anonymous_namespace{mod_frozen_potential.cpp} Namespace Reference

Classes
class	LinkedList
	class handling linked lists More...

Functions
double	force_ref (const double r, const double a)
double	force_tot (const double r, const double e2)
void	force_short (const Sim_Param &sim, const double D, const LinkedList &linked_list, const std::vector< Particle_v< double >> &particles, const Vec_3D< double > &position, Vec_3D< double > &force, Interp_obj &fs_interp)
void	kick_step_w_pp (const Sim_Param &sim, const double a, const double da, std::vector< Particle_v< double >> &particles, const std::vector< Mesh > &force_field, LinkedList &linked_list, Interp_obj &fs_interp)

Function Documentation

double anonymous_namespace{mod_frozen_potential.cpp}::force_ref	(	const double	r,
		const double	a
	)

Definition at line 46 of file mod_frozen_potential.cpp.

References pow(), and z.

Referenced by force_short(), and App_Var_FP_mod::FP_ppImpl::FP_ppImpl().

                                                   {
    // Reference force for an S_2-shaped particle
    FTYPE_t z = 2 * r / a;
    if (z > 2) return 1 / (r*r);
    else if (z > 1) return (12 / (z*z) - 224 + 896 * z - 840 * z*z + 224 * pow(z, 3) +
                            70 * pow(z, 4) - 48 * pow(z, 5) + 7 * pow(z, 6)) / (35 * a*a);
    else return (224 * z - 224 * pow(z, 3) + 70 * pow(z, 4) + 48 * pow(z, 5) - 21 * pow(z, 7)) / (35 * a*a);
}

void anonymous_namespace{mod_frozen_potential.cpp}::force_short	(	const Sim_Param &	sim,
		const double	D,
		const LinkedList &	linked_list,
		const std::vector< Particle_v< double >> &	particles,
		const Vec_3D< double > &	position,
		Vec_3D< double > &	force,
		Interp_obj &	fs_interp
	)

Definition at line 59 of file mod_frozen_potential.cpp.

References App_Opt::a, Sim_Param::app_opt, Sim_Param::box_opt, force_ref(), force_tot(), get_sgn_distance(), App_Opt::Hc, anonymous_namespace{mod_frozen_potential.cpp}::LinkedList::HOC, IT< points >::iter(), anonymous_namespace{mod_frozen_potential.cpp}::LinkedList::LL, m, Box_Opt::mesh_num, Box_Opt::Ng, p, PI, pow(), pow2(), App_Opt::rs, sqrt(), and IT< points >::vec.

Referenced by kick_step_w_pp().

{   // Calculate short range force in position, force is added
    #define FORCE_SHORT_NO_INTER
    size_t p;
    Vec_3D<FTYPE_t> dr_vec;
    FTYPE_t dr2;
    FTYPE_t dr; // <-- #ifdef FORCE_SHORT_NO_INTER
    const FTYPE_t m = pow((FTYPE_t)sim.box_opt.Ng, 3) / D;
    const size_t Nm = sim.box_opt.mesh_num;
    const FTYPE_t rs2 = pow2(sim.app_opt.rs);
    const FTYPE_t e2 = pow2(sim.box_opt.Ng*0.1); // <-- #ifdef FORCE_SHORT_NO_INTER

    IT<3> it(position, sim.app_opt.Hc);
    do{
        p = linked_list.HOC(it.vec);
        while (p != -1){
            dr_vec = get_sgn_distance(particles[p].position, position, Nm);
            dr2 = dr_vec.norm2();
            if ((dr2 < rs2) && (dr2 != 0)) // Short range force is set 0 for separation larger than cutoff radius
            {
                #ifdef FORCE_SHORT_NO_INTER
                dr = sqrt(dr2);
                force += dr_vec*(force_tot(dr, e2) - force_ref(dr, sim.app_opt.a))*m/(dr*4*PI);
                #else
                force += dr_vec*(m/sqrt(dr2)*fs_interp.eval(dr2));
                #endif
            }
            p = linked_list.LL[p];
        }
    } while( it.iter() );
}

double anonymous_namespace{mod_frozen_potential.cpp}::force_tot	(	const double	r,
		const double	e2
	)

Definition at line 55 of file mod_frozen_potential.cpp.

Referenced by force_short(), and App_Var_FP_mod::FP_ppImpl::FP_ppImpl().

                                                    {
    return 1 / (r*r+e2);
}

void anonymous_namespace{mod_frozen_potential.cpp}::kick_step_w_pp	(	const Sim_Param &	sim,
		const double	a,
		const double	da,
		std::vector< Particle_v< double >> &	particles,
		const std::vector< Mesh > &	force_field,
		LinkedList &	linked_list,
		Interp_obj &	fs_interp
	)

Definition at line 92 of file mod_frozen_potential.cpp.

References assign_from(), Sim_Param::cosmo, force_short(), anonymous_namespace{mod_frozen_potential.cpp}::LinkedList::get_linked_list(), growth_allz::growth_factor, Cosmo_Param::Omega_L(), Cosmo_Param::Omega_m, and pow().

Referenced by App_Var_FP_mod::upd_pos().

{    // 2nd order ODE with long & short range potential
    const size_t Np = particles.size();
    Vec_3D<FTYPE_t> force;
    const FTYPE_t D = growth_factor(a, sim.cosmo);
    const FTYPE_t OL = sim.cosmo.Omega_L()*pow(a,3);
    const FTYPE_t Om = sim.cosmo.Omega_m;
    // -3/2a represents usual EOM, the rest are LCDM corrections
    const FTYPE_t f1 = 3/(2*a)*(Om+2*OL)/(Om+OL);
    const FTYPE_t f2 = 3/(2*a)*Om/(Om+OL)*D/a;
    
    BOOST_LOG_TRIVIAL(debug) << "Creating linked list...";
    linked_list.get_linked_list(particles);

    BOOST_LOG_TRIVIAL(debug) << "Computing short and long range parts of the potential...";
    #pragma omp parallel for private(force)
    for (size_t i = 0; i < Np; i++)
    {
        force.fill(0.);
        assign_from(force_field, particles[i].position, force); // long-range force
        force_short(sim, D, linked_list, particles, particles[i].position, force, fs_interp); // short range force

        force = force*f2 - particles[i].velocity*f1;        
        particles[i].velocity += force*da;
    }
}