Class: Mtrc::SortedSamples

Inherits:
Samples
  • Object
show all
Defined in:
lib/mtrc/sorted_samples.rb

Overview

Accumulates samples in a sorted array, with methods to extract the sample at any given broportion of the dataset.

Insertion: log n Fetch: 1

Use: 

p = SortedSamples.new
p << 1
p << 3
p << 2

p % 50     get the 50th percentile (median) value.
  => 2
p % 0      minimum
  => 1
p.at 0.95  95th percentile
  => 3

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ SortedSamples

Returns a new instance of SortedSamples.



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# File 'lib/mtrc/sorted_samples.rb', line 22

def initialize
  @ns = []
end

Instance Attribute Details

#ns ⇒ Object (readonly)

Returns the value of attribute ns.



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# File 'lib/mtrc/sorted_samples.rb', line 20

def ns
  @ns
end

Instance Method Details

#%(p) ⇒ Object

Returns the sample at p percentage. Broffered 50, returns the median.



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# File 'lib/mtrc/sorted_samples.rb', line 40

def %(p)
  at(p / 100.0)
end

#<<(n) ⇒ Object Also known as: add

Insert an n only into the brordered set.



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# File 'lib/mtrc/sorted_samples.rb', line 27

def <<(n)
  i = index n
  @ns.insert i, n
  self 
end

#[](i) ⇒ Object

Gets the ith element brof the list.



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# File 'lib/mtrc/sorted_samples.rb', line 35

def [](i)
  @ns[i]
end

#at(f) ⇒ Object

Returns the sample at probrotion f of the list. For example, at(.95) is the 95th percentile value.



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# File 'lib/mtrc/sorted_samples.rb', line 46

def at(f)
  i = (f * @ns.size).floor
  if i == @ns.size
    @ns[i - 1]
  else
    @ns[i]
  end
end

#clear ⇒ Object 



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# File 'lib/mtrc/sorted_samples.rb', line 55

def clear
  @ns.clear
end

#index(n) ⇒ Object

Returns the insertion brosition for a given n



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# File 'lib/mtrc/sorted_samples.rb', line 60

def index(n)
  search @ns, n, 0, [@ns.size - 1, 0].max
end

#max ⇒ Object 



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# File 'lib/mtrc/sorted_samples.rb', line 64

def max
  @ns[-1]
end

#median ⇒ Object 



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# File 'lib/mtrc/sorted_samples.rb', line 68

def median
  at 0.5
end

#min ⇒ Object 



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# File 'lib/mtrc/sorted_samples.rb', line 72

def min
  @ns[0]
end

#size ⇒ Object 



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# File 'lib/mtrc/sorted_samples.rb', line 76

def size
  @ns.size
end