1 files changed, 337 insertions, 54 deletions

diff --git a/lib/cluster.h b/lib/cluster.h
index d118735..29dd0cb 100644
--- a/lib/cluster.h
+++ b/lib/cluster.h
@@ -1,13 +1,14 @@
 
 #pragma once
 
+#include <functional>
 #include <assert.h>
 #include <fftw3.h>
 #include <float.h>
 #include <gsl/gsl_randist.h>
 #include <gsl/gsl_rng.h>
 #include <inttypes.h>
-#include <math.h>
+#include <cmath>
 #include <stdbool.h>
 #include <string.h>
 #include <sys/types.h>
@@ -24,57 +25,339 @@
 #include "dihinf.h"
 #include "yule_walker.h"
 
-typedef struct {
-  graph_t *g;
-  q_t *spins;
-  double T;
-  double *J;
-  double *H;
-  double *J_probs;
-  double *H_probs;
-  dihedral_t *R;
-  double E;
-  v_t *M;
-  q_t q;
-} ising_state_t;
-
-typedef struct {
-  graph_t *g;
-  h_t *spins;
-  double T;
-  double (*J)(h_t);
-  double (*H)(double *, h_t);
-  double *H_info;
-  dihinf_t *R;
-  double E;
-  h_t M;
-} dgm_state_t;
-
-typedef struct {
-  graph_t *g;
-  double *spins;
-  double T;
-  double (*J)(double);
-  double (*H)(q_t, double *, double *);
-  double *H_info;
-  double *R;
-  double E;
-  double *M;
-  q_t n;
-} vector_state_t;
-
-typedef enum {
-  VECTOR,
-  MODULATED,
-  CUBIC,
-  QUADRATIC
-} vector_field_t;
-
-v_t flip_cluster(ising_state_t *s, v_t v0, q_t s1, gsl_rng *r);
-
-v_t flip_cluster_vector(vector_state_t *s, v_t v0, double *rot, gsl_rng *r);
-
-v_t flip_cluster_dgm(dgm_state_t *s, v_t v0, h_t rot, gsl_rng *r);
-
-graph_t *graph_add_ext(const graph_t *g);
+template <class T>
+void init(T*);
+
+template <class T>
+T scalar_multiple(v_t a, T b);
+
+template <class R_t, class X_t>
+X_t act(R_t a, X_t b);
+
+template <class R_t, class X_t>
+X_t act_inverse(R_t a, X_t b);
+
+template <class T>
+T copy(T a);
+
+template <class T>
+void free_spin(T a);
+
+template <class T>
+T add(T, T);
+
+template <class T>
+T subtract(T, T);
+
+template <class T>
+T gen_rot(gsl_rng *r);
+
+template <class R_t, class X_t>
+class state_t {
+  public:
+    D_t D;
+    L_t L;
+    v_t nv;
+    v_t ne;
+    graph_t *g;
+    double T;
+    X_t *spins;
+    R_t R;
+    double E;
+    X_t M; // the "sum" of the spins, like the total magnetization
+
+    std::function <double(X_t, X_t)> J;
+    std::function <double(X_t)> H;
+
+    state_t(D_t D, L_t L, double T, std::function <double(X_t, X_t)> J, std::function <double(X_t)> H) : D(D), L(L), T(T), J(J), H(H) {
+      graph_t *h = graph_create_square(D, L);
+      nv = h->nv;
+      ne = h->ne;
+      g = graph_add_ext(h);
+      graph_free(h);
+      spins = (X_t *)malloc(nv * sizeof(X_t));
+      for (v_t i = 0; i < nv; i++) {
+        init (&(spins[i]));
+      }
+      init (&R);
+      E = - (double)ne * J(spins[0], spins[0]) - (double)nv * H(spins[0]);
+      M = scalar_multiple (nv, spins[0]);
+    }
+
+    ~state_t() {
+      graph_free(g);
+      for (v_t i = 0; i < nv; i++) {
+        free_spin(spins[i]);
+      }
+      free(spins);
+      free_spin(R);
+      free_spin(M);
+    }
+};
+
+template <q_t q, class T>
