This is a simple package that generates simple statistical info on numerical data sets of a single variable. It's nothing too fancy, but maybe just enough to coat your numbers with a thin layer of science. Or, at least to get you thinking about what it may take to do so.
It's small and simple
It's probably good enough
I haven't profiled it against large data sets
Naive median implementation requires a sort, but it could be done in linear time. Patches welcome.
Missing tests for harmonic and geometric mean – the stats package I was generating test data with didn't have them.
require 'ministat' data = [1,2,3,4,5,6,7,7,6,5,4,4] d = MiniStat::Data.new(data) d.median # => 4.5 d.mean # => 4.5 d.mode # => 4.0 d.q1 # => 3.5 d.outliers # =>  d.std_dev # => 1.80277563773199 # and so on... puts MiniStat::Data.new(data).to_s # this outputs most everything
Hoe is your friend.
sudo gem install ministat
(The MIT License)
Copyright © 2007-2010 Dean Hudson
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