Class: Statkit::Spec::StdevFuncExp

Inherits:
BaseExp
  • Object
show all
Defined in:
lib/statkit/specexp.rb

Instance Method Summary collapse

Methods inherited from BaseExp

#add_input

Constructor Details

#initialize ⇒ StdevFuncExp

Returns a new instance of StdevFuncExp.



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# File 'lib/statkit/specexp.rb', line 48

def initialize
  @nr_input = 0
  @sum = 0
  @sum_sq = 0
end

Instance Method Details

#add_input_chunk(input_chunk) ⇒ Object 



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# File 'lib/statkit/specexp.rb', line 58

def add_input_chunk(input_chunk)
  input_chunk.each do |val|
    @nr_input += 1
    @sum += val
    @sum_sq += val ** 2
  end
end

#evaluate ⇒ Object 



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# File 'lib/statkit/specexp.rb', line 66

def evaluate()
  var = @sum_sq / @nr_input.to_f - (@sum / @nr_input.to_f)**2
  Math.sqrt(var) * Math.sqrt(@nr_input / (@nr_input.to_f - 1))
end

#streaming? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/statkit/specexp.rb', line 54

def streaming?
  true
end