We Keep Coding

Need basic help formatting date/time for JFreeChart TimeSeries

I need some basic help formatting date/time so that I can add it to my JFreeChart TimeSeries. Because my code is adding duplicates I get the error below the second time through the loop.
I have a temperature sensor we use in healthcare and I need to plot the temp that is read every 30 minutes. So I need my x-axis to be Month-Day-Hour-Minute but I just dont know how to get my time formatted correctly. The line below were I am having issue specifically is " timeSeries.add(new Day(gc.getTime()), temp );"
It's been a really long time since college so I apologize, I think I am close but just can't close the gap. Any help would be appreciated.
thx! L
Output
Sat Nov 20 12:41:00 PST 2021: 72.5 F
TimeSeries.add 20-November-2021
Sat Nov 20 13:11:00 PST 2021: 70.7 F
TimeSeries.add 20-November-2021
Run-time Error when adding duplicates
Exception in thread "main" org.jfree.data.general.SeriesException: You are attempting to add an observation for the time period 20-November-2021 but the series already contains an observation for that time period. Duplicates are not permitted. Try using the addOrUpdate() method.
at org.jfree.data.time.TimeSeries.add(TimeSeries.java:701)
at org.jfree.data.time.TimeSeries.add(TimeSeries.java:746)
at org.jfree.data.time.TimeSeries.add(TimeSeries.java:732)
at dumpMission.main(dumpMission.java:212)
TimeSeries timeSeries = new TimeSeries("Date");
TimeSeriesCollection timeSeriesCollectionTemps = new TimeSeriesCollection();
long time = time_stamp.getTime().getTime() + owc.getFirstLogOffset(state);
GregorianCalendar gc = new GregorianCalendar();
for (int i = 0; i < log.length; i++){
gc.setTime(new Date(time));
System.out.println(gc.getTime() + ": " + Convert.toFahrenheit(owc.decodeTemperature(log [i])) + " F");
time += sample_rate * 60 * 1000;
double temp = Convert.toFahrenheit(owc.decodeTemperature(log [i]));
System.out.println("TimeSeries.add " + new Day(gc.getTime()));
//add needs org.jfree.data.time.RegularTimePeriod
//need to plot month-day-hour-minute
timeSeries.add(new Day(gc.getTime()), temp ); // NEED HELP to get into unique month/day/hour/minute
timeSeriesCollectionTemps.addSeries(timeSeries);
}

As shown here, you can instantiate Minute or any suitable RegularTimePeriod to get the desired effect. As shown here, you can parse your sample date using SimpleDateFormat or ZonedDateTime; the example below uses the former.
import java.awt.Dimension;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.TimeZone;
import javax.swing.JFrame;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.DateAxis;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.renderer.xy.XYLineAndShapeRenderer;
import org.jfree.data.time.Minute;
import org.jfree.data.time.TimeSeries;
import org.jfree.data.time.TimeSeriesCollection;
import org.jfree.data.xy.XYDataset;
/**
* #see https://stackoverflow.com/q/70071299/230513
* #see https://stackoverflow.com/a/12481509/230513
*/
public class TimeTest {
private static XYDataset createDataset() throws ParseException {
SimpleDateFormat f = new SimpleDateFormat("EEE MMM dd HH:mm:ss z yyyy");
TimeSeries series = new TimeSeries("Temperature");
series.add(new Minute(f.parse("Sat Nov 20 12:41:00 PST 2021")), 72.5);
series.add(new Minute(f.parse("Sat Nov 20 13:11:00 PST 2021")), 70.7);
return new TimeSeriesCollection(series);
}
private static JFreeChart createChart(final XYDataset dataset) {
SimpleDateFormat f = new SimpleDateFormat("HH:mm");
f.setTimeZone(TimeZone.getTimeZone("PST"));
JFreeChart chart = ChartFactory.createTimeSeriesChart(
"Test", "Time", "Temperture °F", dataset, true, true, false);
XYPlot plot = (XYPlot) chart.getPlot();
XYLineAndShapeRenderer r = (XYLineAndShapeRenderer) plot.getRenderer();
r.setDefaultShapesVisible(true);
DateAxis domain = (DateAxis) plot.getDomainAxis();
domain.setDateFormatOverride(f);
domain.setVerticalTickLabels(true);
return chart;
}
public static void main(String[] args) throws ParseException {
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
XYDataset dataset = createDataset();
JFreeChart chart = createChart(dataset);
ChartPanel chartPanel = new ChartPanel(chart) {
#Override
public Dimension getPreferredSize() {
return new Dimension(400, 250);
}
};
f.add(chartPanel);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
}