+struct vector_t { T *x; };
+
+template <q_t q, class T>
+void init(vector_t <q, T> *ptr) {
+  ptr->x = (T *)calloc(q, sizeof(T));
+
+  ptr->x[0] = (T)1;
+}
+
+template <q_t q, class T>
+vector_t <q, T> copy (vector_t <q, T> v) {
+  vector_t <q, T> v_copy;
+ 
+ v_copy.x = (T *)calloc(q, sizeof(T));
+
+  for (q_t i = 0; i < q; i++) {
+    v_copy.x[i] = v.x[i];
+  }
+
+  return v_copy;
+}
+
+template <q_t q, class T>
+void add (vector_t <q, T> v1, vector_t <q, T> v2) {
+  for (q_t i = 0; i < q; i++) {
+    v1.x[i] += v2.x[i];
+  }
+}
+
+template <q_t q, class T>
+void subtract (vector_t <q, T> v1, vector_t <q, T> v2) {
+  for (q_t i = 0; i < q; i++) {
+    v1.x[i] -= v2.x[i];
+  }
+}
+
+template <q_t q, class T>
+vector_t <q, T> scalar_multiple(v_t a, vector_t <q, T> v) {
+  vector_t <q, T> multiple;
+  multiple.x = (T *)malloc(q * sizeof(T));
+  for (q_t i = 0; i < q; i++) {
+    multiple.x[i] = a * v.x[i];
+  }
+
+  return multiple;
+}
+
+template <q_t q, class T>
+T dot(vector_t <q, T> v1, vector_t <q, T> v2) {
+  T prod = 0;
+
+  for (q_t i = 0; i < q; i++) {
+    prod += v1.x[i] * v2.x[i];
+  }
+
+  return prod;
+}
+
+template <q_t q, class T>
+void free_spin (vector_t <q, T> v) {
+  free(v.x);
+}
+
+template <q_t q, class T>
+struct orthogonal_t { T *x; };
+
+template <q_t q, class T>
+void init(orthogonal_t <q, T> *ptr) {
+  ptr->x = (T *)calloc(q * q, sizeof(T));
+
+  for (q_t i = 0; i < q; i++) {
+    ptr->x[q * i + i] = (T)1;
+  }
+}
+
+template <q_t q, class T>
+orthogonal_t <q, T> copy (orthogonal_t <q, T> m) {
+  orthogonal_t <q, T> m_copy;
+  m_copy.x = (T *)calloc(q * q, sizeof(T));
+
+  for (q_t i = 0; i < q * q; i++) {
+    m_copy.x[i] = m.x[i];
+  }
+
+  return m_copy;
+}
+
+template <q_t q, class T>
+void free_spin (orthogonal_t <q, T> m) {
+  free(m.x);
+}
+
+template <q_t q, class T>
+vector_t <q, T> act (orthogonal_t <q, T> m, vector_t <q, T> v) {
+  vector_t <q, T> v_rot;
+  v_rot.x = (T *)calloc(q, sizeof(T));
+
+  for (q_t i = 0; i < q; i++) {
+    for (q_t j = 0; j < q; j++) {
+      v_rot.x[i] += m.x[q * i + j] * v.x[j];
+    }
+  }
+
+  return v_rot;
+}
+
+
+template <q_t q, class T>
+orthogonal_t <q, T> act (orthogonal_t <q, T> m1, orthogonal_t <q, T> m2) {
+  orthogonal_t <q, T> m2_rot;
+  m2_rot.x = (T *)calloc(q * q, sizeof(T));
+
+  for (q_t i = 0; i < q; i++) {
+    for (q_t j = 0; j < q; j++) {
+      for (q_t k = 0; k < q; k++) {
+        m2_rot.x[i * q + j] += m1.x[i * q + j] * m2.x[j * q + k];
+      }
+    }
+  }
+
+  return m2_rot;
+}
+
+template <q_t q, class T>
+vector_t <q, T> act_inverse (orthogonal_t <q, T> m, vector_t <q, T> v) {
+  vector_t <q, T> v_rot;
+  v_rot.x = (T *)calloc(q, sizeof(T));
+
+  for (q_t i = 0; i < q; i++) {
+    for (q_t j = 0; j < q; j++) {
+      v_rot.x[i] += m.x[q * j + i] * v.x[j];
+    }
+  }
+
+  return v_rot;
+}
+
+template <q_t q, class T>
+orthogonal_t <q, T> act_inverse (orthogonal_t <q, T> m1, orthogonal_t <q, T> m2) {
+  orthogonal_t <q, T> m2_rot;
+  m2_rot.x = (T *)calloc(q * q, sizeof(T));
+
