ChartDirector 7.0 (Python Edition)

Arbitrary XY Line Chart




This example demonstrates drawing a line chart with arbitrary x coordinates (not increasing or decreasing in one direction), and adding custom data labels to data points.

The x values of the data points are set into the chart using Layer.setXData. ChartDirector merely joins the points together with lines. It does not require the points to following any particular direction.

Note that this example has special labels for the start and end points of the lines. They are created using Layer.addCustomDataLabel.

Source Code Listing

pythondemo\xyline.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 (x, y) data for the first line dataX0 = [20, 90, 40, 30, 12] dataY0 = [10, 40, 75, 54, 20] # The (x, y) data for the second line dataX1 = [10, 40, 75, 54, 60] dataY1 = [50, 90, 40, 30, 10] # Create a XYChart object of size 450 x 450 pixels c = XYChart(450, 450) # Set the plotarea at (55, 65) and of size 350 x 300 pixels, with white background and a light grey # border (0xc0c0c0). Turn on both horizontal and vertical grid lines with light grey color # (0xc0c0c0) c.setPlotArea(55, 65, 350, 300, 0xffffff, -1, 0xc0c0c0, 0xc0c0c0, -1) # Add a legend box at (50, 30) (top of the chart) with horizontal layout. Use 12pt Times Bold Italic # font. Set the background and border color to Transparent. c.addLegend(50, 30, 0, "Times New Roman Bold Italic", 12).setBackground(Transparent) # Add a title to the chart using 18pt Times Bold Itatic font c.addTitle("Reaction Path", "Times New Roman Bold Italic", 18) # Add a title to the y axis using 12pt Arial Bold Italic font c.yAxis().setTitle("Temperature (Celcius)", "Arial Bold Italic", 12) # Set the y axis line width to 3 pixels c.yAxis().setWidth(3) # Add a title to the x axis using 12pt Arial Bold Italic font c.xAxis().setTitle("Pressure (Pa)", "Arial Bold Italic", 12) # Set the x axis line width to 3 pixels c.xAxis().setWidth(3) # Add a red (0xff3333) line layer using dataX0 and dataY0 layer1 = c.addLineLayer(dataY0, 0xff3333, "Compound AAA") layer1.setXData(dataX0) # Set the line width to 3 pixels layer1.setLineWidth(3) # Use 9 pixel square symbols for the data points layer1.getDataSet(0).setDataSymbol(SquareSymbol, 9) # Add custom text labels to the first and last point on the scatter plot using Arial Bold font layer1.addCustomDataLabel(0, 0, "Start", "Arial Bold") layer1.addCustomDataLabel(0, 4, "End", "Arial Bold") # Add a green (0x33ff33) line layer using dataX1 and dataY1 layer2 = c.addLineLayer(dataY1, 0x33ff33, "Compound BBB") layer2.setXData(dataX1) # Set the line width to 3 pixels layer2.setLineWidth(3) # Use 11 pixel diamond symbols for the data points layer2.getDataSet(0).setDataSymbol(DiamondSymbol, 11) # Add custom text labels to the first and last point on the scatter plot using Arial Bold font layer2.addCustomDataLabel(0, 0, "Start", "Arial Bold") layer2.addCustomDataLabel(0, 4, "End", "Arial Bold") # Output the chart c.makeChart("xyline.png")