average: Compute the mean and standard deviation of a list

Package: lists

Usage

average option

Parameters

option

Chosen from "add", "subtract" or "new_sample", in which case the numbers averaged are those in STDIN. If no argument is given on the command line, "new_sample" is assumed.

Description

Task average computes the average and standard deviation of a list of numbers. Numeric input is read from STDIN with one number per line. The mean, sigma and number of samples are written to the standard output.

By default, the sample is taken to be the set of numbers in the standard input when average is run. Additional points can be added to or deleted from the sample by rerunning average with option equal to one of the following:

add

add points to the sample, recalculate mean and sigma

sub

subtract points from the sample

The sample is reinitialized by setting option = "new_sample".

Examples

Run average on the list of numbers in file "numbers".

cl> type numbers | average

Add in to the sample the list of numbers in file "numbers.2".

cl> average add < numbers.2

See also

lintran