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#include <getopt.h>
#ifdef HAVE_GLUT
#include <GL/glut.h>
#endif
// include your group and spin space
#include <dihedral_inf.h>
#include <height.h>
// include wolff.h
#include <rand.h>
#include <wolff.h>
typedef state_t <dihedral_inf_t<double>, height_t<double>> 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 = 0;
bool silent = false;
bool draw = false;
unsigned int window_size = 512;
double epsilon = 1;
int opt;
while ((opt = getopt(argc, argv, "N:D:L:T:H:sdw:e:")) != -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 = atof(optarg);
break;
case 'e': // external field. nth call couples to state n
epsilon = atof(optarg);
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
gsl_rng *r = gsl_rng_alloc(gsl_rng_mt19937);
gsl_rng_set(r, rand_seed());
// define spin-spin coupling
std::function <double(height_t<double>, height_t<double>)> Z = [] (height_t<double> h1, height_t<double> h2) -> double {
return -pow(h1.x - h2.x, 2);
};
// define spin-field coupling
std::function <double(height_t<double>)> B = [=] (height_t<double> h) -> double {
return -H * pow(h.x, 2);;
};
// initialize state object
sim_t s(D, L, T, Z, B);
// define function that generates self-inverse rotations
std::function <dihedral_inf_t<double>(gsl_rng *, height_t<double>)> gen_R = [=] (gsl_rng *r, height_t<double> h) -> dihedral_inf_t<double> {
dihedral_inf_t<double> rot;
rot.is_reflection = true;
double amount = epsilon * gsl_ran_ugaussian(r);
rot.x = 2 * h.x + amount;
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 / (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 / (double)N / (double)s->nv;
glClear(GL_COLOR_BUFFER_BIT);
double max_h = INT64_MIN;
double min_h = INT64_MAX;
for (v_t i = 0; i < pow(L, 2); i++) {
double cur_h = (s->R.act_inverse(s->spins[i])).x;
if (cur_h < min_h) {
min_h = cur_h;
}
if (cur_h > max_h) {
max_h = cur_h;
}
}
for (v_t i = 0; i < pow(L, 2); i++) {
double cur_h = (s->R.act_inverse(s->spins[i])).x;
double mag = ((double)(cur_h - min_h)) / ((double)(max_h - min_h));
glColor3f(mag, mag, mag);
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, r, silent);
// tell us what we found!
printf("%" PRIcount " DGM runs completed. D = %" PRID ", L = %" PRIL ", T = %g, H = %g, <M> = %g\n", N, D, L, T, H, average_M);
// free the random number generator
gsl_rng_free(r);
if (draw) {
}
return 0;
}
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