how can I embed 2 bars chart in html using java?

I generate html page with java using gagawa
I now try to add a charts like this:
I have tried org.jfree framework
with this code:
private Img createChart(LatencyHistogram current, LatencyHistogram baseLine) {
Img image = null;
final CategoryDataset dataset = createDataset(current, baseLine);
final JFreeChart chart = ChartFactory.createLineChart(
"Line Chart Demo 1", // chart title
"Type", // domain axis label
"Value", // range axis label
dataset, // data
PlotOrientation.VERTICAL, // orientation
true, // include legend
true, // tooltips
false // urls
);
chart.setBackgroundPaint(java.awt.Color.white);
// save it to an image
try {
final ChartRenderingInfo info = new ChartRenderingInfo(new StandardEntityCollection());
final String pathname = Constants.HTML_PAGES_PATH + "images/latency_delta.png";
final File file1 = new File(pathname);
ChartUtilities.saveChartAsPNG(file1, chart, 600, 400, info);
image = new Img("latency", "../images/latency_delta.png").setWidth("400");
return image;
} catch (IOException e) {
e.printStackTrace();
}
return image;
}
and got this result:
is there any way to create 2 bars chart instead?
is there a more clean and tidy free java charts drawer framework?

to create a bar chart you should use
ChartFactory.createBarChart()
instead of
ChartFactory.createLineChart()
method .but since i don't know what is LatencyHistogram in your code this is not exact code.you have to currently use those data types .
for example following code will generate this
example code
import java.awt.Color;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.renderer.category.BarRenderer;
import org.jfree.data.category.CategoryDataset;
import org.jfree.data.category.DefaultCategoryDataset;
import org.jfree.ui.ApplicationFrame;
import org.jfree.ui.RefineryUtilities;
public class BarChartx extends ApplicationFrame {
public BarChartx(String applicationTitle, String chartTitle) {
super(applicationTitle);
JFreeChart barChart = ChartFactory.createBarChart(chartTitle, "year", "value", createDataset(), PlotOrientation.VERTICAL, true, true, false);
CategoryPlot p = barChart.getCategoryPlot();
BarRenderer renderer = (BarRenderer) p.getRenderer();
renderer.setSeriesPaint(0, new Color(255, 0, 102));
renderer.setSeriesPaint(1, new Color(0, 153, 255));
renderer.setItemMargin(0.03);
ChartPanel chartPanel = new ChartPanel(barChart);
chartPanel.setPreferredSize(new java.awt.Dimension(560, 367));
setContentPane(chartPanel);
}
private CategoryDataset createDataset() {
final String apple = "apple";
final String mango = "mango";
final String y2000 = "2000";
final String y2001 = "2001";
final String y2002 = "2002";
final DefaultCategoryDataset dataset = new DefaultCategoryDataset();
dataset.addValue(700, apple, y2000);
dataset.addValue(550, mango, y2000);
dataset.addValue(700, apple, y2001);
dataset.addValue(550, mango, y2001);
dataset.addValue(720, apple, y2002);
dataset.addValue(570, mango, y2002);
return dataset;
}
public static void main(String[] args) {
BarChartx chart = new BarChartx("example", "Bar Chart Demo 1");
chart.pack();
RefineryUtilities.centerFrameOnScreen(chart);
chart.setVisible(true);
}
}

