rewrote wolff in c++ with templates so that any system can be run with it

5 files changed, 363 insertions, 333 deletions

diff --git a/lib/cluster.c b/lib/cluster.c
deleted file mode 100644
index 96225a2..0000000
--- a/lib/cluster.c
+++ /dev/null
@@ -1,277 +0,0 @@
-
-#include "cluster.h"
-
-v_t flip_cluster_dgm(dgm_state_t *s, v_t v0, h_t rot, gsl_rng *r) {
-  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(s->g->nv, sizeof(bool));
-
-  while (stack != NULL) {
-    v_t v = stack_pop(&stack);
-
-    if (!marks[v]) {
-      h_t s_old, s_new;
-      dihinf_t *R_new; 
-      bool external_flipped;
-
-      marks[v] = true;
-
-      if (v == s->g->nv - 1) {
-        R_new = dihinf_compose(rot, s->R);
-        external_flipped = true;
-      } else {
-        s_old = s->spins[v];
-        s_new = dihinf_act(rot, s_old);
-        external_flipped = false;
-      }
-
-      v_t nn = s->g->v_i[v + 1] - s->g->v_i[v];
-
-      for (v_t i = 0; i < nn; i++) {
-        h_t sn;
-        double prob;
-        bool external_neighbor = false;
-
-        v_t vn = s->g->v_adj[s->g->v_i[v] + i];
-
-        if (vn == s->g->nv - 1) {
-          external_neighbor = true;
-        } else {
-          sn = s->spins[vn];
-        }
-
-        if (external_flipped || external_neighbor) {
-          h_t rot_s_old, rot_s_new;
-
-          if (external_neighbor) {
-            rot_s_old = dihinf_inverse_act(s->R, s_old);
-            rot_s_new = dihinf_inverse_act(s->R, s_new);
-          } else {
-            rot_s_old = dihinf_inverse_act(s->R, sn);
-            rot_s_new = dihinf_inverse_act(R_new, sn);
-          }
-
-          double dE = s->H(s->H_info, rot_s_old) - s->H(s->H_info, rot_s_new);
-          prob = 1.0 - exp(-dE / s->T);
-
-          s->M += rot_s_new - rot_s_old;
-          s->E += dE;
-        } else {
-          double dE = (s->J)(s_old - sn) - (s->J)(s_new - sn);
-          prob = 1.0 - exp(-dE / s->T);
-          s->E += dE;
-        }
-
-        if (gsl_rng_uniform(r) < prob) { // and with probability ps[e]...
-          stack_push(&stack, vn); // push the neighboring vertex to the stack
-        }
-      }
-
-      if (external_flipped) {
-        free(s->R);
-        s->R = R_new;
-      } else {
-        s->spins[v] = s_new;
-      }
-
-      if (v != s->g->nv - 1) { // count the number of non-external sites that flip
-        nv++;
-      }
-    }
-  }
-
-  free(marks);
-
-  return nv;
-}
-
-v_t flip_cluster_vector(vector_state_t *s, v_t v0, double *rot, gsl_rng *r) {
-  v_t nv = 0;
-
-  ll_t *stack = NULL;     // create a new stack
-  stack_push(&stack, v0); // push the initial vertex to the stack
-
-  //node_t *T = NULL;
-  bool *marks = (bool *)calloc(s->g->nv, sizeof(bool));
-
-  while (stack != NULL) {
-    v_t v = stack_pop(&stack);
-
-//    if (!tree_contains(T, v)) { // if the vertex hasn't already been flipped
-    if (!marks[v]) {
-      bool v_is_external = false;
-      double *s_old, *s_new, *R_tmp; 
-
-      if (v == s->g->nv - 1) {
-        v_is_external = true;
-      }
-
-      //tree_insert(&T, v);
-      marks[v] = true;
-
-      if (v == s->g->nv - 1) {
-        R_tmp = orthogonal_rotate(s->n, rot, s->R);
-      } else {
-        s_old = &(s->spins[s->n * v]); // don't free me! I'm a pointer within array s->spins
-        s_new = vector_rotate(s->n, rot, s_old); // free me! I'm a new vector
-      }
-
-      v_t nn = s->g->v_i[v + 1] - s->g->v_i[v];
-
-      for (v_t i = 0; i < nn; i++) {
-        v_t vn = s->g->v_adj[s->g->v_i[v] + i];
-
-        bool vn_is_external = false;
-
-        if (vn == s->g->nv - 1) {
-          vn_is_external = true;
-        }
-
-        double *sn;
-
-        if (!vn_is_external) {
-          sn = &(s->spins[s->n * vn]);
-        }
-
-        double prob;
-
-        if (v_is_external || vn_is_external) {
-          double *rs_old, *rs_new;
-          if (vn_is_external) {
-            rs_old = vector_rotate_inverse(s->n, s->R, s_old);
-            rs_new = vector_rotate_inverse(s->n, s->R, s_new);
-          } else {
-            rs_old = vector_rotate_inverse(s->n, s->R, sn);
-            rs_new = vector_rotate_inverse(s->n, R_tmp, sn);
-          }
-          double dE = s->H(s->n, s->H_info, rs_old) - s->H(s->n, s->H_info, rs_new);
-          prob = 1.0 - exp(-dE / s->T);
-          vector_subtract(s->n, s->M, rs_old);
-          vector_add(s->n, s->M, rs_new);
-          s->E += dE;
-
-          free(rs_old);
-          free(rs_new);
-        } else {
-          double dE = (s->J)(vector_dot(s->n, sn, s_old)) - (s->J)(vector_dot(s->n, sn, s_new));
-          prob = 1.0 - exp(-dE / s->T);
-          s->E += dE;
-        }
-
-        if (gsl_rng_uniform(r) < prob) { // and with probability ps[e]...
-          stack_push(&stack, vn); // push the neighboring vertex to the stack
-        }
-      }
-
-      if (v == s->g->nv - 1) {
-        free(s->R);
-        s->R = R_tmp;
-      } else {
-        vector_replace(s->n, s_old, s_new);
-        free(s_new);
-      }
-
-      if (v != s->g->nv - 1) { // count the number of non-external sites that flip
-        nv++;
-      }
-    }
-  }
-
-  //tree_freeNode(T);
-  free(marks);
-
-  return nv;
-}
-
-/*G
-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 *s0_old, *s0_new;
-
-      si_old = state->s[v];
-      s0_old = state->s0;
-
-      marks[v] = true;
-
-      if (v == state->g->nv - 1) {
-        s0_new = act <R_t, R_t> (r, s0_old);
-      } else {
-        si_new = act <R_t, X_t> (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->s[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 = inverse_act <class R_t, class X_t> (s0_old, si_old);
-            rs_new = inverse_act <class R_t, class X_t> (s0_old, si_new);
-          } else {
-            rs_old = inverse_act <class R_t, class X_t> (s0_old, sj);
-            rs_new = inverse_act <class R_t, class X_t> (s0_new, sj);
-          }
-          double dE = state->B(rs_old) - state->B(rs_new);
-          prob = 1.0 - exp(-dE / state->T);
-          update_magnetization <X_t> (state->M, rs_old, rs_new);
-          state->E += dE;
-
-          free_X <X_t> (rs_old);
-          free_X <X_t> (rs_new);
-        } else {
-          double dE = state->Z(si_old, sj) - state->Z(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_R <R_t> (state->s0);
-        state->s0 = s0_new;
-      } else {
-        free_X <X_t> (state->s[v]);
-        state->s[v] = si_new;
-      }
-
-      if (v != state->g->nv - 1) { // count the number of non-external sites that flip
-        nv++;
-      }
-    }
-  }
-
-  free(marks);
-
-  return nv;
-}
-*/
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;
+}
 
