Getting multiple datasets from JFreeChart

Question

I am using JFreeChart to have 2 datasets on the same graph. I am trying to do a comparison between how similar the points are on the graph and therefore I need access to the 2 datasets I put into the chart previously, but for some reason I can't seem to extract this information.

Here is how the data is input:

 private static IntervalXYDataset createDataset()
 {
     DefaultXYDataset completeDataset = new DefaultXYDataset();

     //populate with simulated data
     double[][] sim = new double[2][simData.size()];
     for(int i = 0; i < simData.size(); i++){
         sim[0][i] = simData.get(i).getOne();
         sim[1][i] = simData.get(i).getTwo();
     }

     //populated with known experimental data         
     double[][] exp = new double[2][expData.size()];
     for(int i = 0; i < expData.size(); i++){
         exp[0][i] = expData.get(i).getOne();
         exp[1][i] = expData.get(i).getTwo();
     }

     completeDataset.addSeries("Simulated", sim);
     completeDataset.addSeries("Experimental", exp);

     XYBarDataset dataset = new XYBarDataset(completeDataset, .1);

     return dataset; 
 }

The data is stored as a Pair initially, but this I know the data is input as the graph shows it correctly. How can I return the two series in this dataset?

Answer 1

If I understand correctly, you want to retrieve your 2 datasets from completeDataset?

As DefaultXYDataset has some limitations, you could try something like this as a workaround. I haven't tested it so it might need some tweaking :)

    completeDataset .addSeries("Simulated", sim); //"Simulated" will be at position 0
    completeDataset .addSeries("Experimental", exp); //"Experimental" will be at position 1

    //get series length
    int countSeries1 = completeDataset.getItemCount(0); //number of items in Simulated
    int countSeries2 = completeDataset.getItemCount(1); //number of items in Experimental

    double[][] series1 = new double[2][countSeries1];
    double[][] series2 = new double[2][countSeries2];

    //recreate Simulated series
    for(int i = 0; i < countSeries1; i++){

        series1[0][i] = completeDataset.getXValue(0, i);
        series1[1][i] = completeDataset.getYValue(0, i);

    }
    //recreate Experimental series
    for(int i = 0; i < countSeries2; i++){

        series2[0][i] = completeDataset.getXValue(1, i);
        series2[1][i] = completeDataset.getYValue(1, i);

    }