Module: StatisticalMethods
- Included in:
- Array
- Defined in:
- lib/ruby-technical-analysis/statistical_methods.rb
Overview
Statistical methods used in calculations
Instance Method Summary collapse
Instance Method Details
#standard_deviation ⇒ Object
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# File 'lib/ruby-technical-analysis/statistical_methods.rb', line 5 def standard_deviation if size <= 1 raise ArgumentError, "Array must contain at least 2 numbers for standard deviation." end mean = reduce(:+).to_f / size sq_dist = 0 each do |n| sq_dist += (n - mean).abs2 end Math.sqrt(sq_dist.to_f / size) end |