Class: RailsDataExplorer::Statistics::RngCategory

Inherits:
Object
  • Object
show all
Defined in:
lib/rails_data_explorer/statistics/rng_category.rb

Overview

Responsibilities:

* Provide random categorical data. Useful for testing and demo data.

Instance Method Summary collapse

Constructor Details

#initialize(categories, category_probabilities = nil, rng = lambda { Kernel.rand }) ⇒ RngCategory

Returns a new instance of RngCategory.

Parameters:

  • categories (Array<Object>) —

    the pool of available categories.

  • category_probabilities (Array, optional) (defaults to: nil) —

    probability of each category.

  • rng (Proc, optional) (defaults to: lambda { Kernel.rand }) —

    lambda to generate random numbers which will be mapped to categories.



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# File 'lib/rails_data_explorer/statistics/rng_category.rb', line 15

def initialize(categories, category_probabilities = nil, rng = lambda { Kernel.rand })
  @categories, @category_probabilities, @rng = categories, category_probabilities, rng
  @category_probabilities ||= @categories.map { |e| @rng.call }
  @category_probabilities = normalize_category_probabilities
  @category_order = compute_category_order
end

Instance Method Details

#rand ⇒ Object

Returns a random category



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# File 'lib/rails_data_explorer/statistics/rng_category.rb', line 23

def rand
  r_v = @rng.call
  rnd = @category_order.detect { |e|
    e[:threshold] >= r_v
  }
  rnd[:category]
end