Example: The cubic spline interpolant

A cubic spline interpolant to a function is computed. The value of the spline at point 0.25 is printed.
import com.imsl.math.*;

public class CsInterpolateEx1 {
    public static void main(String args[]) {
        int		n = 11;
        double	x[] = new double[n];
        double	y[] = new double[n];
        
        for (int k = 0;  k < n;  k++) {
            x[k] = (double)k/(double)(n-1);
            y[k] = Math.sin(15.0*x[k]);
        }
        
        CsInterpolate cs = new CsInterpolate(x, y);
        double csv =  cs.value(0.25);
        System.out.println("The computed cubic spline value at point .25 is "
        + csv);
    }
}

Output

The computed cubic spline value at point .25 is -0.5487725038121579
Link to Java source.