bibun - 経済統計練習帳

package math;
 
 
import org.apache.commons.math3.ode.*;
import org.apache.commons.math3.analysis.*;
import org.apache.commons.math3.ode.FirstOrderIntegrator.*;
import org.apache.commons.math3.ode.nonstiff.HighamHall54Integrator;
 
class pro{
 
public static void main(String[] args) {
 
pro test=new pro();
}
 
pro(){
double minstep =0.1;
        double maxstep=1.0;
 
        double abt=0.001;
        double rt=0.001;
 
 
        FirstOrderDifferentialEquations fode = new FirstOrderDifferentialEquations() {
 
            public int getDimension() {
                return 1;
            }
 
            public void computeDerivatives(double x, double[] y, double[] dy){
                dy[0]=0.01*x+y[0];
            }
        };
 
        HighamHall54Integrator h54 = new HighamHall54Integrator(minstep,maxstep,abt,rt);
 
 
        double [] yp={2};
        double x;
        double []y={7};
        double y2;
 
        for(x=1;x<10.0;x++){
 
                h54.integrate(fode, 0, yp, x, y);
                y2 = y[0];
         System.out.println(x);     
        System.out.println(y2);   
        }
 
}
}