drawing a diagram with JFreeChart

I'm working with jFreeChart on Eclipse (in Windows) and I want to draw gantt diagram for processors.
I'm doing a XY Chart
But my programme draw me a line with only P0. I want something like
draw from 0 to 10 --> P0
then from 10 to 20 --> draw H
then from 20 to 30 ---->draw wait
from 30 to 40---> draw P0
from 35 to 40 -->draw H
Code:
import javax.swing.JFrame;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.data.xy.XYDataset;
import org.jfree.data.xy.XYSeries;
import org.jfree.data.xy.XYSeriesCollection;
public class JFreeChartLineChartExample extends JFrame {
private static final long serialVersionUID = 1L;
public JFreeChartLineChartExample(String applicationTitle, String chartTitle) {
super(applicationTitle);
// based on the dataset we create the chart
JFreeChart pieChart = ChartFactory.createXYLineChart(chartTitle, "Time", "Processors",
createDataset(),PlotOrientation.VERTICAL, true, true, false);
// Adding chart into a chart panel
ChartPanel chartPanel = new ChartPanel(pieChart);
// settind default size
chartPanel.setPreferredSize(new java.awt.Dimension(500, 270));
// add to contentPane
setContentPane(chartPanel);
}
private XYDataset createDataset() {
final XYSeries P0 = new XYSeries("P0");
P0.add(0, 1);
P0.add(10, 1);
P0.add(35, 1);
P0.add(50, 1);
P0.add(85, 1);
P0.add(110, 1);
final XYSeries P2 = new XYSeries("P2");
final XYSeries P1 = new XYSeries("P1");
final XYSeries H = new XYSeries("H");
H.add(10, 1);
H.add(20, 1);
H.add(45, 1);
H.add(100, 1);
final XYSeries wait = new XYSeries("wait");
wait.add(80, 1);
wait.add(90, 1);
wait.add(105, 1);
final XYSeriesCollection dataset = new XYSeriesCollection();
dataset.addSeries(P0);
dataset.addSeries(P2);
dataset.addSeries(P1);
dataset.addSeries(H);
dataset.addSeries(wait);
return dataset;
}
public static void main(String[] args) {
JFreeChartLineChartExample chart = new JFreeChartLineChartExample(" GANTT ", " GANTT");
chart.pack();
chart.setVisible(true);
}
}

As far as I have understood you want to have gaps in your datasets. Your code paints a straight line from time 0 to 110 for dataset P0 because JFreeChart does not know that you want to have gaps.
To add gaps you need to add null values to your datasets.
For example P0 should be created as follows:
final XYSeries P0 = new XYSeries("P0");
P0.add(0, 1);
P0.add(10, 1);
P0.add(11, null);
P0.add(35, 1);
P0.add(50, 1);
P0.add(51, null);
P0.add(85, 1);
P0.add(110, 1);
You might also have a look at the special Gantt classes provided by JFreeChart. There are some examples in the JFreeChart demo.

draw a multiple plot with JFreechart (bar, XY)

