Class: Array

Inherits:
Object
  • Object
show all
Defined in:
lib/sysadmin/array_ext.rb

Overview

Name

Sysadmin::ArrayExtension

Author

774 <id774.net>

Created

Aug 20, 2013

Updated

Aug 20, 2013

Copyright

774 Copyright © 2013

License

Licensed under the GNU GENERAL PUBLIC LICENSE, Version 3.0.

Instance Method Summary collapse

Instance Method Details

#average ⇒ Object 



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# File 'lib/sysadmin/array_ext.rb', line 10

def average
  inject(0.0) { |sum, i| sum += i } / size
end

#standard_devitation ⇒ Object 



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# File 'lib/sysadmin/array_ext.rb', line 19

def standard_devitation
  Math::sqrt(self.variance)
end

#variance ⇒ Object 



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# File 'lib/sysadmin/array_ext.rb', line 14

def variance
  ave = self.average
  inject(0.0) { |sum, i| sum += (i - ave)**2 } / size
end