Example 2: Difference

This example uses the same data as Example 1. The first number of lost observations are excluded from W due to differencing, and the number of lost observations is also output.

import com.imsl.stat.*;

public class  DifferenceEx2 {
    public static void main(String args[]) {
        
        int periods[] = {1, 12};
        int nLost;
        double[] z={
            112.0,118.0,132.0,129.0,121.0,135.0,
            148.0,148.0,136.0,119.0,104.0,118.0,
            115.0,126.0,141.0,135.0,125.0,149.0,
            170.0,170.0,158.00,133.0,114.0,140.0
        };
        
        Difference diff = new Difference();
        diff.excludeFirst(true);
        double[] out = diff.compute(z, periods);
        nLost = diff.getObservationsLost();
        
        System.out.println("The number of observation lost = "
        + nLost);
        for (int i=0; i < out.length; i++)
            System.out.println(out[i]);
    }
}

Output

The number of observation lost = 13
5.0
1.0
-3.0
-2.0
10.0
8.0
0.0
0.0
-8.0
-4.0
12.0