Module: ArrayFastMethods

Included in:
Array
Defined in:
lib/array_fast_methods.rb,
lib/array_fast_methods/version.rb

Constant Summary collapse

VERSION = 
"0.1.1"

Instance Method Summary collapse

Instance Method Details

#mean ⇒ Object 



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# File 'lib/array_fast_methods.rb', line 5

def mean
  (sum.to_f / size.to_f)
end

#std_dev ⇒ Object 



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# File 'lib/array_fast_methods.rb', line 16

def std_dev
  Math.sqrt(variance)
end

#variance ⇒ Object 



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# File 'lib/array_fast_methods.rb', line 9

def variance
  m = mean
  sum_let = 0.0
  each {|v| sum_let += (v-m)**2 }
  sum_let/size
end