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Creating Boxplots with daru and statsample¶

Description¶

This example illustrates how daru, combined with Statsample::Graph::Boxplot can be used for generating box plots of a normally distributed set of data.

The 'rnorm' function, defined in statsample/shorthands generates a Daru::Vector object which contains the specified number of random variables in a normal distribution. It uses the 'distribution' gem for this purpose.

In [1]:

require 'daru' require 'statsample' include Statsample::Shorthand

n = 30 a = rnorm(n-1,50,10) b = rnorm(n, 30,5) c = rnorm(n,5,1)

Append 2 to vector 'a' at the end

a.push(2, a.size)

a.class

Create a boxplot of the data by specifying the vectors a, b and c and providing necessary options to Statsample::Graph::Boxplot.¶

The `#to_svg` function returns the boxplot image in a raw SVG format. To display this properly in iruby we need to pass that output to the `IRuby.svg` method.¶

In [3]:

IRuby.svg boxplot(:vectors=>[a,b,c],:width=>300, :height=>300, :groups=>%w{first first second}, :minimum=>0).to_svg

Out[3]:

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