current average.

Arguments

• none

Return

• avg (number)

3.2.3. clear

stat:clear()

Resets the stats to zero.

Arguments

• none

Return

• none

3.2.4. count

local count = stat:count()

Returns the total number of values.

Arguments

• none

Return

• count (number)

3.2.5. fromstring

stat:fromstring(tostring(stat1))

Restores the stats to the previously serialized state.

Arguments

• serialization (string) tostring output

Return

• none or throws an error

3.2.6. sd

local sd = stat:sd()

Returns the current corrected sample standard deviation.

Arguments

• none

Return

• sd (number)

3.2.7. usd

local sd = stat:usd()

Returns the current uncorrected sample standard deviation.

Arguments

• none

Return

• sd (number)

3.2.8. variance

local variance = stat:variance()

Returns the current variance.

Arguments

• none

Return

• variance (number)