Seer is a lightweight, semantically rich wrapper for the Google Visualization API. It allows you to easily create a visualization of data in a variety of formats, including area charts, bar charts, column charts, gauges, line charts, and pie charts.

Add the following to the head of the page that will display a chart, or add it to your layout file:

<%= Seer::init_visualization -%>

Gather the data you want to visualize in an instance variable in your controller, then use the visualize method to insert the appropriate chart in your view.

In your controller:

# @data must be an array, and each object in the array must respond to the data method specified
# in the visualize call (in this example, 'quantity')
@data = Widget.all

In your view:

<div id="chart"></div>

<%= Seer::visualize(
      @widgets, 
      :as => :bar_chart,
      :in_element => 'chart',
      :series => {:series_label => 'name', :data_method => 'quantity'},
      :chart_options => {
        :height => 300,
        :width => 200 * @widgets.size,
        :is_3_d => false,
        :legend => 'none',
        :colors => ["#990000"],
        :title => "Widget Quantities",
        :title_x => 'Quantity',
        :title_y => 'Widgets'
      }
    )
 -%>

For examples of additional chart types, refer to the documentation for each of the individual chart objects, or see the blog post announcing Seer: Simple, Semantic Graphing for Ruby on Rails with Seer

A sample project that demonstrates each of the chart types is available on GitHub.

Seer is developed and maintained by Corey Ehmke at SEO Logic.

Copyright © 2010 Corey Ehmke / SEO Logic, released under the MIT license