Primary and Second Axis

Possible Usage Scenarios

When the numbers in a chart vary widely from data series to data series, or when you have mixed types of data (price and volume), plot one or more data series on a secondary vertical (value) axis. The scale of the secondary vertical axis shows the values for the associated data series. A secondary axis works well in a chart that shows a combination of column and line charts.

Handle Primary and Second Axis like Microsoft Excel

Please see the following sample code that create a new Excel file and put values of the chart in the first worksheet. Then we add a chart and show the second-axis.

The following sample code generates the output Excel file.

Sample Code

		// Create an instance of Workbook
		Workbook workbook = new Workbook();
		// Access the first worksheet.
		Worksheet worksheet = workbook.getWorksheets().get(0);
		// Put the sample values used in a chart
		worksheet.getCells().get("A1").putValue("Region");
		worksheet.getCells().get("A2").putValue("Peking");
		worksheet.getCells().get("A3").putValue("New York");
		worksheet.getCells().get("A4").putValue("Paris");
		worksheet.getCells().get("B1").putValue("Sales Volume");
		worksheet.getCells().get("C1").putValue("Growth Rate");
		worksheet.getCells().get("B2").putValue(100);
		worksheet.getCells().get("B3").putValue(80);
		worksheet.getCells().get("B4").putValue(140);
		worksheet.getCells().get("C2").putValue(0.7);
		worksheet.getCells().get("C3").putValue(0.8);
		worksheet.getCells().get("C4").putValue(1.0);
		// Create a Scatter chart 
		int pieIdx = worksheet.getCharts().add(ChartType.SCATTER, 6, 6, 15, 11);
		// Retrieve the Chart object
		Chart chart = worksheet.getCharts().get(pieIdx);
		// Add Series
		chart.getNSeries().add("B2:C4", true);
		// Set the category data
		chart.getNSeries().setCategoryData("=Sheet1!$A$2:$A$4"); 
		// Set the Second-Axis 
		chart.getNSeries().get(1).setPlotOnSecondAxis(true); 
		// Show the Second-Axis
		chart.getSecondValueAxis().setVisible(true);
		// Set the second series ChartType to line
		chart.getNSeries().get(1).setType(ChartType.LINE); 
		// Set the series name 
		chart.getNSeries().get(0).setName("Sales Volume");
		chart.getNSeries().get(1).setName("Growth Rate");
		// Set the Legend at the bottom of the chart area
		chart.getLegend().setPosition(LegendPositionType.BOTTOM);
		// Fill the PlotArea area with nothing 
		chart.getPlotArea().getArea().getFillFormat().setFillType(FillType.NONE); 
		// Save the file
		workbook.save("PrimaryandSecondaryAxis.xlsx");