ChartDirector Ver 5.0 (Python Edition)

Polar Vector Chart




This example demonstrates a polar vector chart.

A vector chart is like a scatter chart, but the symbols are arrows which can be of arbitrary lengths pointing to arbitrary directions. Thus each symbol in a vector chart is specified by 4 values - the radial and angular coordinates, and the length and the direction.

In ChartDirector, a polar vector layer is created using PolarChart.addVectorLayer.

Source Code Listing

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

# Coordinates of the starting points of the vectors
radius = [5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
    10, 10, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 20, 20, 20, 20, 20, 20,
    20, 20, 20, 20, 20, 20, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25]
angle = [0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120,
    150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270,
    300, 330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90,
    120, 150, 180, 210, 240, 270, 300, 330]

# Magnitude and direction of the vectors
magnitude = [5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
    3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1,
    1, 1, 1, 1, 1, 1, 1, 1, 1]
direction = [60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120, 150,
    180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300,
    330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120,
    150, 180, 210, 240, 270, 300, 330, 0, 30]

# Create a PolarChart object of size 460 x 460 pixels
c = PolarChart(460, 460)

# Add a title to the chart at the top left corner using 15pts Arial Bold Italic font
c.addTitle("Polar Vector Chart Demonstration", "arialbi.ttf", 15)

# Set center of plot area at (230, 240) with radius 180 pixels
c.setPlotArea(230, 240, 180)

# Set the grid style to circular grid
c.setGridStyle(0)

# Set angular axis as 0 - 360, with a spoke every 30 units
c.angularAxis().setLinearScale(0, 360, 30)

# Add a polar vector layer to the chart with blue (0000ff) vectors
c.addVectorLayer(radius, angle, magnitude, direction, RadialAxisScale, '0x0000ff')

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

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

# Coordinates of the starting points of the vectors
radius = [5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
    10, 10, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 20, 20, 20, 20, 20, 20,
    20, 20, 20, 20, 20, 20, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25]
angle = [0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120,
    150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270,
    300, 330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90,
    120, 150, 180, 210, 240, 270, 300, 330]

# Magnitude and direction of the vectors
magnitude = [5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
    3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1,
    1, 1, 1, 1, 1, 1, 1, 1, 1]
direction = [60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120, 150,
    180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300,
    330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120,
    150, 180, 210, 240, 270, 300, 330, 0, 30]

# Create a PolarChart object of size 460 x 460 pixels
c = PolarChart(460, 460)

# Add a title to the chart at the top left corner using 15pts Arial Bold Italic font
c.addTitle("Polar Vector Chart Demonstration", "arialbi.ttf", 15)

# Set center of plot area at (230, 240) with radius 180 pixels
c.setPlotArea(230, 240, 180)

# Set the grid style to circular grid
c.setGridStyle(0)

# Set angular axis as 0 - 360, with a spoke every 30 units
c.angularAxis().setLinearScale(0, 360, 30)

# Add a polar vector layer to the chart with blue (0000ff) vectors
c.addVectorLayer(radius, angle, magnitude, direction, RadialAxisScale, '0x0000ff')

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