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#include <getopt.h>
#include <iostream>
#include <chrono>
#define WOLFF_SITE_DEPENDENCE
#include <wolff_models/ising.hpp>
#include "simple_measurement.hpp"
using namespace wolff;
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);
};
// initialize the lattice. vertex_prop is set to double and will contain the
// value of the random field at that site
graph<double> G(D, L);
// initialize the random number generator
auto seed = std::chrono::high_resolution_clock::now().time_since_epoch().count();
std::mt19937 rng(seed);
// define the spin-field coupling
std::normal_distribution<double> distribution(0.0, H);
for (auto &v : G.vertices) {
v.prop = distribution(rng);
}
std::function <double(const graph<double>::vertex&, const ising_t&)> B = [] (const graph<double>::vertex& v, const ising_t& s) -> double {
return v.prop * s;
};
// initialize the system
wolff::system<ising_t, ising_t, graph<double>> S(G, T, Z, B);
// define function that generates self-inverse rotations
std::function <ising_t(std::mt19937&, const wolff::system<ising_t, ising_t, graph<double>>&, const graph<double>::vertex&)> gen_r = gen_ising<graph<double>>;
// initailze the measurement object
simple_measurement A(S);
// run wolff N times
S.run_wolff(N, gen_r, A, rng);
// print the result of our measurements
std::cout << "Wolff complete!\nThe average energy per site was " << A.avgE() / S.nv
<< ".\nThe average magnetization per site was " << A.avgM() / S.nv
<< ".\nThe average cluster size per site was " << A.avgC() / S.nv << ".\n";
// exit
return 0;
}
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