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-rw-r--r--src/wolff_clock.cpp154
1 files changed, 154 insertions, 0 deletions
diff --git a/src/wolff_clock.cpp b/src/wolff_clock.cpp
new file mode 100644
index 0000000..e186c44
--- /dev/null
+++ b/src/wolff_clock.cpp
@@ -0,0 +1,154 @@
+
+#include <getopt.h>
+
+#ifdef HAVE_GLUT
+#include <GL/glut.h>
+#endif
+
+// include your group and spin space
+#include <dihedral.h>
+#include <potts.h>
+#include <colors.h>
+
+// hack to speed things up considerably
+#define N_STATES POTTSQ
+#include <finite_states.h>
+
+// include wolff.h
+#include <rand.h>
+#include <wolff.h>
+
+typedef state_t <dihedral_t<q_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
+ gsl_rng *r = gsl_rng_alloc(gsl_rng_mt19937);
+ gsl_rng_set(r, rand_seed());
+
+ // define spin-spin coupling
+ std::function <double(potts_t<POTTSQ>, potts_t<POTTSQ>)> Z = [] (potts_t<POTTSQ> s1, 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(potts_t<POTTSQ>)> B = [=] (potts_t<POTTSQ> s) -> double {
+ return H_vec[s.x];
+ };
+
+ // initialize state object
+ state_t <dihedral_t<q_t,POTTSQ>, potts_t<POTTSQ>> s(D, L, T, Z, B);
+
+ // define function that generates self-inverse rotations
+ std::function <dihedral_t<q_t,POTTSQ>(gsl_rng *, potts_t<POTTSQ>)> gen_R = [] (gsl_rng *r, potts_t<POTTSQ> v) -> dihedral_t<q_t,POTTSQ> {
+ dihedral_t<q_t,POTTSQ> rot;
+ rot.is_reflection = true;
+ q_t x = gsl_rng_uniform_int(r, POTTSQ - 1);
+ 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 = act_inverse(s->R, 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, r, 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
+ gsl_rng_free(r);
+
+ if (draw) {
+ }
+
+ return 0;
+
+}
+