examples/histogram.rb in statsample-1.5.0 vs examples/histogram.rb in statsample-2.0.0

@@ -1,12 +1,26 @@
 #!/usr/bin/ruby
 $:.unshift(File.dirname(__FILE__)+'/../lib/')
+
+# == Description
+# 
+# This example demonstrates how a histogram can be created 
+# with statsample.
+# 
+# The 'histogram' function creates a histogram by using the 
+# Statsample::Graph::Histogram class. This class accepts data 
+# in a Daru::Vector (as created by `rnorm`).
+# 
+# A line showing normal distribution can be drawn by setting 
+# the `:line_normal_distribution` option to *true*.
+# 
+# See this notebook for an illustration: 
+# http://nbviewer.ipython.org/github/SciRuby/sciruby-notebooks/blob/master/statistics/Creating%20a%20Histogram.ipynb
 require 'statsample'
 
 Statsample::Analysis.store(Statsample::Graph::Histogram) do
-  histogram(rnorm(3000,0,20))
+  histogram(rnorm(3000,0,20), :line_normal_distribution => true)
 end
-
 
 if __FILE__==$0
    Statsample::Analysis.run
 end