odeint c++ do_step openmp - c++

Question

I'm trying to use solve my ode system and use openmp. When I try stepper.do_step with:
typedef runge_kutta_dopri5< state_type , double , state_type , double , openmp_range_algebra > stepper;
I define my state_type as std::vector
And I compile I get:
error: expected unqualified-id before '.' token stepper.do_step(c , Y , t, dt );
Is it a problem of my typedef or I can't use do_step with openmp?
#include <boost/numeric/odeint.hpp>
#include<omp.h>
#include <boost/numeric/odeint/external/openmp/openmp.hpp>
typedef std::vector< double > state_type;
struct T
{
double m_param1;
double m_param2;
};
class sys
{
struct T T1;
public:
sys(struct T G) : T1(G) {}
void operator() ( state_type const& Y , state_type& dY , double t )
{
const size_t N = Y.size();
#pragma omp parallel for schedule(runtime)
for (size_t aux = 0; aux <= N; aux++) {
mdlfnt(Y,dY,t,T1.m_currents,T1.m_stim); //Here is my ode system
}
}
};
struct T T2;
state_type Y(45); // initial conditions
void main()
{
typedef runge_kutta_dopri5< state_type , double , state_type , double , openmp_range_algebra , default_operations , never_resizer > stepper;
int number_threads = 1;
omp_set_num_threads(number_threads);
int chunk_size = omp_get_max_threads();
omp_set_schedule( omp_sched_static , chunk_size );
for(int i=0;i<nd;i++){
sys c(T2);
stepperdo_step(c , Y , t, dt );
}
}