https://github.com/mrpowers/prawn_charts

Prawn gem to develop vector line charts
https://github.com/mrpowers/prawn_charts

Last synced: 3 months ago
JSON representation

Prawn gem to develop vector line charts

• Host: GitHub
• URL: https://github.com/mrpowers/prawn_charts
• Owner: MrPowers
• License: mit
• Created: 2013-07-22T23:30:49.000Z (over 11 years ago)
• Default Branch: master
• Last Pushed: 2013-10-26T18:40:10.000Z (about 11 years ago)
• Last Synced: 2023-04-01T11:26:17.309Z (over 1 year ago)
• Language: Ruby
• Size: 465 KB
• Stars: 5
• Watchers: 4
• Forks: 2
• Open Issues: 3
• Metadata Files:
  • Readme: README.md
  • License: LICENSE.txt

Awesome Lists containing this project

README

        
[![Code Climate](https://codeclimate.com/github/MrPowers/prawn_charts.png)](https://codeclimate.com/github/MrPowers/prawn_charts)

# Prawn Charts

Prawn Charts is a Prawn graphing library to create linear or log line

charts in Prawn with no dependencies other than Prawn.

## Examples

Clone the respository and run the following script to generate a PDF

file with a log graph on your Desktop:

```bash

$ ruby lib/prawn_charts/examples/log_example.rb

```

This script will generate a PDF file of a log graph that is only 6KB.

![alt tag](https://raw.github.com/MrPowers/prawn_charts/master/images/prawn_charts_log_example.png)

Prawn Charts can also be used to generate linear graphs.  This graph

does not leverage some built in features (i.e. graph title, y label, x label)

and demonstrates that Prawn Charts is easily customizable.

![alt tag](https://raw.github.com/MrPowers/prawn_charts/master/images/simple_linear_example.png)

## Contributing

Please send pull requests - they will be merged :)

## Code Organization

The DataCollectors (located in lib/data_collectors) are responsible for

converting input data to pdf_points, so it can be graphed.  

The RenderingAssistant is responsible for parsing the input hash and

combining user specified data with smart defaults.  The graph is fully

customizable, but smart defaults allow for rapid prototyping.

The PrawnChartRenderer module should be mixed in to Prawn::Document, so the

draw_graph method can be called directly on the Prawn::Document object.

See the lib/prawn_charts/examples/ directory for examples on how to use

this gem.

## Example Input

The entire log example is included in this README for easy reference:

```ruby

Prawn::Document.extensions << PrawnCharts::PrawnChartRenderer

pdf = Prawn::Document.new

data = [

  {x_label: "Apr-11", y: 1_000},

  {x_label: "May-11", y: nil},

  {x_label: "Jun-11", y: nil},

  {x_label: "Jul-11", y: nil},

  {x_label: "Aug-11", y: 300_000},

  {x_label: "Sep-11", y: nil},

  {x_label: "Oct-11", y: nil},

  {x_label: "Dec-11", y: 17},

  {x_label: "Jan-12", y: nil},

  {x_label: "Feb-12", y: nil},

  {x_label: "Mar-12", y: 10},

  {x_label: "Apr-12", y: nil},

  {x_label: "May-12", y: nil},

  {x_label: "Jun-12", y: 1_000_000}

]

orange = "D95D2E"

green = "62C545"

white = "FFFFFF"

colors = {

  :rectangle_fill => white,

  :line => green,

  :dots => orange

}

input = {

  :graph => {

    :starting_point => [100, 400],

    :width => 300,

    :height => 200,

    :data => data,

    :y_labels => ["1", "10", "100", "1,000", "10,000", "100,000", "1,000,000"],

    :scale => :log

  },

  :dots => {},

  :y_labels => {

    :offset => -62,

    :text_box_options => {:width => 55, :align => :right}

  },

  :x_labels => {},

  :horizontal_lines => true,

  :graph_title => { :title => "cool graph" },

  :x_title => { :title => "x title" },

  :y_title => { :title => "y title", :offset => -60 },

}

pdf.draw_graph(input, colors)

pdf.render_file(Dir.home + "/desktop/log_prawn_graph.pdf")

```

The following code illustrates most of the inputs that can be set to

configure the graph:

```ruby

data = [{y: 5, x_label: "Jan 11"}, {y: 17, x_label: "Feb 11"}, {y: 14, x_label: "Mar 11"}]

input = {

  :graph => {:starting_point => [100, 200], :width => 300, :height => 200, :data => data, :y_labels => [0, 5, 10, 15, 20]},

  :dots => { :radius => 4 },

  :horizontal_lines => true,

  :graph_title => { :title => "cool graph", :offset => 50, :text_box_options => {} },

  :x_title => { :title => "x title", :offset => -60, :text_box_options => {} },

  :y_title => { :title => "y title", :offset => -50, :text_box_options => {} },

  :x_labels => { :offset => -50, :text_box_options => { :width => 100, :height => 20, align: :center, rotate: 45 } },

  :y_labels => { :offset => -40, :text_box_options => { :height => 40, valign: :center } }

}

```