Polygon Bar Shapes

This example demonstrates bars of various polygonal shapes.

ChartDirector supports bars in cylindrical or arbitrary polygonal shapes. This is specified by using BarLayer.setBarShape and BarLayer.setBarShape2. In this example, various polygonal shapes are illustrated.

See Shape Specification on how built-in and custom shapes are defined in ChartDirector.

For demonstration, in this example each bar is of a different shape. BarLayer.setBarShape and BarLayer.setBarShape2 also supports setting the bar shapes based on data groups (or data sets) or data item position. For an example, see Multi-Shape Bar Chart.

pythondemo\polygonbar.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 bar chart
data = [85, 156, 179.5, 211, 123, 176, 195]

# The labels for the bar chart
labels = ["Square", "Star(8)", "Polygon(6)", "Cross", "Cross2", "Diamond", "Custom"]

# Create a XYChart object of size 500 x 280 pixels.
c = XYChart(500, 280)

# Set the plotarea at (50, 40) with alternating light grey (f8f8f8) / white (ffffff) background
c.setPlotArea(50, 40, 400, 200, 0xf8f8f8, 0xffffff)

# Add a title to the chart using 14pt Arial Bold Italic font
c.addTitle("    Bar Shape Demonstration", "Arial Bold Italic", 14)

# Add a multi-color bar chart layer
layer = c.addBarLayer3(data)

# Set layer to 3D with 10 pixels 3D depth
layer.set3D(10)

# Set bar shape to circular (cylinder)
layer.setBarShape(CircleShape)

# Set the first bar (index = 0) to square shape
layer.setBarShape(SquareShape, 0, 0)

# Set the second bar to 8-pointed star
layer.setBarShape(StarShape(8), 0, 1)

# Set the third bar to 6-sided polygon
layer.setBarShape(PolygonShape(6), 0, 2)

# Set the next 3 bars to cross shape, X shape and diamond shape
layer.setBarShape(CrossShape(), 0, 3)
layer.setBarShape(Cross2Shape(), 0, 4)
layer.setBarShape(DiamondShape, 0, 5)

# Set the last bar to a custom shape, specified as an array of (x, y) points in normalized
# coordinates
customShape = [-500, 0, 0, 500, 500, 0, 500, 1000, 0, 500, -500, 1000]
layer.setBarShape2(customShape, 0, 6)

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

# Add a title to the y axis
c.yAxis().setTitle("Frequency")

# Add a title to the x axis
c.xAxis().setTitle("Shapes")

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