module Benchmark

Create a plot of the benchmarked code over a varied number of inputs.

@param test_data [Enumerable] An object containing the data that is to be

used for the benchmarking. This object must be Enumerable, i.e. it must
have the `#each` method defined. Each of the constituent objects of 
`test_data` should have a `#to_s` method defined, which will be used for
populating the X axis labels.

@param [Hash] opts The options for configuring the graph. @option opts [Symbol, String] :title (:Benchmarks) Title of the graph. @option opts [Symbol, String] :file_name (:benchmark_plot_graph) Name of

file to which plot is written.

@option opts [Symbol] :time (:real) The kind of time that should be displayed

on the graph. Can be `:real` for elapsed real time, `:stime` for System 
CPU time, `:utime` for User CPU time, `:cstime` for System CPU time of children,
`:cutime` for User CPU time of children, and `:total` for the total time
that is `:utime + :stime + :cutime + :cstime`.

@option opts [TrueClass, FalseClass] :x_labels (true) Whether you want X-axis

labels or not.

@option opts [String, Symbol] :x_axis_label (nil) X-axis label string. @example Benchmark map{}.flatten vs. flat_map

require 'benchmark/plot'
class TestArray
   attr_reader :arr

   def initialize arr
     @arr = arr
   end

   # The to_s method is called for populating the X axis labels.
   def to_s
     @arr.size.to_s
   end
 end

 test_data = [5, 25, 50, 75, 100, 125, 150, 175, 200,250,300]
 test_data.map! {|e| TestArray.new(Array.new(e) {|i| i}) }

 Benchmark.plot(test_data) do |x|
   x.report("map.flatten") do |data|
      # Here `data` will be of an object of type `TestArray`.
     data.arr.map { [nil]  }.flatten
   end

  x.report("flat_map") do |data|
    data.arr.flat_map { [nil] }
  end
end

# File lib/benchmark/plot.rb, line 56
def self.plot test_data, opts={}, &block
  include Benchmark::Plot

  reporter = ReportMaker.new(test_data)
  yield(reporter)
  plotter = Plotter.new reporter, test_data, opts
  plotter.plot
end