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#include <fstream>
#include <getopt.h>
#include "randutils/randutils.hpp"
#define WOLFF_USE_FINITE_STATES
#include "wolff/lib/wolff_models/ising.hpp"
using namespace wolff;
class sample : public measurement<ising_t, ising_t, graph<>> {
private:
typedef struct _dat {
int e;
int m;
} dat;
std::ofstream e_file;
dat e;
public:
sample(const wolff::system<ising_t, ising_t, graph<>>& s, unsigned D, unsigned L, double T,
double H) {
e_file.open("sample_" + std::to_string(D) + "_" + std::to_string(L) + "_" + std::to_string(T) +
"_" + std::to_string(H) + ".bin",
std::ios::out | std::ios::binary | std::ios::app);
e.e = -s.ne;
e.m = s.nv;
}
~sample() { e_file.close(); }
void ghost_bond_visited(const system<ising_t, ising_t, graph<>>&, const typename graph<>::vertex&,
const ising_t& s_old, const ising_t& s_new, double dE) override {
e.m += s_new - s_old;
}
void plain_bond_visited(const wolff::system<ising_t, ising_t, graph<>>& s,
const typename graph<>::halfedge& ed, const ising_t& si_new,
double dE) override {
e.e -= 2 * (si_new * s.s[ed.neighbor.ind]);
}
void post_cluster(unsigned n, unsigned,
const wolff::system<ising_t, ising_t, graph<>>&) override {
e_file.write((char*)&e, 2 * sizeof(int));
}
};
int main(int argc, char* argv[]) {
// set defaults
unsigned N = (unsigned)1e4;
unsigned D = 2;
unsigned L = 128;
double T = 2 / log(1 + sqrt(2));
double H = 0;
int opt;
// take command line arguments
while ((opt = getopt(argc, argv, "N:D:L:T:H:")) != -1) {
switch (opt) {
case 'N': // number of steps
N = (unsigned)atof(optarg);
break;
case 'D': // dimension
D = atoi(optarg);
break;
case 'L': // linear size
L = atoi(optarg);
break;
case 'T': // temperature
T = atof(optarg);
break;
case 'H': // field
H = atof(optarg);
break;
default:
exit(EXIT_FAILURE);
}
}
// define the spin-spin coupling
std::function<double(const ising_t&, const ising_t&)> Z =
[](const ising_t& s1, const ising_t& s2) -> double { return (double)(s1 * s2); };
// define the spin-field coupling
std::function<double(const ising_t&)> B = [=](const ising_t& s) -> double { return H * s; };
// initialize the lattice
graph<> G(D, L);
// initialize the system
wolff::system<ising_t, ising_t, graph<>> S(G, T, Z, B);
// initialize the random number generator
randutils::auto_seed_128 seeds;
std::mt19937 rng{seeds};
// define function that generates self-inverse rotations
std::function<ising_t(std::mt19937&, const wolff::system<ising_t, ising_t, graph<>>&,
const graph<>::vertex&)>
gen_r = gen_ising<graph<>>;
// initailze the measurement object
sample A(S, D, L, T, H);
// run wolff N times
S.run_wolff(N, gen_r, A, rng);
// exit
return 0;
}
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