C++ Boost using newton_raphson_iterate on a class member function - c++

Question

My code below doesn't compile and can't get it why. Is it because I'm using the newton_raphson_iterate in a wrong way?
Do I need to use binding ? Any examples of how using the newton raphson on a member class function is welcome.
class MyB{
struct funct{
double target;
double DerivativePrecision;
int mo;
bool isG;
MyB* bond;
public:
funct(double target_, double DerivativePrecision_, int mo_, bool isG_, MyB* bond_ ) :
target(target_), DerivativePrecision(DerivativePrecision_), mo(mo_), isG(isG_), bond(bond_)
{}
std::tr1::tuple<double,double> operator()(const double& x) const {
double localYtP = bond->yTp(x, mo, isG);
return std::tr1::make_tuple (
localYtP - target,
(bond->yTp(x+DerivativePrecision,mo, isG)-localYtP)/DerivativePrecision
);
}
};
public:
/*
.....
*/
double yTp(double x, int mo, int isG);
double pty(double p, int mo, int isG){
funct localFunc(p, 0.000001, mo, isG, this);
double y = boost::math::tools::newton_raphson_iterate(localFunc(p),
0.1,
-0.1,
0.4,
std::numeric_limits<double>::digits
);
return y;
}
}
int main()
{
system("pause");
return 0;
}
I get two error messages :
First :
\boost/math/tools/roots.hpp(202) : error C2064: term does not evaluate to a function taking 1 arguments
pointing to the last line of this code (BOOST):
template <class F, class T>
T newton_raphson_iterate(F f, T guess, T min, T max, int digits, boost::uintmax_t& max_iter)
{
BOOST_MATH_STD_USING
T f0(0), f1, last_f0(0);
T result = guess;
T factor = static_cast<T>(ldexp(1.0, 1 - digits));
T delta = 1;
T delta1 = tools::max_value<T>();
T delta2 = tools::max_value<T>();
boost::uintmax_t count(max_iter);
do{
last_f0 = f0;
delta2 = delta1;
delta1 = delta;
boost::math::tie(f0, f1) = f(result);
...
The second :
see reference to function template instantiation 'T boost::math::tools::newton_raphson_iterate<std::tr1::tuple<_Arg0,_Arg1>,double>(F,T,T,T,int)' being compiled
pointing (in my class ) to
double y = boost::math::tools::newton_raphson_iterate(localFunc(p),
0.1,
-0.1,
0.4,
std::numeric_limits<double>::digits
);

Answer 1

The problem is you're calling localFunc when trying to invoke newton_raphson_iterate so end up passing a funct as the first template parameter, which is not callable. You should just pass localFunc directly:
newton_raphson_iterate(localFunc, 0.1, -0.1, 0.4, std::numeric_limits<double>::digits);