ChartDirector Ver 5.0 (Python Edition)

Vector Chart




This example demonstrates a 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 x and y coordinates, the length and the direction.

In ChartDirector, an XY vector layer is created using XYChart.addVectorLayer.

Source Code Listing

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

# The (x, y) coordinates of the starting point of the vectors
dataX = [20, 40, 60, 80, 100, 20, 40, 60, 80, 100, 20, 40, 58, 62, 80, 100, 20, 40,
    60, 80, 100, 20, 40, 60, 80, 100]
dataY = [20, 20, 20, 20, 20, 40, 40, 40, 40, 40, 60, 60, 60, 60, 60, 60, 80, 80, 80,
    80, 80, 100, 100, 100, 100, 100]

# The lengths (radii) and directions (angles) of the vectors
dataR = [6, 6, 9, 6, 6, 6, 9, 12, 9, 6, 9, 12, 12, 12, 12, 9, 6, 9, 12, 9, 6, 6, 6,
    9, 6, 6]
dataA = [-45, -30, 0, 30, 45, -60, -45, 0, 45, 60, -90, -90, -90, 90, 90, 90, -120,
    -135, 180, 135, 120, -135, -150, 180, 150, 135]

# Create a XYChart object of size 450 x 390 pixels
c = XYChart(450, 390)

# Set the plotarea at (55, 40) and of size 350 x 300 pixels, with a light grey border
# (0xc0c0c0). Turn on both horizontal and vertical grid lines with light grey color
# (0xc0c0c0)
c.setPlotArea(55, 40, 350, 300, -1, -1, '0xc0c0c0', '0xc0c0c0', -1)

# Add a title to the chart using 18 pts Times Bold Itatic font.
c.addTitle("Vector Chart Demonstration", "timesbi.ttf", 18)

# Add a title to the y axis using 12 pts Arial Bold Italic font
c.yAxis().setTitle("Y Axis Title", "arialbi.ttf", 12)

# Add a title to the x axis using 12 pts Arial Bold Italic font
c.xAxis().setTitle("X Axis Title", "arialbi.ttf", 12)

# Set the axes line width to 3 pixels
c.xAxis().setWidth(3)
c.yAxis().setWidth(3)

# Add a vector layer to the chart using blue (0000CC) color, with vector arrow size
# set to 11 pixels
c.addVectorLayer(dataX, dataY, dataR, dataA, YAxisScale, '0x0000cc').setArrowHead(11)

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

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

# The (x, y) coordinates of the starting point of the vectors
dataX = [20, 40, 60, 80, 100, 20, 40, 60, 80, 100, 20, 40, 58, 62, 80, 100, 20, 40,
    60, 80, 100, 20, 40, 60, 80, 100]
dataY = [20, 20, 20, 20, 20, 40, 40, 40, 40, 40, 60, 60, 60, 60, 60, 60, 80, 80, 80,
    80, 80, 100, 100, 100, 100, 100]

# The lengths (radii) and directions (angles) of the vectors
dataR = [6, 6, 9, 6, 6, 6, 9, 12, 9, 6, 9, 12, 12, 12, 12, 9, 6, 9, 12, 9, 6, 6, 6,
    9, 6, 6]
dataA = [-45, -30, 0, 30, 45, -60, -45, 0, 45, 60, -90, -90, -90, 90, 90, 90, -120,
    -135, 180, 135, 120, -135, -150, 180, 150, 135]

# Create a XYChart object of size 450 x 390 pixels
c = XYChart(450, 390)

# Set the plotarea at (55, 40) and of size 350 x 300 pixels, with a light grey border
# (0xc0c0c0). Turn on both horizontal and vertical grid lines with light grey color
# (0xc0c0c0)
c.setPlotArea(55, 40, 350, 300, -1, -1, '0xc0c0c0', '0xc0c0c0', -1)

# Add a title to the chart using 18 pts Times Bold Itatic font.
c.addTitle("Vector Chart Demonstration", "timesbi.ttf", 18)

# Add a title to the y axis using 12 pts Arial Bold Italic font
c.yAxis().setTitle("Y Axis Title", "arialbi.ttf", 12)

# Add a title to the x axis using 12 pts Arial Bold Italic font
c.xAxis().setTitle("X Axis Title", "arialbi.ttf", 12)

# Set the axes line width to 3 pixels
c.xAxis().setWidth(3)
c.yAxis().setWidth(3)

# Add a vector layer to the chart using blue (0000CC) color, with vector arrow size
# set to 11 pixels
c.addVectorLayer(dataX, dataY, dataR, dataA, YAxisScale, '0x0000cc').setArrowHead(11)

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