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#include <getopt.h>
#include <iostream>
#include <chrono>
#include <fstream>
#define WOLFF_USE_FINITE_STATES
#include "wolff/lib/wolff_models/ising.hpp"
using namespace wolff;
class Timeseries : public measurement<ising_t, ising_t, graph<>> {
private:
signed M;
std::ofstream file;
public:
Timeseries(unsigned D, unsigned L, double T, double H, const wolff::system<ising_t, ising_t, graph<>>& S) : file("series.dat", std::ios::app) {
M = 0;
for (const ising_t& s : S.s) {
M = M + S.s0.act_inverse(s);
}
file << D << " " << L << " " << T << " " << H << " " << M;
}
~Timeseries() {
file << "\n";
file.close();
}
void ghost_bond_visited(const wolff::system<ising_t, ising_t, graph<>>&, const typename graph<>::vertex&,
const ising_t& s_old, const ising_t& s_new, double dE) override {
M += s_new - s_old;
}
void post_cluster(unsigned, unsigned, const wolff::system<ising_t, ising_t, graph<>>& S) override {
file << " " << M;
}
};
int main(int argc, char *argv[]) {
// set defaults
unsigned N = (unsigned)1e4;
unsigned D = 2;
unsigned L = 128;
double T = 2.26918531421;
double H = 0.0;
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': // external 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
auto seed = std::chrono::high_resolution_clock::now().time_since_epoch().count();
std::mt19937 rng(seed);
// 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
Timeseries A(D, L, T, H, S);
// run wolff N times
S.run_wolff(N, gen_r, A, rng);
// exit
return 0;
}
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