Stacked Area Chart

This example demonstrates using multiple data sets to create stacked area chart.

The key features demonstrated in this example are:

Add a stacked area layer using XYChart.addAreaLayer2 with the Stack predefined constant.
Add multiple data sets to the area layer using Layer.addDataSet.
Add a legend at the bottom of the chart using BaseChart.addLegend/
Set the y-axis label format to "US$nn" using Axis.setLabelFormat.

pythondemo\stackedarea.py

#!/usr/bin/python

# The ChartDirector for Python module is assumed to be in "../lib"
import sys, os
sys.path.insert(0, os.path.join(os.path.abspath(sys.path[0]), "..", "lib"))

from pychartdir import *

# The data for the area chart
data0 = [42, 49, 33, 38, 51, 46, 29, 41, 44, 57, 59, 52, 37, 34, 51, 56, 56, 60, 70, 76, 63, 67, 75,
    64, 51]
data1 = [50, 45, 47, 34, 42, 49, 63, 62, 73, 59, 56, 50, 64, 60, 67, 67, 58, 59, 73, 77, 84, 82, 80,
    84, 89]
data2 = [61, 79, 85, 66, 53, 39, 24, 21, 37, 56, 37, 22, 21, 33, 13, 17, 4, 23, 16, 25, 9, 10, 5, 7,
    16]
labels = ["0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "10", "11", "12", "13", "14", "15",
    "16", "17", "18", "19", "20", "21", "22", "23", "24"]

# Create a XYChart object of size 300 x 210 pixels. Set the background to pale yellow (0xffffc0)
# with a black border (0x0)
c = XYChart(300, 210, 0xffffc0, 0x000000)

# Set the plotarea at (50, 30) and of size 240 x 140 pixels. Use white (0xffffff) background.
c.setPlotArea(50, 30, 240, 140).setBackground(0xffffff)

# Add a legend box at (50, 185) (below of plot area) using horizontal layout. Use 8pt Arial font
# with Transparent background.
c.addLegend(50, 185, 0, "", 8).setBackground(Transparent)

# Add a title box to the chart using 8pt Arial Bold font, with yellow (0xffff40) background and a
# black border (0x0)
c.addTitle("Sales Volume", "Arial Bold", 8).setBackground(0xffff40, 0)

# Set the y axis label format to US$nnnn
c.yAxis().setLabelFormat("US${value}")

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

# Display 1 out of 2 labels on the x-axis. Show minor ticks for remaining labels.
c.xAxis().setLabelStep(2, 1)

# Add an stack area layer with three data sets
layer = c.addAreaLayer2(Stack)
layer.addDataSet(data0, 0x4040ff, "Store #1")
layer.addDataSet(data1, 0xff4040, "Store #2")
layer.addDataSet(data2, 0x40ff40, "Store #3")

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