diff --git a/lib/graph.h b/lib/graph.h
index cb47faa..beb7f4c 100644
--- a/lib/graph.h
+++ b/lib/graph.h
@@ -7,6 +7,10 @@
 
 #include "types.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 typedef struct {
   v_t ne;
   v_t nv;
@@ -15,8 +19,10 @@ typedef struct {
 } graph_t;
 
 graph_t *graph_create_square(D_t D, L_t L);
-
 graph_t *graph_add_ext(const graph_t *G);
-
 void graph_free(graph_t *h);
 
+#ifdef __cplusplus
+}
+#endif
+
diff --git a/lib/rand.h b/lib/rand.h
index 2354f6a..7bb5354 100644
--- a/lib/rand.h
+++ b/lib/rand.h
@@ -4,4 +4,13 @@
 #include <assert.h>
 #include <stdio.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 unsigned long int rand_seed();
+
+#ifdef __cplusplus
+}
+#endif
+
diff --git a/lib/stack.h b/lib/stack.h
index a354ab5..8d25aff 100644
--- a/lib/stack.h
+++ b/lib/stack.h
@@ -8,6 +8,11 @@
 
 #include "types.h"
 
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 typedef struct ll_tag {
   v_t x;
   struct ll_tag *next;
@@ -24,3 +29,7 @@ void stack_push_d(dll_t **q, double x);
 v_t stack_pop(ll_t **q);
 double stack_pop_d(dll_t **q);
 
+#ifdef __cplusplus
+}
+#endif
+