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#include <getopt.h>
#ifdef HAVE_GLUT
#include <GL/glut.h>
#endif
// include your group and spin space
#include "dihedral.hpp"
#include "potts.hpp"
#include <colors.h>
// hack to speed things up considerably
#define N_STATES POTTSQ
#include <wolff/finite_states.hpp>
#include <randutils/randutils.hpp>
// include wolff.hpp
#include <wolff.hpp>
typedef state_t <dihedral_t<POTTSQ>, potts_t<POTTSQ>> sim_t;
int main(int argc, char *argv[]) {
count_t N = (count_t)1e4;
D_t D = 2;
L_t L = 128;
double T = 2.26918531421;
double *H_vec = (double *)calloc(MAX_Q, sizeof(double));
bool silent = false;
bool draw = false;
unsigned int window_size = 512;
int opt;
q_t H_ind = 0;
while ((opt = getopt(argc, argv, "N:D:L:T:H:sdw:")) != -1) {
switch (opt) {
case 'N': // number of steps
N = (count_t)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. nth call couples to state n
H_vec[H_ind] = atof(optarg);
H_ind++;
break;
case 's': // don't print anything during simulation. speeds up slightly
silent = true;
break;
case 'd':
#ifdef HAVE_GLUT
draw = true;
break;
#else
printf("You didn't compile this with the glut library installed!\n");
exit(EXIT_FAILURE);
#endif
case 'w':
window_size = atoi(optarg);
break;
default:
exit(EXIT_FAILURE);
}
}
// initialize random number generator
randutils::auto_seed_128 seeds;
std::mt19937 rng{seeds};
// define spin-spin coupling
std::function <double(const potts_t<POTTSQ>&, const potts_t<POTTSQ>&)> Z = [] (const potts_t<POTTSQ>& s1, const potts_t<POTTSQ>& s2) -> double {
return cos(2 * M_PI * (double)(s1.x + POTTSQ - s2.x) / (double)POTTSQ);
};
// define spin-field coupling
std::function <double(const potts_t<POTTSQ>&)> B = [=] (const potts_t<POTTSQ>& s) -> double {
return H_vec[s.x];
};
// initialize state object
state_t <dihedral_t<POTTSQ>, potts_t<POTTSQ>> s(D, L, T, Z, B);
// define function that generates self-inverse rotations
std::function <dihedral_t<POTTSQ>(std::mt19937&, potts_t<POTTSQ>)> gen_R = [] (std::mt19937& r, potts_t<POTTSQ> v) -> dihedral_t<POTTSQ> {
dihedral_t<POTTSQ> rot;
rot.is_reflection = true;
std::uniform_int_distribution<q_t> dist(0, POTTSQ - 1);
q_t x = dist(r);
rot.x = (2 * v.x + x + 1) % POTTSQ;
return rot;
};
// define function that updates any number of measurements
std::function <void(const sim_t&)> measurement;
double average_M = 0;
if (!draw) {
// a very simple example: measure the average magnetization
measurement = [&] (const sim_t& s) {
average_M += (double)s.M[0] / (double)N / (double)s.nv;
};
} else {
// a more complex example: measure the average magnetization, and draw the spin configuration to the screen
#ifdef HAVE_GLUT
// initialize glut
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
glutInitWindowSize(window_size, window_size);
glutCreateWindow("wolff");
glClearColor(0.0,0.0,0.0,0.0);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(0.0, L, 0.0, L);
measurement = [&] (const sim_t& s) {
average_M += (double)s.M[0] / (double)N / (double)s.nv;
glClear(GL_COLOR_BUFFER_BIT);
for (v_t i = 0; i < pow(L, 2); i++) {
potts_t<POTTSQ> tmp_s = s.R.act_inverse(s.spins[i]);
glColor3f(hue_to_R(tmp_s.x * 2 * M_PI / POTTSQ), hue_to_G(tmp_s.x * 2 * M_PI / POTTSQ), hue_to_B(tmp_s.x * 2 * M_PI / POTTSQ));
glRecti(i / L, i % L, (i / L) + 1, (i % L) + 1);
}
glFlush();
};
#endif
}
// run wolff for N cluster flips
wolff(N, s, gen_R, measurement, rng, silent);
// tell us what we found!
printf("%" PRIcount " %d-Potts runs completed. D = %" PRID ", L = %" PRIL ", T = %g, H = %g, <M> = %g\n", N, POTTSQ, D, L, T, H_vec[0], average_M);
// free the random number generator
if (draw) {
}
return 0;
}
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