Question

我有一个折线图，它可以创建平滑的曲线而不是锯齿状的图。（我通过渲染器（以XYSplineRenderer为例）进行此操作）

该曲线应在数据点处具有拐点，但在该点之上或之下上升，并且看起来不佳且具有误导性（暗示某些数据存在于最大值和/或最小值之下）

产生此代码的代码：

import java.awt.Color;
import java.awt.Font;
import java.awt.Point;
import java.awt.geom.Ellipse2D;
import java.io.File;
import java.io.FileOutputStream;
import java.text.SimpleDateFormat;

import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartUtils;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.DateAxis;
import org.jfree.chart.axis.DateTickUnit;
import org.jfree.chart.axis.DateTickUnitType;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.axis.TickUnits;
import org.jfree.chart.labels.XYItemLabelGenerator;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYSplineRenderer;
import org.jfree.data.time.Day;
import org.jfree.data.time.TimeSeries;
import org.jfree.data.time.TimeSeriesCollection;
import org.jfree.data.xy.XYDataset;

public class LineChart {

    public String saveToFile(String path,String pathColor) {
        try {

            JFreeChart chart = getChart(pathColor,"","","",false);
            Point p = new Point(400,300);
            File chartFile = new File(path);
            ChartUtils.writeChartAsPNG(new FileOutputStream(chartFile), chart, Double.valueOf(p.getX()).intValue(), Double.valueOf(p.getY()).intValue(),false,0);

        } catch (Throwable t) {
            t.printStackTrace();
        }
        return null;
    }

    private JFreeChart getChart(
            String hexColor,
            String title,
            String category,
            String value,
            boolean includeLegend) {

        TimeSeriesCollection dataset = new TimeSeriesCollection();
        TimeSeries series1 = new TimeSeries("Total");
        series1.add(new Day(7,10,2019),0);
        series1.add(new Day(8,10,2019),6);
        series1.add(new Day(9,10,2019),0);
        series1.add(new Day(10,10,2019),2);
        series1.add(new Day(11,10,2019),0);

        dataset.addSeries(series1);

        XYSplineRenderer renderer = new XYSplineRenderer();
        renderer.setDrawOutlines(true);
        renderer.setPrecision(1000);

        renderer.setDrawSeriesLineAsPath(true);

        renderer.setSeriesPaint(0, Color.decode(hexColor)); 
        renderer.setSeriesShapesVisible(0,  true);
        renderer.setSeriesItemLabelsVisible(0, true);
        renderer.setSeriesItemLabelPaint(0, Color.decode(hexColor));
        renderer.setSeriesShape(0, new Ellipse2D.Double(-3, -3, 6, 6));

        renderer.setSeriesItemLabelGenerator(0, new XYItemLabelGenerator() {

            @Override
            public String generateLabel(XYDataset dataset, int series, int item) {
                Double d = dataset.getYValue(series, item);
                return "" + d.intValue();
            }
        });

        JFreeChart chart = ChartFactory.createTimeSeriesChart(title, category, value, null,includeLegend, true, false);
        chart.setAntiAlias(true);
        XYPlot plot = (XYPlot)chart.getPlot();
        plot.setRangeGridlinePaint(new Color(155, 155, 155) );
        plot.setBackgroundPaint(new Color(0, 0, 0, 0));

        final TickUnits standardUnits = new TickUnits();
        standardUnits.add(
                new DateTickUnit(DateTickUnitType.DAY, 1, new SimpleDateFormat("dd E"))
        );

        DateAxis domainAxis = (DateAxis)plot.getDomainAxis();
        domainAxis.setTickLabelFont(new Font("Montserrat",Font.BOLD, 10));
        domainAxis.setTickLabelPaint(Color.decode("#9b9b9b"));

        domainAxis.setStandardTickUnits(standardUnits);

        final NumberAxis rangeAxis = (NumberAxis) plot.getRangeAxis();
        rangeAxis.setStandardTickUnits(NumberAxis.createIntegerTickUnits());
        rangeAxis.setTickLabelFont(new Font("Montserrat",Font.BOLD, 10));
        rangeAxis.setTickLabelPaint(Color.decode("#9b9b9b"));

        plot.setDataset(0, dataset);
        plot.setRenderer(0, renderer);
        plot.setOutlinePaint(null);
        return chart;
    }
}

jfreechart折线图曲线无法打开拐点

0 个答案: