ChartDirector 5.1 (Python Edition)

Percentage Bar Chart




This example demonstrates creating a percentage bar chart with a legend box. It also demonstrates gradient background color, rounded frame, soft drop shadow, and using CDML to include custom icons in the legend box.

A percentage bar chart is like a stacked bar chart, except the bars are individually scaled so that they stacked up to 100.

The key features demonstrated in this example are:

Note that by default, the data label format is {percent}% (showing the percentage) for a percentage bar layer, as opposed to {value} (showing the data value) for other types of bar layer. The data label format can be modified using Layer.setDataLabelFormat.

Source Code Listing

[Standalone Version] pythondemo\percentbar.py
#!/usr/bin/python
from pychartdir import *

# The data for the bar chart
data0 = [100, 125, 245, 147, 67]
data1 = [85, 156, 179, 211, 123]
data2 = [97, 87, 56, 267, 157]

# The labels for the bar chart
labels = ["Mon", "Tue", "Wed", "Thu", "Fri"]

# Create a XYChart object of size 500 x 320 pixels. Use a vertical gradient color
# from pale blue (e8f0f8) to sky blue (aaccff) spanning half the chart height as
# background. Set border to blue (88aaee). Use rounded corners. Enable soft drop
# shadow.
c = XYChart(500, 320)
c.setBackground(c.linearGradientColor(0, 0, 0, c.getHeight() / 2, 0xe8f0f8, 0xaaccff
    ), 0x88aaee)
c.setRoundedFrame()
c.setDropShadow()

# Add a title to the chart using 15 points Arial Italic. Set top/bottom margins to 15
# pixels.
title = c.addTitle("Weekly Product Sales", "ariali.ttf", 15)
title.setMargin2(0, 0, 15, 15)

# Tentatively set the plotarea to 50 pixels from the left edge, and to just under the
# title. Set the width to 60% of the chart width, and the height to 50 pixels from
# the bottom edge. Use pale blue (e8f0f8) background, transparent border, and grey
# (aaaaaa) grid lines.
c.setPlotArea(50, title.getHeight(), c.getWidth() * 6 / 10, c.getHeight(
    ) - title.getHeight() - 50, 0xe8f0f8, -1, Transparent, 0xaaaaaa)

# Add a legend box where the top-right corner is anchored at 10 pixels from the right
# edge, and just under the title. Use vertical layout and 8 points Arial font.
legendBox = c.addLegend(c.getWidth() - 10, title.getHeight(), 1, "arial.ttf", 8)
legendBox.setAlignment(TopRight)

# Set the legend box background and border to transparent
legendBox.setBackground(Transparent, Transparent)

# Set the legend box icon size to 16 x 32 pixels to match with custom icon size
legendBox.setKeySize(16, 32)

# Set axes to transparent
c.xAxis().setColors(Transparent)
c.yAxis().setColors(Transparent)

# Set the labels on the x axis
c.xAxis().setLabels(labels)

# Add a percentage bar layer
layer = c.addBarLayer2(Percentage)

# Add the three data sets to the bar layer, using icons images with labels as data
# set names
layer.addDataSet(data0, 0x66aaee,
    "<*block,valign=absmiddle*><*img=service.png*> Service<*/*>")
layer.addDataSet(data1, 0xeebb22,
    "<*block,valign=absmiddle*><*img=software.png*> Software<*/*>")
layer.addDataSet(data2, 0xcc88ff,
    "<*block,valign=absmiddle*><*img=computer.png*> Hardware<*/*>")

# Use soft lighting effect with light direction from top
layer.setBorderColor(Transparent, softLighting(Top))

# Enable data label at the middle of the the bar
layer.setDataLabelStyle().setAlignment(Center)

# For a vertical stacked chart with positive data only, the last data set is always
# on top. However, in a vertical legend box, the last data set is at the bottom. This
# can be reversed by using the setLegend method.
layer.setLegend(ReverseLegend)