Hello i have to make a program to display power curves, and therefore i need to display three different plots on one window.
The different kind of plots are XY (just points), bar, and XY with lines.
My problem(s) : somehow i can get only two of the charts to get drawn AND i can't change the colors of the single chart correctly.
EDIT : When i put as comment the declaration of the third chart, the second one finally gets drawn. Is it impossible to draw three charts ?
Any help will be greatly appreciated, thanks ;)
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.axis.NumberTickUnit;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.plot.DatasetRenderingOrder;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYBarRenderer;
import org.jfree.chart.renderer.xy.XYItemRenderer;
import org.jfree.chart.renderer.xy.XYLineAndShapeRenderer;
import org.jfree.data.xy.IntervalXYDataset;
import org.jfree.data.xy.XYSeries;
import org.jfree.data.xy.XYSeriesCollection;
import org.jfree.ui.ApplicationFrame;
public class OverlaidPlot extends ApplicationFrame
{
final XYSeries series0 = new XYSeries("Graph0");
final XYSeries series1 = new XYSeries("Graph1");
final XYSeries series2 = new XYSeries("Graph2");
public OverlaidXYPlotDemo(final String title)
{
super(title);
final JFreeChart chart = createOverlaidChart();
final ChartPanel panel = new ChartPanel(chart, true, true, true, true, true);
panel.setPreferredSize(new java.awt.Dimension(800, 600));
setContentPane(panel);
}
public void addElem0(double x, double y)
{
this.series0.add(x, y);
}
public void addElem1(double x, double y)
{
this.series1.add(x, y);
}
public void addElem2(double x, double y)
{
this.series2.add(x, y);
}
private JFreeChart createOverlaidChart()
{
final NumberAxis domainAxis = new NumberAxis("Speed (m/s)");
final ValueAxis rangeAxis = new NumberAxis("Power (kw)");
// create plot ...
final IntervalXYDataset data0 = createDataset0();
final XYItemRenderer renderer0 = new XYBarRenderer(0.20);
// change "new XYBarRenderer(0.20)" to "StandardXYItemRenderer()" if you want to change type of graph
final XYPlot plot = new XYPlot(data0, domainAxis, rangeAxis, renderer0);
// add a second dataset and renderer...
final IntervalXYDataset data1 = createDataset1();
final XYLineAndShapeRenderer renderer1 = new XYLineAndShapeRenderer(false, true);
// arguments of new XYLineAndShapeRenderer are to activate or deactivate the display of points or line. Set first argument to true if you want to draw lines between the points for e.g.
plot.setDataset(1, data1);
plot.setRenderer(1, renderer1);
// add a third dataset and renderer...
final IntervalXYDataset data2 = createDataset2();
final XYLineAndShapeRenderer renderer2 = new XYLineAndShapeRenderer(true, true);
// arguments of new XYLineAndShapeRenderer are to activate or deactivate the display of points or line. Set first argument to true if you want to draw lines between the points for e.g.
plot.setDataset(1, data2);
plot.setRenderer(1, renderer2);
plot.setDatasetRenderingOrder(DatasetRenderingOrder.FORWARD);
NumberAxis domain = (NumberAxis) plot.getDomainAxis();/*
domain.setRange(0.00, 30);*/
domain.setTickUnit(new NumberTickUnit(0.5));
domain.setVerticalTickLabels(true);
// return a new chart containing the overlaid plot...
return new JFreeChart("Test", JFreeChart.DEFAULT_TITLE_FONT, plot, true);
}
private IntervalXYDataset createDataset0()
{
// create dataset 0...
final XYSeriesCollection coll0 = new XYSeriesCollection(series0);
return coll0;
}
private IntervalXYDataset createDataset1()
{
// create dataset 1...
final XYSeriesCollection coll1 = new XYSeriesCollection(series1);
return coll1;
}
private IntervalXYDataset createDataset2()
{
// create dataset 2...
final XYSeriesCollection coll2 = new XYSeriesCollection(series2);
return coll2;
}
}

You have two datasets at the same index within the plot - make sure you're setting each dataset to a unique index:
plot.setDataset(2, data2);
plot.setRenderer(2, renderer2);
After changing this, I ran your example with some test data and was able to see all three data sets plotted.

Multiple axes on the same data

I'm trying to have two axes on the same data.
The data is a couple of DefaultTableXYDatasets. The plot is a XYPlot, and I have two XYLineAndShapeRenderers and one StackedXYAreaRenderer2.
All data is in meters for the y-values, and I want to have one axis displaying it in meters and one axis displaying it in feet. Now this feels like a common thing to do, but I can't decide on the most obvious way to do it. One way that works would be to duplicate the data and have the y-values in feet, then add another NumberAxis and be done with it.
But I thought it would be wiser to subclass NumberAxis, or inject some functionality into NumberAxis to scale the values. Or should I go with the first approach?
What do you think?

