ChartDirector 6.0 (Ruby Edition)

Circular Zones




This example demonstrates adding circular zones to a polar chart.

In ChartDirector, a zone defined on the radial axis will mark a radius range, and so will appear as ring on a polar chart.

This example contains three circular zones in the plot area background, colored as red, green and blue. The blue region is the original background of the plot area, while the red and green regions are added using Axis.addZone of the radial axis object.

Source Code Listing

[Ruby On Rails Version - Controller] app/controllers/polarzones_controller.rb
require("chartdirector")

class PolarzonesController < ApplicationController

    def index()
        @title = "Circular Zones"
        @ctrl_file = File.expand_path(__FILE__)
        @noOfCharts = 1
        render :template => "templates/chartview"
    end

    #
    # Render and deliver the chart
    #
    def getchart()
        # The data for the chart
        data = [51, 15, 51, 40, 17, 87, 94, 21, 35, 88, 50, 60]

        # The labels for the chart
        labels = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sept", "Oct", "Nov",
            "Dec"]

        # Create a PolarChart object of size 400 x 420 pixels
        c = ChartDirector::PolarChart.new(400, 420)

        # Set background color to a 2 pixel pattern color, with a black border and 1 pixel 3D border
        # effect
        c.setBackground(c.patternColor([0xffffff, 0xe0e0e0], 2), 0, 1)

        # Add a title to the chart using 16pt Arial Bold Italic font. The title text is white
        # (0xffffff) on 2 pixel pattern background
        c.addTitle("Chemical Concentration", "arialbi.ttf", 16, 0xffffff).setBackground(
            c.patternColor([0x000000, 0x000080], 2))

        # Set center of plot area at (200, 240) with radius 145 pixels. Set background color to blue
        # (9999ff)
        c.setPlotArea(200, 240, 145, 0x9999ff)

        # Color the region between radius = 40 to 80 as green (99ff99)
        c.radialAxis().addZone(40, 80, 0x99ff99)

        # Color the region with radius > 80 as red (ff9999)
        c.radialAxis().addZone(80, 999, 0xff9999)

        # Set the grid style to circular grid
        c.setGridStyle(false)

        # Set the radial axis label format
        c.radialAxis().setLabelFormat("{value} ppm")

        # Use semi-transparent (40ffffff) label background so as not to block the data
        c.radialAxis().setLabelStyle().setBackground(0x40ffffff, 0x40000000)

        # Add a legend box at (200, 30) top center aligned, using 9pt Arial Bold font. with a black
        # border.
        legendBox = c.addLegend(200, 30, false, "arialbd.ttf", 9)
        legendBox.setAlignment(ChartDirector::TopCenter)

        # Add legend keys to represent the red/green/blue zones
        legendBox.addKey("Under-Absorp", 0x9999ff)
        legendBox.addKey("Normal", 0x99ff99)
        legendBox.addKey("Over-Absorp", 0xff9999)

        # Add a blue (000080) spline line layer with line width set to 3 pixels and using yellow
        # (ffff00) circles to represent the data points
        layer = c.addSplineLineLayer(data, 0x000080)
        layer.setLineWidth(3)
        layer.setDataSymbol(ChartDirector::CircleShape, 11, 0xffff00)

        # Set the labels to the angular axis as spokes.
        c.angularAxis().setLabels(labels)

        # Output the chart
        send_data(c.makeChart2(ChartDirector::PNG), :type => "image/png", :disposition => "inline")

    end

end

[Ruby On Rails Version - View] app/views/templates/chartview.html.erb
<html>
<body style="margin:5px 0px 0px 5px">

<!-- Title -->
<div style="font-size:18pt; font-family:verdana; font-weight:bold">
    <%= @title %>
</div>
<hr style="border:solid 1px #000080" />

<!-- Source Code Listing Link -->
<div style="font-size:9pt; font-family:verdana; margin-bottom:1.5em">
    <%= link_to "Source Code Listing", 
        :controller => "cddemo", :action => "viewsource",
        :ctrl_file => @ctrl_file, :view_file => File.expand_path(__FILE__) %>
</div>

<!-- Create one or more IMG tags to display the demo chart(s) -->
<% 0.upto(@noOfCharts - 1) do |i| %>
    <img src="<%= url_for(:action => "getchart", :img => i) %>">
<% end %>

</body>
</html>

[Command Line Version] rubydemo/polarzones.rb
#!/usr/bin/env ruby
require("chartdirector")

# The data for the chart
data = [51, 15, 51, 40, 17, 87, 94, 21, 35, 88, 50, 60]

# The labels for the chart
labels = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sept", "Oct", "Nov", "Dec"]

# Create a PolarChart object of size 400 x 420 pixels
c = ChartDirector::PolarChart.new(400, 420)

# Set background color to a 2 pixel pattern color, with a black border and 1 pixel 3D border effect
c.setBackground(c.patternColor([0xffffff, 0xe0e0e0], 2), 0, 1)

# Add a title to the chart using 16pt Arial Bold Italic font. The title text is white (0xffffff) on
# 2 pixel pattern background
c.addTitle("Chemical Concentration", "arialbi.ttf", 16, 0xffffff).setBackground(c.patternColor([
    0x000000, 0x000080], 2))

# Set center of plot area at (200, 240) with radius 145 pixels. Set background color to blue
# (9999ff)
c.setPlotArea(200, 240, 145, 0x9999ff)

# Color the region between radius = 40 to 80 as green (99ff99)
c.radialAxis().addZone(40, 80, 0x99ff99)

# Color the region with radius > 80 as red (ff9999)
c.radialAxis().addZone(80, 999, 0xff9999)

# Set the grid style to circular grid
c.setGridStyle(false)

# Set the radial axis label format
c.radialAxis().setLabelFormat("{value} ppm")

# Use semi-transparent (40ffffff) label background so as not to block the data
c.radialAxis().setLabelStyle().setBackground(0x40ffffff, 0x40000000)

# Add a legend box at (200, 30) top center aligned, using 9pt Arial Bold font. with a black border.
legendBox = c.addLegend(200, 30, false, "arialbd.ttf", 9)
legendBox.setAlignment(ChartDirector::TopCenter)

# Add legend keys to represent the red/green/blue zones
legendBox.addKey("Under-Absorp", 0x9999ff)
legendBox.addKey("Normal", 0x99ff99)
legendBox.addKey("Over-Absorp", 0xff9999)

# Add a blue (000080) spline line layer with line width set to 3 pixels and using yellow (ffff00)
# circles to represent the data points
layer = c.addSplineLineLayer(data, 0x000080)
layer.setLineWidth(3)
layer.setDataSymbol(ChartDirector::CircleShape, 11, 0xffff00)

# Set the labels to the angular axis as spokes.
c.angularAxis().setLabels(labels)

# Output the chart
c.makeChart("polarzones.png")