# Adjust the plot area size, such that the bounding box (inclusive of axes) is 15
# pixels from the left edge, just below the title, 10 pixels to the right of the
# legend box, and 15 pixels from the bottom edge.
c.packPlotArea(15, title.getHeight(), c.layoutLegend().getLeftX() - 10, c.getHeight(
    ) - 15)

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

[CGI Version] pythondemo_cgi\percentbar.py
#!/usr/bin/python
from pychartdir import *

# The data for the bar chart
data0 = [100, 125, 245, 147, 67]
data1 = [85, 156, 179, 211, 123]
data2 = [97, 87, 56, 267, 157]

# The labels for the bar chart
labels = ["Mon", "Tue", "Wed", "Thu", "Fri"]

# Create a XYChart object of size 500 x 320 pixels. Use a vertical gradient color
# from pale blue (e8f0f8) to sky blue (aaccff) spanning half the chart height as
# background. Set border to blue (88aaee). Use rounded corners. Enable soft drop
# shadow.
c = XYChart(500, 320)
c.setBackground(c.linearGradientColor(0, 0, 0, c.getHeight() / 2, 0xe8f0f8, 0xaaccff
    ), 0x88aaee)
c.setRoundedFrame()
c.setDropShadow()

# Set directory for loading images to current script directory
# Need when running under Microsoft IIS
c.setSearchPath(os.path.dirname(sys.argv[0]))

# Add a title to the chart using 15 points Arial Italic. Set top/bottom margins to 15
# pixels.
title = c.addTitle("Weekly Product Sales", "ariali.ttf", 15)
title.setMargin2(0, 0, 15, 15)

# Tentatively set the plotarea to 50 pixels from the left edge, and to just under the
# title. Set the width to 60% of the chart width, and the height to 50 pixels from
# the bottom edge. Use pale blue (e8f0f8) background, transparent border, and grey
# (aaaaaa) grid lines.
c.setPlotArea(50, title.getHeight(), c.getWidth() * 6 / 10, c.getHeight(
    ) - title.getHeight() - 50, 0xe8f0f8, -1, Transparent, 0xaaaaaa)

# Add a legend box where the top-right corner is anchored at 10 pixels from the right
# edge, and just under the title. Use vertical layout and 8 points Arial font.
legendBox = c.addLegend(c.getWidth() - 10, title.getHeight(), 1, "arial.ttf", 8)
legendBox.setAlignment(TopRight)

# Set the legend box background and border to transparent
legendBox.setBackground(Transparent, Transparent)

# Set the legend box icon size to 16 x 32 pixels to match with custom icon size
legendBox.setKeySize(16, 32)

# Set axes to transparent
c.xAxis().setColors(Transparent)
c.yAxis().setColors(Transparent)

# Set the labels on the x axis
c.xAxis().setLabels(labels)

# Add a percentage bar layer
layer = c.addBarLayer2(Percentage)

# Add the three data sets to the bar layer, using icons images with labels as data
# set names
layer.addDataSet(data0, 0x66aaee,
    "<*block,valign=absmiddle*><*img=service.png*> Service<*/*>")
layer.addDataSet(data1, 0xeebb22,
    "<*block,valign=absmiddle*><*img=software.png*> Software<*/*>")
layer.addDataSet(data2, 0xcc88ff,
    "<*block,valign=absmiddle*><*img=computer.png*> Hardware<*/*>")

# Use soft lighting effect with light direction from top
layer.setBorderColor(Transparent, softLighting(Top))

# Enable data label at the middle of the the bar
layer.setDataLabelStyle().setAlignment(Center)

# For a vertical stacked chart with positive data only, the last data set is always
# on top. However, in a vertical legend box, the last data set is at the bottom. This
# can be reversed by using the setLegend method.
layer.setLegend(ReverseLegend)

# Adjust the plot area size, such that the bounding box (inclusive of axes) is 15
# pixels from the left edge, just below the title, 10 pixels to the right of the
# legend box, and 15 pixels from the bottom edge.
c.packPlotArea(15, title.getHeight(), c.layoutLegend().getLeftX() - 10, c.getHeight(
    ) - 15)

# Output the chart
print("Content-type: image/png\n")
binaryPrint(c.makeChart2(PNG))