Численные методы. Лекции, задания, примеры / Metod_Renge-Kutta_kod_Variant_4

#include <iostream>
#include  <stdio.h>
#include  <math.h>
#include  <stdlib.h>
#include <conio.h>

using namespace std;



double ytoch(double x)
{
	double y;
	y=sin(x);
	return y;
}
double f(double x, double y)
{
	double z;
	z=cos(x);
	return z;
}
int main ()
{
	int n,i;
	double a,b,y0,x,y2,dy,h,z,y;
	cout<<"vvedi a  b  n y0, \n";
	cin>>a>>b>>n>>y0;
	h=(b-a)/n;
	x=a;
	y=y0;
	for (i=1; i<=n; i++)
	{
	y2=ytoch(x);x=x+h;
	y=y+h*f(x+h/2,y+h/2*f(x,y));
	
	

	dy=(fabs((y-y2)/y))*100;
	
	cout<<"\n   x="<<x<<"   y ="<<y<<"   y2="<<y2<< "       dy  = "<<dy<<"%\n";
	}
	getch ();
	return 0;
}