euler.cpp

Euler算法

#include<iostream>
#include<math.h>
#define pi 3.141592653
using namespace std;
double f(double t,double y)
{
	return exp(-0.06*pi*t)*((-0.072*pi+2/1.4)*cos(2*t-pi)+(0.3*(0.0036*pi*pi-4)-0.06*pi/1.4+1/1.7)*sin(2*t-pi));
}

double Euler(int j,double h,double w)
{
	double wadd;
	wadd=w+h*f(h*j,w);
	return wadd;
}
int main()
{
	double result=0.00;
	for(int j=1;j<=100;j++)
	{
		cout<<result<<endl;
		result=Euler(j-1,0.1,result);
	}
	return 0;
}