From: Paul Lutus <nospam@...>
Date: 2006-12-02T14:35:12+09:00
Subject: Re: [OT] calculations on lists of numbers

ara.t.howard@noaa.gov wrote:

> 
> for years i've felt that i should be able to pipe numerical output into
> some unix command like so
> 
>    cat list | mean
>    cat list | sum
>    cat list | minmax
> 
> etc.
> 
> and have never found one.  right now i'm building a ruby version - before
> i continue, does anyone know a standard unix or ruby version of this?

It is so easy to create in Ruby, a matter of minutes, that it is not
terribly important to do the search you are suggesting.

--------------------------------

#!/usr/bin/ruby -w

array = []

STDIN.read.split(/\s+/).each do |item|
   if(v = item.to_f)
      array << v
   end
end

if(array.size > 0)
   sum = 0
   array.each { |v| sum += v }
   mean = sum / array.size
   puts sum.to_s + " " +
     mean.to_s + " " +
     array.min.to_s + " " +
     array.max.to_s
end

--------------------------------

$ echo 1 2 3 4 5 | (script_name)

Output: 15.0 3.0 1.0 5.0

-- 
Paul Lutus
http://www.arachnoid.com