irb(main):001:0> require 'ai4r'
=> true
irb(main):002:0> train = [[1,2,3],[2,3,4],[3,4,5]]
=> [[1, 2, 3], [2, 3, 4], [3, 4, 5]]
irb(main):003:0> labels = ["one", "two", "three"]
=> ["one", "two", "three"]
irb(main):004:0>  data_set = DataSet.new(:data_items=>train, :data_labels=>labels)
NameError: uninitialized constant DataSet
	from (irb):4
	from /home/vishwa/.rbenv/versions/2.2.0/bin/irb:11:in `<main>'
irb(main):005:0>  data_set = ai4r::Data::DataSet.new(:data_items=>train, :data_labels=>labels)
NameError: undefined local variable or method `ai4r' for main:Object
	from (irb):5
	from /home/vishwa/.rbenv/versions/2.2.0/bin/irb:11:in `<main>'
irb(main):006:0>  data_set = Data::DataSet.new(:data_items=>train, :data_labels=>labels)
NameError: uninitialized constant Data::DataSet
	from (irb):6
	from /home/vishwa/.rbenv/versions/2.2.0/bin/irb:11:in `<main>'
irb(main):007:0>