Method: Utilities::Statistics#standard_deviation

Defined in:
lib/utilities/utilities.rb

#standard_deviation(population = false) ⇒ Object Also known as: std_dev

Return the (sample|population) standard deviation of self If population is set to true, then we consider the dataset as the complete population Else, we consider the dataset as a sample, so we use the sample standard deviation (size - 1)



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# File 'lib/utilities/utilities.rb', line 73

def standard_deviation( population = false )
  return nil if empty?
  size > 1 ? Math.sqrt( variance( population ) ) : 0.0
end