how to plot a line graph using jfreechart reading from text file?

[priti]

hello
In the below code we are able to read y-axis but not able to read x-axis on the graph.. can tel me how to read x-axis on the graph.
thanks in advance

import java.io.*;
import java.util.*;//Scanner is included
import org.jfree.chart.*;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.data.category.DefaultCategoryDataset;
import org.jfree.data.general.DefaultPieDataset;
import org.jfree.data.xy.*;
import org.jfree.data.*;
public class Plot_1
{
static Scanner scanner;
static XYSeries series;
//static File file;
public static void main(String[] args)
{
plotResult();



}//end of main





//**********



//Method that reads in an external file with numbers (doubles)

//and plots the content in a line chart using JFreeChart





public static void plotResult() {



//Read in the file "calculation.txt" using Scanner and call hasNextDouble on it



try {

int index = 0;



File file = new File("data.txt");

series = new XYSeries("Pk");

scanner = new Scanner(file);

// Scanner scanner = new Scanner(file);

while (scanner.hasNextDouble()) {

series.add(index++,scanner.nextDouble());

}

scanner.close();

}

catch (FileNotFoundException e) {
e.printStackTrace();

}





//Round off the doubles to two decimals - not done yet







//Plot the line chart







/*

XYSeries series = new XYSeries("Pk");

series.add(1, 0.8201791789916324 );

series.add(2, 0.9727097916233601 );

series.add(3, 0.9949972829175494);

*/



XYDataset xyDataset = new XYSeriesCollection(series);





JFreeChart chart = ChartFactory.createXYLineChart

("Temp = 85", "k", "Pk",xyDataset, PlotOrientation.VERTICAL, true, true, false);

ChartFrame frame1=new ChartFrame("XYLine Chart",chart);

frame1.setVisible(true);

frame1.setSize(600,400);







}//End of method





//***************





}//end of class

in data.txt has following values
x y
1 20
2 30
4 50

[Norm]

Cross posted at how to plot the line graph using jfreechart reading from text file