To avoid duplicating data, you can use the XYPlot method mapDatasetToRangeAxes() to map a dataset index to a list of axis indices. In the example below, meters is the principle axis, and the range of the corresponding feet axis is scaled accordingly, as shown here. Note that invokeLater() is required to ensure that the feet axis is scaled after any change in the meters axis.
import java.awt.EventQueue;
import java.util.Arrays;
import java.util.List;
import javax.swing.JFrame;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.AxisLocation;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.event.AxisChangeEvent;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYItemRenderer;
import org.jfree.chart.renderer.xy.XYLineAndShapeRenderer;
import org.jfree.data.xy.XYDataset;
import org.jfree.data.xy.XYSeries;
import org.jfree.data.xy.XYSeriesCollection;
/**
* #see https://stackoverflow.com/q/13358758/230513
*/
public class AxisTest {
private static final int N = 5;
private static final double FEET_PER_METER = 3.28084;
private static XYDataset createDataset() {
XYSeriesCollection data = new XYSeriesCollection();
final XYSeries series = new XYSeries("Data");
for (int i = -N; i < N * N; i++) {
series.add(i, i);
}
data.addSeries(series);
return data;
}
private JFreeChart createChart(XYDataset dataset) {
NumberAxis meters = new NumberAxis("Meters");
NumberAxis feet = new NumberAxis("Feet");
ValueAxis domain = new NumberAxis();
XYItemRenderer renderer = new XYLineAndShapeRenderer();
XYPlot plot = new XYPlot(dataset, domain, meters, renderer);
plot.setRangeAxis(1, feet);
plot.setRangeAxisLocation(1, AxisLocation.BOTTOM_OR_LEFT);
List<Integer> axes = Arrays.asList(0, 1);
plot.mapDatasetToRangeAxes(0, axes);
scaleRange(feet, meters);
meters.addChangeListener((AxisChangeEvent event) -> {
EventQueue.invokeLater(() -> {
scaleRange(feet, meters);
});
});
JFreeChart chart = new JFreeChart("Axis Test",
JFreeChart.DEFAULT_TITLE_FONT, plot, true);
return chart;
}
private void scaleRange(NumberAxis feet, NumberAxis meters) {
feet.setRange(meters.getLowerBound() * FEET_PER_METER,
meters.getUpperBound() * FEET_PER_METER);
}
private void display() {
JFrame f = new JFrame("AxisTest");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(new ChartPanel(createChart(createDataset())));
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(() -> {
new AxisTest().display();
});
}
}
Alternatively, you can use a JCheckBox to flip between the two series, meters & feet, as shown in this related example. Using the methods available to XYLineAndShapeRenderer, you can hide a second series' lines, shapes and legend. The series itself must be visible to establish the axis range.

Eventually i settled on this solution, it might not be the most elegant but it worked. I have a second axis feetAxis, and added a AxisChangeListener on the first axis called meterAxis. When the meterAxis changes set the range on feetAxis.
I used SwingUtilities.invokeLater, otherwise the range would be incorrect when zooming out of the chart, then the feetAxis would only go from 0 to 1. Didn't check why though.
feetAxis = new NumberAxis("Height [ft]");
metersAxis = new NumberAxis("Height [m]");
pathPlot.setRangeAxis(0, metersAxis);
pathPlot.setRangeAxis(1, feetAxis);
metersAxis.addChangeListener(new AxisChangeListener() {
#Override
public void axisChanged(AxisChangeEvent event) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
feetAxis.setRange(metersAxis.getLowerBound() * MetersToFeet, metersAxis.getUpperBound() * MetersToFeet);
}
});
}
});