implemented the discrete gaussian model for roughening

4 files changed, 180 insertions, 12 deletions

diff --git a/src/wolff_On.cpp b/src/wolff_On.cpp
index a59876f..9f95f4a 100644
--- a/src/wolff_On.cpp
+++ b/src/wolff_On.cpp
@@ -125,7 +125,7 @@ int main(int argc, char *argv[]) {
 
   const char *pert_type;
 
-  std::function <orthogonal_R_t(gsl_rng *, const On_t *)> gen_R;
+  std::function <orthogonal_R_t(gsl_rng *, vector_R_t)> gen_R;
 
   if (use_pert) {
     gen_R = std::bind(generate_rotation_perturbation <N_COMP>, std::placeholders::_1, std::placeholders::_2, epsilon);
diff --git a/src/wolff_dgm.cpp b/src/wolff_dgm.cpp
new file mode 100644
index 0000000..6337a5e
--- /dev/null
+++ b/src/wolff_dgm.cpp
@@ -0,0 +1,168 @@
+
+#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 <wolff.h>
+
+typedef state_t <dihedral_inf_t<int64_t>, height_t<int64_t>> 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;
+  uint64_t 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<int64_t>, height_t<int64_t>)> Z = [] (height_t<int64_t> h1, height_t<int64_t> h2) -> double {
+    return -pow(h1.x - h2.x, 2);
+  };
+
+  // define spin-field coupling
+  std::function <double(height_t<int64_t>)> B = [=] (height_t<int64_t> 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<int64_t>(gsl_rng *, height_t<int64_t>)> gen_R = [=] (gsl_rng *r, height_t<int64_t> h) -> dihedral_inf_t<int64_t> {
+    dihedral_inf_t<int64_t> rot;
+    rot.is_reflection = true;
+
+    int direction = gsl_rng_uniform_int(r, 2);
+    int64_t amount = gsl_rng_uniform_int(r, epsilon);
+
+    if (direction == 0) {
+      rot.x = 2 * h.x + (1 + amount);
+    } else {
+      rot.x = 2 * h.x - (1 + 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
+
+    // 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);
+      int64_t max_h = INT64_MIN;
+      int64_t min_h = INT64_MAX;
+      for (v_t i = 0; i < pow(L, 2); i++) {
+        int64_t cur_h = act_inverse(s->R, 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++) {
+        int64_t cur_h = act_inverse(s->R, 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();
+    };
+  }
+
+  // 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;
+
+}
+
diff --git a/src/wolff_ising.cpp b/src/wolff_ising.cpp
index 83b6448..e072d6a 100644
--- a/src/wolff_ising.cpp
+++ b/src/wolff_ising.cpp
@@ -88,7 +88,7 @@ int main(int argc, char *argv[]) {
   state_t <z2_t, ising_t> s(D, L, T, Z, B);
 
   // define function that generates self-inverse rotations
-  std::function <z2_t(gsl_rng *, const state_t <z2_t, ising_t> *)> gen_R = [] (gsl_rng *, const state_t <z2_t, ising_t> *) -> z2_t {
+  std::function <z2_t(gsl_rng *, ising_t)> gen_R = [] (gsl_rng *, ising_t s) -> z2_t {
     z2_t rot;
     rot.x = true;
     return rot;
diff --git a/src/wolff_potts.cpp b/src/wolff_potts.cpp
index 3b55472..74e0ea9 100644
--- a/src/wolff_potts.cpp
+++ b/src/wolff_potts.cpp
@@ -90,21 +90,21 @@ int main(int argc, char *argv[]) {
   state_t <symmetric_t<POTTSQ>, potts_t<POTTSQ>> s(D, L, T, Z, B);
 
   // define function that generates self-inverse rotations
-  std::function <symmetric_t<POTTSQ>(gsl_rng *, const sim_t *)> gen_R = [] (gsl_rng *r, const sim_t *s) -> symmetric_t<POTTSQ> {
+  std::function <symmetric_t<POTTSQ>(gsl_rng *, potts_t<POTTSQ>)> gen_R = [] (gsl_rng *r, potts_t<POTTSQ> v) -> symmetric_t<POTTSQ> {
     symmetric_t<POTTSQ> rot;
     init(&rot);
 
-    for (int i = POTTSQ - 1; i >= 0; i--) {
-      if (rot.perm[i] == i) {
-        q_t j = gsl_rng_uniform_int(r, i + 1);
-        if (rot.perm[j] == j) {
-          q_t tmp = rot.perm[i];
-          rot.perm[i] = rot.perm[j];
-          rot.perm[j] = tmp;
-        }
-      }
+    q_t j = gsl_rng_uniform_int(r, POTTSQ - 1);
+    q_t swap_v;
+    if (j < v.x) {
+      swap_v = j;
+    } else {
+      swap_v = j + 1;
     }
 
+    rot.perm[v.x] = swap_v;
+    rot.perm[swap_v] = v.x;
+
     return rot;
   };