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#include <getopt.h>
#include <fstream>
#include "randutils/randutils.hpp"
#define WOLFF_NO_FIELD
#define WOLFF_USE_FINITE_STATES
#include "wolff/lib/wolff_models/ising.hpp"
#include "wolff/lib/wolff.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;
unsigned w;
unsigned N;
unsigned τ;
public:
sample(const wolff::system<ising_t, ising_t, graph<>> &s, unsigned D, unsigned L, double T, unsigned wait) {
e_file.open("sample_" + std::to_string(D) + "_" + std::to_string(L) + "_" + std::to_string(T) + ".bin" , std::ios::out | std::ios::binary | std::ios::app);
e.e = - s.ne;
e.m = s.nv;
N = 0;
τ = 2 * (unsigned)ceil(pow(L, 0.3));
w = wait;
}
~sample() {
e_file.close();
}
void plain_site_transformed(const wolff::system<ising_t, ising_t, graph<>>&, const typename graph<>::vertex&, const ising_t& si_new) override {
e.m += (unsigned)2 * si_new;
}
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 {
if (N >= w && (N - w) % τ == 0) {
e_file.write((char *)&e, 2 * sizeof(int));
}
N++;
}
};
int main(int argc, char *argv[]) {
// set defaults
unsigned N = (unsigned)1e4;
unsigned w = (unsigned)1e3;
unsigned D = 2;
unsigned L = 128;
double T = 2 / log(1 + sqrt(2));
int opt;
// take command line arguments
while ((opt = getopt(argc, argv, "N:D:L:T:w:")) != -1) {
switch (opt) {
case 'N': // number of steps
N = (unsigned)atof(optarg);
break;
case 'w': // number of steps
w = (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;
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);
};
// initialize the lattice
graph<> G(D, L);
// initialize the system
wolff::system<ising_t, ising_t, graph<>> S(G, T, Z);
// 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, w);
// run wolff N times
S.run_wolff(N, gen_r, A, rng);
// exit
return 0;
}
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