This is an Jupyter notebook backed by a Ruby kernel

I am developing IRuby a kernel in Ruby that adheres to the Jupyter/IPython messaging protocol. It integrates nicely with different Rubygems as will be shown later.

What does this give you?

This gives us a very fancy web notebook interface for Ruby. It's a very good tool for programming presentations. It's basically an in-browser REPL loop, with some extra goodies.

Usage

Install IRuby with:

gem install iruby

Start the IRuby notebook with:

iruby notebook

Example

$stdout and $stderr are redirected to the notebook

puts 'Hello, world!'

Hello, world!

$stderr.puts 'Error!'

Error!

The last computed result is returned.

Math.sqrt(2)

1.4142135623730951

This works even for images.

File.open('IRuby Examples/ruby.svg')

File.open('IRuby Examples/ruby.png')

Display

IRuby provides a method to display objects IRuby.display and methods to create $\LaTeX$ and HTML representations.

IRuby.display '<b style="color:green">Hello, world!</b>', mime: 'text/html'

Hello, world!

IRuby.html '<iframe src=http://en.mobile.wikipedia.org/?useformat=mobile width=700 height=350></iframe>'

$\LaTeX$ is rendered using MathJax.

IRuby.display IRuby.latex <<-'TEX'
\begin{eqnarray}
\nabla \times \vec{\mathbf{B}} -\, \frac1c\, \frac{\partial\vec{\mathbf{E}}}{\partial t} & = \frac{4\pi}{c}\vec{\mathbf{j}} \\
\nabla \cdot \vec{\mathbf{E}} & = 4 \pi \rho \\
\nabla \times \vec{\mathbf{E}}\, +\, \frac1c\, \frac{\partial\vec{\mathbf{B}}}{\partial t} & = \vec{\mathbf{0}} \\
\nabla \cdot \vec{\mathbf{B}} & = 0 
\end{eqnarray}
TEX

IRuby.math('F(k) = \int_{-\infty}^{\infty} f(x) e^{2\pi i k} dx')

\begin{eqnarray} \nabla \times \vec{\mathbf{B}} -\, \frac1c\, \frac{\partial\vec{\mathbf{E}}}{\partial t} & = \frac{4\pi}{c}\vec{\mathbf{j}} \\ \nabla \cdot \vec{\mathbf{E}} & = 4 \pi \rho \\ \nabla \times \vec{\mathbf{E}}\, +\, \frac1c\, \frac{\partial\vec{\mathbf{B}}}{\partial t} & = \vec{\mathbf{0}} \\ \nabla \cdot \vec{\mathbf{B}} & = 0 \end{eqnarray}

$$F(k) = \int_{-\infty}^{\infty} f(x) e^{2\pi i k} dx$$

Arrays and Hashes can be printed as HTML tables.

IRuby.display IRuby.table([1,2,[],3])
IRuby.display IRuby.table({a:1,b:2,c:3})
IRuby.display IRuby.table([[11,12,13,14],[21,22,23],'not an Array',[31,32,33,34]])
IRuby.display IRuby.table({a:[11,12,13,14],b:[21,22,23],c:[31,32,33,34]})
IRuby.display IRuby.table([{a:1,b:2,c:3},'not an Array',{a:2,b:3,c:4,e:5}])
IRuby.display IRuby.table([{a:1,b:2,c:3},{a:2,b:3,c:4,d:5},{0=>:x,1=>:y},[:a,:b,:c]])

1

2

3

a	b	c
1	2	3

11	12	13	14
21	22	23
not an Array
31	32	33	34

a	b	c
11	21	31
12	22	32
13	23	33
14		34

a	b	c	e
1	2	3
not an Array
2	3	4	5

a	b	c	d	0	1	2
1	2	3
2	3	4	5
				x	y
				a	b	c

Integration with Ruby gems

Pry

Pry is an enhanced Ruby REPL. It will be automatically used by IRuby if available. You can use the code browsing utilities for example.

ls Array

Object.methods: yaml_tag
Array.methods: []  try_convert
Array#methods: 
  &            concat      hash                reject                slice     
  *            count       include?            reject!               slice!    
  +            cycle       index               repeated_combination  sort      
  -            delete      insert              repeated_permutation  sort!     
  <<           delete_at   inspect             replace               sort_by!  
  <=>          delete_if   join                reverse               take      
  ==           drop        keep_if             reverse!              take_while
  []           drop_while  last                reverse_each          to_a      
  []=          each        length              rindex                to_ary    
  any?         each_index  map                 rotate                to_h      
  assoc        empty?      map!                rotate!               to_s      
  at           eql?        pack                sample                transpose 
  bsearch      fetch       permutation         select                uniq      
  clear        fill        pop                 select!               uniq!     
  collect      find_index  pretty_print        shelljoin             unshift   
  collect!     first       pretty_print_cycle  shift                 values_at 
  combination  flatten     product             shuffle               zip       
  compact      flatten!    push                shuffle!              |         
  compact!     frozen?     rassoc              size                

Gnuplot

Gnuplot::Plot objects are automatically displayed inline as SVG.

require 'gnuplot'

Gnuplot::Plot.new do |plot|  
    plot.xrange '[-0.5:0.5]'
    plot.title  'Example plot'
    plot.ylabel 'x'
    plot.xlabel 'sin(1/x)'
    plot.samples 10000
    plot.data << Gnuplot::DataSet.new('sin(1/x)') do |ds|
        ds.with = 'lines'
        ds.linewidth = 2
    end
end

You can also create nice 3D plots

Gnuplot::SPlot.new do |plot|
    plot.title 'Spiral'
    plot.nokey
    plot.parametric
    plot.hidden3d
    plot.view '80,50'
    plot.isosamples '60,15'
    plot.xrange '[-8:8]'
    plot.yrange '[-8:8]'
    plot.zrange '[-8:8]'
    plot.urange '[-2*pi:2*pi]'
    plot.vrange '[-pi:pi]'
    plot.data << Gnuplot::DataSet.new('cos(u)*(cos(v)+3), sin(u)*(cos(v)+3), sin(v)+u') do |ds|
        ds.with = 'lines'
    end
end

Rubyvis

Rubyvis objects are automatically displayed inline as SVG.

require 'rubyvis'
    
Rubyvis::Panel.new do 
  width 150
  height 150
  bar do
    data [1, 1.2, 1.7, 1.5, 0.7, 0.3]
    width 20
    height {|d| d * 80}
    bottom(0)
    left {index * 25}
  end
end

Matrix & GSL

Matrix and GSL::Matrix objects are automatically displayed as $\LaTeX$.

require 'matrix'
Matrix[[1,2,3],[1,2,3]]

$$\left(\begin{array}{ccc} 1&2&3\\ 1&2&3\\ \end{array}\right)$$

Nyaplot

require 'nyaplot'

x = []; y = []; theta = 0.6; a=1
while theta < 14*Math::PI do
  x.push(a*Math::cos(theta)/theta)
  y.push(a*Math::sin(theta)/theta)
  theta += 0.1
end
plot1 = Nyaplot::Plot.new
plot1.add(:line, x, y)
plot1.show