inline static
typename std::enable_if<ExpansionTraits<Kernel>::has_M2M>::type
eval(const Kernel& K,
const typename Kernel::multipole_type& source,
typename Kernel::multipole_type& target,
const typename Kernel::point_type& translation) {
K.M2M(source, target, translation);
}
void two_level_test(const Kernel& K)
{
typedef Kernel kernel_type;
typedef typename kernel_type::point_type point_type;
typedef typename kernel_type::source_type source_type;
typedef typename kernel_type::target_type target_type;
typedef typename kernel_type::charge_type charge_type;
typedef typename kernel_type::result_type result_type;
typedef typename kernel_type::multipole_type multipole_type;
typedef typename kernel_type::local_type local_type;
// init source
std::vector<source_type> s(1);
s[0] = source_type(0,0,0);
// init charge
std::vector<charge_type> c(1);
c[0][0] = 1.;
c[0][1] = 2.;
c[0][2] = 3.;
c[0][3] = 1.;
c[0][4] = 0.;
c[0][5] = 1.;
// init target
std::vector<target_type> t(1);
t[0] = target_type(0.98,0.98,0.98);
// init results vectors for exact, FMM
std::vector<result_type> rexact(1);
result_type rm2p;
result_type rfmm;
// test direct
K.P2P(s.begin(),s.end(),c.begin(),t.begin(),t.end(),rexact.begin());
// setup intial multipole expansion
multipole_type M;
const point_type M_center(0.05, 0.05, 0.05);
INITM::eval(K, M, M_center, 2u);
K.P2M(s[0], c[0], M_center, M);
// perform M2M
multipole_type M2;
const point_type M2_center(0.1, 0.1, 0.1);
INITM::eval(K, M2, M2_center, 1u);
K.M2M(M, M2, M2_center - M_center);
//K.P2M(s,c,M2_center,M2);
// test M2P
K.M2P(M2, M2_center, t[0], rm2p);
// test M2L, L2P
#ifndef TREECODE_ONLY
local_type L2;
point_type L2_center(0.9, 0.9, 0.9);
INITL::eval(K, L2, L2_center, 1u);
K.M2L(M2, L2, L2_center - M2_center);
// test L2L
local_type L;
point_type L_center(0.95, 0.95, 0.95);
INITL::eval(K, L, L_center, 2u);
K.L2L(L2, L, L_center - L2_center);
// test L2P
K.L2P(L2, L2_center, t[0], rfmm);
#endif
// check errors
std::cout << "rexact = " << rexact[0] << std::endl;
std::cout << "rm2p = " << 1./6*rm2p << std::endl;
std::cout << "rfmm = " << 1./6*rfmm << std::endl;
/*
std::cout << "M2P L1 rel error: "
<< std::scientific << l1_rel_error(rm2p, rexact) << std::endl;
std::cout << "M2P L2 error: "
<< std::scientific << l2_error(rm2p, rexact) << std::endl;
std::cout << "M2P L2 rel error: "
<< std::scientific << l2_rel_error(rm2p, rexact) << std::endl;
#ifndef TREECODE_ONLY
std::cout << "FMM L1 rel error: "
<< std::scientific << l1_rel_error(rfmm, rexact) << std::endl;
std::cout << "FMM L2 error: "
<< std::scientific << l2_error(rfmm, rexact) << std::endl;
std::cout << "FMM L2 rel error: "
<< std::scientific << l2_rel_error(rfmm, rexact) << std::endl;
#endif
*/
}