如何使用 JFreeChart 创建条形图，用可见的提示缩短太长的条形? [英] How can I create a bar-chart with JFreeChart, that shortens too long bars with a visible hint?

问题描述

我想创建一个条形图，但应该缩短非常高的值.一个例子是这张图片:

I want to create a bar-chart, but extraordinary high values should be shortened. An example is this image:

_{(来源:epa.gov)}

我希望很清楚我想要什么.

I hope it is clear what I want.

我的问题是:我如何使用 JFreeChart 做到这一点.如果 JFreeChart 无法实现，您可以推荐替代的开源 Java 库来生成这样的输出.

My question is: How can I do this with JFreeChart. If it isn't possible with JFreeChart you can possibly recommend alternative open-source Java-libraries to produce such an output.

推荐答案

您可以使用 CombinedDomainCategoryPlot 或 CombinedDomainXYPlot 来实现.将第一个图的范围轴设置为您的截止值，然后对第二个图执行类似的操作.然后将它们添加到组合图中.

You could do it with a CombinedDomainCategoryPlot or CombinedDomainXYPlot. Set the range axis of the first plot to your cut off value and then do something similar with the second plot. Then add them to a combined plot.

import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartFrame;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.CombinedDomainCategoryPlot;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.data.category.DefaultCategoryDataset;

public class PlayChart {

    public static void main(String[] args) {


        DefaultCategoryDataset ds = new DefaultCategoryDataset();
        ds.addValue(100, "A", "A");
        ds.addValue(200, "A", "B");
        ds.addValue(400, "A", "C");
        ds.addValue(500, "A", "D");
        ds.addValue(2000, "A", "E");


        JFreeChart bc = ChartFactory.createBarChart("My Bar Chart", "Things", "Counts",  ds, PlotOrientation.VERTICAL, true, false, false);
        JFreeChart bcTop = ChartFactory.createBarChart("My Bar Chart", "Things", "Counts",  ds, PlotOrientation.VERTICAL, true, false, false);

        CombinedDomainCategoryPlot combinedPlot = new CombinedDomainCategoryPlot();
        CategoryPlot topPlot = bcTop.getCategoryPlot();
        NumberAxis topAxis = (NumberAxis) topPlot.getRangeAxis();
        topAxis.setLowerBound(1500);
        topAxis.setUpperBound(2000);

        combinedPlot.add(topPlot, 1);
        CategoryPlot mainPlot = bc.getCategoryPlot();
        combinedPlot.add(mainPlot, 5);

        NumberAxis mainAxis = (NumberAxis) mainPlot.getRangeAxis();;
        mainAxis.setLowerBound(0);
        mainAxis.setUpperBound(600);

        JFreeChart combinedChart = new JFreeChart("Test", combinedPlot);

        ChartFrame cf = new ChartFrame("Test", combinedChart);
        cf.setSize(800, 600);
        cf.setVisible(true);

    }

}

图将共享相同的 X 轴.您需要使用渲染器来设置颜色和标签.

The plots will share the same X-axis. You'll need to play with the renderers to set colours and labels.

删除了无效的 ImageShack 链接

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