Add bin and edit workflow

bin/gems/facets-3.1.0/lib/standard/facets/math/rmd.rb

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+require 'facets/math/approx_equal'
+
+module Math
+
+  # Calculates the relative mean difference of this sample.
+  # Makes use of the fact that the Gini Coefficient is half the RMD.
+  def self.rmd(array)
+    return 0.0 if approx_equal(mean(array), 0.0)
+    gini_coefficient(array) * 2
+  end
+
+  class << self
+    alias_method  :relative_mean_difference, :rmd
+  end
+
+end