The Logarithmic Line Chart works as expected and gives a chart with straight line.
However, simply substituting XYChart for CategoryChart gives a chart with the bars completely off; it seems as they are actually still linearly scaled, whereas the y axis labels are correct:
Linear scale:
Log scale:
Apparently this issue exists in all version down to at least version 3.1.0.
/**
* Logarithmic Y-Axis
*
* Demonstrates the following:
* <ul>
* <li>Logarithmic Y-Axis
* <li>Building a Chart with ChartBuilder
* <li>Place legend at Inside-NW position
*/
public class CategoryChart01 {
public static void main(String[] args) {
CategoryChart01 exampleChart = new CategoryChart01();
CategoryChart chart = exampleChart.getChart();
new SwingWrapper<CategoryChart>(chart).displayChart();
}
public CategoryChart getChart() {
// generates Log data
List<Integer> xData = new ArrayList<Integer>();
List<Double> yData = new ArrayList<Double>();
for (int i = -3; i <= 3; i++) {
xData.add(i);
yData.add(Math.pow(10, i));
}
// Create Chart
// XYChart chart = new XYChartBuilder().width(800).height(600).title("Powers of Ten").xAxisTitle("Power").yAxisTitle("Value").build();
CategoryChart chart = new CategoryChartBuilder().width(800).height(600).title("Powers of Ten").xAxisTitle("Power").yAxisTitle("Value").build();
// Customize Chart
chart.getStyler().setChartTitleVisible(true);
chart.getStyler().setLegendPosition(LegendPosition.InsideNW);
chart.getStyler().setYAxisLogarithmic(true);
chart.getStyler().setYAxisMin(0.001);
chart.getStyler().setYAxisMax(1000.0);
// Series
chart.addSeries("10^x", xData, yData);
return chart;
}
}
The Logarithmic Line Chart works as expected and gives a chart with straight line.
However, simply substituting XYChart for CategoryChart gives a chart with the bars completely off; it seems as they are actually still linearly scaled, whereas the y axis labels are correct:
Linear scale:
Log scale:
Apparently this issue exists in all version down to at least version 3.1.0.