void main ()
{
void rk3(real_t *, real_t, real_t, real_t *, real_t, real_t *, real_t,
real_t (*)(real_t, real_t), real_t [], real_t [], int);
int n,i,fi;
real_t x,y,z,e[6],d[6],x3,s,term,
b[4]={0.25, 0.50, 0.75, 1.00};
e[1]=e[3]=1.0e-6;
e[2]=e[4]=1.0e-6;
printf("RK3 delivers :\n");
for (i=0; i<=3; i++) {
fi=(b[i] < 0.3);
rk3(&x,0.0,b[i],&y,0.0,&z,1.0,fxy,e,d,fi);
x3=x*x*x;
term=x;
s=0.0;
n=3;
do {
s += term;
term=term*x3/n/(n+1);
n += 3;
} while (fabs(term) > 1.0e-14);
printf("Y-YEXACT= %+e X= %4.2f Y= %8.6f\n",y-s,x,y);
}
}
int main(int narg, char* argc[])
{
std::vector<Function*> functions;
functions.push_back( new Function1() );
functions.push_back( new Function2() );
functions.push_back( new Function3() );
RungeKutta rk3(argc[1], functions, 2);
rk3.solveProblem();
return 0;
}