+  for (q_t i = 0; i < q; i++) {
+    for (q_t j = 0; j < q; j++) {
+      for (q_t k = 0; k < q; k++) {
+        m2_rot.x[i * q + j] += m1.x[j * q + i] * m2.x[j * q + k];
+      }
+    }
+  }
+
+  return m2_rot;
+}
+
+template <q_t q>
+void generate_rotation (gsl_rng *r, orthogonal_t <q, double> *ptr) {
+  double *v = (double *)malloc(q * sizeof(double));
+  double v2 = 0;
+
+  for (q_t i = 0; i < q; i++) {
+    v[i] = gsl_ran_ugaussian(r);
+    v2 += v[i] * v[i];
+  }
+
+  ptr->x = (double *)calloc(q * q, sizeof(double));
+  
+  for (q_t i = 0; i < q; i++) {
+    ptr->x[q * i + i] = 1.0;
+    for (q_t j = 0; j < q; j++) {
+      ptr->x[q * i + j] -= 2 * v[i] * v[j] / v2;
+    }
+  }
+
+  free(v);
+}
+
+template <class R_t, class X_t>
+v_t flip_cluster(state_t <R_t, X_t> *state, v_t v0, R_t r, gsl_rng *rand) {
+  v_t nv = 0;
+
+  ll_t *stack = NULL;     // create a new stack
+  stack_push(&stack, v0); // push the initial vertex to the stack
+
+  bool *marks = (bool *)calloc(state->g->nv, sizeof(bool));
+
+  while (stack != NULL) {
+    v_t v = stack_pop(&stack);
+
+    if (!marks[v]) {
+      X_t si_old, si_new;
+      R_t R_old, R_new;
+
+      si_old = state->spins[v];
+      R_old = state->R;
+
+      marks[v] = true;
+
+      if (v == state->g->nv - 1) {
+        R_new = act (r, R_old);
+      } else {
+        si_new = act (r, si_old);
+      }
+
+      v_t nn = state->g->v_i[v + 1] - state->g->v_i[v];
+
+      for (v_t i = 0; i < nn; i++) {
+        v_t vn = state->g->v_adj[state->g->v_i[v] + i];
+
+        X_t sj;
+
+        if (vn != state->g->nv - 1) {
+          sj = state->spins[vn];
+        }
+
+        double prob;
+
+        bool is_ext = (v == state->g->nv - 1 || vn == state->g->nv - 1);
+
+        if (is_ext) {
+          X_t rs_old, rs_new;
+          if (vn == state->g->nv - 1) {
+            rs_old = act_inverse (R_old, si_old);
+            rs_new = act_inverse (R_old, si_new);
+          } else {
+            rs_old = act_inverse (R_old, sj);
+            rs_new = act_inverse (R_new, sj);
+          }
+          double dE = state->H(rs_old) - state->H(rs_new);
+          prob = 1.0 - exp(-dE / state->T);
+
+          subtract (state->M, rs_old);
+          add (state->M, rs_new);
+          state->E += dE;
+
+          free_spin (rs_old);
+          free_spin (rs_new);
+        } else {
+          double dE = state->J(si_old, sj) - state->J(si_new, sj);
+          prob = 1.0 - exp(-dE / state->T);
+          state->E += dE;
+        }
+
+        if (gsl_rng_uniform(rand) < prob) { // and with probability...
+          stack_push(&stack, vn); // push the neighboring vertex to the stack
+        }
+      }
+
+      if (v == state->g->nv - 1) {
+        free_spin(state->R);
+        state->R = R_new;
+      } else {
+        free_spin(state->spins[v]);
+        state->spins[v] = si_new;
+      }
+
+      if (v != state->g->nv - 1) { // count the number of non-external sites that flip
+        nv++;
+      }
+    }
+  }
+
+  free(marks);
+
+  return nv;
+}