@@ -1,9 +1,24 @@ -= ar_std += standard_deviation Adds standard deviation methods to ActiveRecord. sqlite does not include standard deviation methods by default, so this is designed for mysql only. +== Installation + + ./script/plugin install git://github.com/jmckible/standard_deviation.git + + +== Usage + +This plugin adds two new aggregations methods to ActiveRecord: std and variance. Say you've got a measurements table with an integer column called 'integer.' + + Measurement.std(:integer) + # => 0.8165 + Measurement.variance(:integer) + # => 0.6667 + + == Author -* ar_std was created by Jordan McKible http://jordan.mckible.com +* standard_deviation was created by Jordan McKible http://jordan.mckible.com -* Available on GitHub at http://github.com/jmckible/ar_std \ No newline at end of file +* Available on GitHub at http://github.com/jmckible/standard_deviation \ No newline at end of file README.rdoc f5c2186f3609a111da1cd1378a7ca30829a2eb0b Jordan McKible jordan@mckible.com http://github.com/jmckible/standard_deviation/commit/a55b688e010c68da423a3930f22d3ca7a87d4eb4 a55b688e010c68da423a3930f22d3ca7a87d4eb4 2009-10-02T13:59:33-07:00 2009-10-02T13:59:33-07:00 Update README. ec16c91bfc294f50fb3f21194b9cb9fe61cac1ad Jordan McKible jordan@mckible.com