Vendor unreleased rack-mount 0.6.6.pre dependency

1 files changed, 74 insertions, 0 deletions

diff --git a/actionpack/lib/action_dispatch/vendor/rack-mount-0.6.6.pre/rack/mount/analysis/histogram.rb b/actionpack/lib/action_dispatch/vendor/rack-mount-0.6.6.pre/rack/mount/analysis/histogram.rb
new file mode 100644
index 0000000000..20aaa132f9
--- /dev/null
+++ b/actionpack/lib/action_dispatch/vendor/rack-mount-0.6.6.pre/rack/mount/analysis/histogram.rb
@@ -0,0 +1,74 @@
+module Rack::Mount
+  module Analysis
+    class Histogram < Hash #:nodoc:
+      attr_reader :count
+
+      def initialize
+        @count = 0
+        super(0)
+        expire_caches!
+      end
+
+      def <<(value)
+        @count += 1
+        self[value] += 1 if value
+        expire_caches!
+        self
+      end
+
+      def sorted_by_frequency
+        sort_by { |_, value| value }.reverse!
+      end
+
+      def max
+        @max ||= values.max || 0
+      end
+
+      def min
+        @min ||= values.min || 0
+      end
+
+      def mean
+        @mean ||= calculate_mean
+      end
+
+      def standard_deviation
+        @standard_deviation ||= calculate_standard_deviation
+      end
+
+      def upper_quartile_limit
+        @upper_quartile_limit ||= calculate_upper_quartile_limit
+      end
+
+      def keys_in_upper_quartile
+        @keys_in_upper_quartile ||= compute_keys_in_upper_quartile
+      end
+
+      private
+        def calculate_mean
+          count / size
+        end
+
+        def calculate_variance
+          values.inject(0) { |sum, e| sum + (e - mean) ** 2 } / count.to_f
+        end
+
+        def calculate_standard_deviation
+          Math.sqrt(calculate_variance)
+        end
+
+        def calculate_upper_quartile_limit
+          mean + standard_deviation
+        end
+
+        def compute_keys_in_upper_quartile
+          sorted_by_frequency.select { |_, value| value >= upper_quartile_limit }.map! { |key, _| key }
+        end
+
+        def expire_caches!
+          @max = @min = @mean = @standard_deviation = nil
+          @keys_in_upper_quartile = nil
+        end
+    end
+  end
+end