public static double newtonDecent(func func, dfunc dfunc)
{
double x0 = 0;
double x1 = x0 + 1;
double step = 0.0002;
int i = 0;
bool first = true;
while (Math.Abs(func.Invoke(x1) - func.Invoke(x0)) > 0.00000001)
{
if (!first)
{
x0 = x1;
first = false;
}
x1 = x0 + step * dfunc.Invoke(x1);
if (func.Invoke(x1) < func.Invoke(x0))
{
step /= 2;
}
else
{
step *= 2;
}
i++;
}
return(func.Invoke(x1));
}
// 再帰関数
static decimal newton(decimal x, func f, dfunc df)
{
return(x - f(x) / df(x));
}
