many changes, including new spin spaces and groups and cleaning up core library code

7 files changed, 172 insertions, 13 deletions

diff --git a/lib/angle.h b/lib/angle.h
new file mode 100644
index 0000000..c3f128e
--- /dev/null
+++ b/lib/angle.h
@@ -0,0 +1,48 @@
+#pragma once
+
+#include "types.h"
+
+#include <cmath>
+#include "vector.h"
+
+class angle_t {
+  public:
+    double x;
+
+    typedef vector_t<2, double> M_t;
+    typedef vector_t<2, double> F_t;
+
+    angle_t() : x(0) {}
+    angle_t(double x) : x(x) {}
+
+    inline vector_t<2, double> operator*(v_t a) const {
+      vector_t<2, double>M;
+      M[0] = a * cos(x);
+      M[1] = a * sin(x);
+
+      return M;
+    }
+
+    inline vector_t<2, double> operator*(double a) const {
+      vector_t<2, double>M;
+      M[0] = a * cos(x);
+      M[1] = a * sin(x);
+
+      return M;
+    }
+};
+
+inline vector_t<2,double>& operator+=(vector_t<2,double>& M, const angle_t& theta) {
+  M[0] += cos(theta.x);
+  M[1] += sin(theta.x);
+
+  return M;
+}
+
+inline vector_t<2,double>& operator-=(vector_t<2,double>& M, const angle_t& theta) {
+  M[0] -= cos(theta.x);
+  M[1] -= sin(theta.x);
+
+  return M;
+}
+
diff --git a/lib/circle_group.h b/lib/circle_group.h
new file mode 100644
index 0000000..cb7cadd
--- /dev/null
+++ b/lib/circle_group.h
@@ -0,0 +1,46 @@
+#pragma once
+
+#include "angle.h"
+
+class circle_group_t {
+  public:
+    bool is_reflection;
+    double x;
+
+    circle_group_t() : is_reflection(false), x(0) {}
+    circle_group_t(bool x, double y) : is_reflection(x), x(y) {}
+
+    angle_t act(const angle_t& theta) const {
+      if (is_reflection) {
+        return angle_t(fmod(2 * M_PI + x - theta.x, 2 * M_PI));
+      } else {
+        return angle_t(fmod(x + theta.x, 2 * M_PI));
+      }
+    }
+
+    circle_group_t act(const circle_group_t& r) const {
+      if (is_reflection) {
+        return circle_group_t(!r.is_reflection, fmod(2 * M_PI + x - r.x, 2 * M_PI));
+      } else {
+        return circle_group_t(r.is_reflection, fmod(x + r.x, 2 * M_PI));
+      }
+    }
+
+    angle_t act_inverse(const angle_t& theta) const {
+      if (is_reflection) {
+        return act(theta);
+      } else {
+        return angle_t(fmod(2 * M_PI + theta.x - x, 2 * M_PI));
+      }
+    }
+
+    circle_group_t act_inverse(const circle_group_t& r) const {
+      if (is_reflection) {
+        return act(r);
+      } else {
+        return circle_group_t(r.is_reflection, fmod(2 * M_PI + r.x - x, 2 * M_PI));
+      }
+    }
+};
+
+
diff --git a/lib/cluster.h b/lib/cluster.h
index c5f2be7..f948586 100644
--- a/lib/cluster.h
+++ b/lib/cluster.h
@@ -31,7 +31,9 @@ void flip_cluster(state_t <R_t, X_t> *state, v_t v0, R_t r, gsl_rng *rand) {
       R_old = state->R;
       marks[v] = true;
 
-      if (v == state->nv) {
+      bool v_is_ghost = (v == state->nv);
+
+      if (v_is_ghost) {
         R_new = r.act(R_old);
       } else {
         si_old = state->spins[v];
@@ -40,19 +42,18 @@ void flip_cluster(state_t <R_t, X_t> *state, v_t v0, R_t r, gsl_rng *rand) {
 
       for (const v_t &vn : state->g.v_adj[v]) {
         X_t sj;
+        bool vn_is_ghost = (vn == state->nv);
 
-        if (vn != state->nv) {
+        if (!vn_is_ghost) {
           sj = state->spins[vn];
         }
 
         double prob;
 
-        bool is_ext = (v == state->nv || vn == state->nv);
-
-        if (is_ext) {
+        if (v_is_ghost || vn_is_ghost) {
           X_t rs_old, rs_new;
           v_t non_ghost;
-          if (vn == state->nv) {
+          if (vn_is_ghost) {
             rs_old = R_old.act_inverse(si_old);
             rs_new = R_old.act_inverse(si_new);
             non_ghost = v;
@@ -61,6 +62,7 @@ void flip_cluster(state_t <R_t, X_t> *state, v_t v0, R_t r, gsl_rng *rand) {
             rs_new = R_new.act_inverse(sj);
             non_ghost = vn;
           }
+
           double dE = state->H(rs_old) - state->H(rs_new);
 #ifdef FINITE_STATES
           prob = H_probs[state_to_ind(rs_old)][state_to_ind(rs_new)];
@@ -97,7 +99,7 @@ void flip_cluster(state_t <R_t, X_t> *state, v_t v0, R_t r, gsl_rng *rand) {
         }
       }
 
-      if (v == state->nv) {
+      if (v_is_ghost) {
         state->R = R_new;
       } else {
         state->spins[v] = si_new;
diff --git a/lib/dihedral.h b/lib/dihedral.h
index 5588afa..8d0472b 100644
--- a/lib/dihedral.h
+++ b/lib/dihedral.h
@@ -21,7 +21,6 @@ class dihedral_t {
       }
     }
 
-
     dihedral_t<q> act(dihedral_t<q> r) const {
       if (this->is_reflection) {
         return dihedral_t<q>(!(r.is_reflection), ((q + this->x) - r.x) % q); 
diff --git a/lib/state.h b/lib/state.h
index eefa0cb..5abf65b 100644
--- a/lib/state.h
+++ b/lib/state.h
@@ -27,10 +27,10 @@ class state_t {
     std::vector<double> precomputed_cos;
     std::vector<double> precomputed_sin;
 
-    std::function <double(X_t, X_t)> J;
-    std::function <double(X_t)> H;
+    std::function <double(const X_t&, const X_t&)> J;
+    std::function <double(const 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), g(D, L), T(T), R(), J(J), H(H) {
+    state_t(D_t D, L_t L, double T, std::function <double(const X_t&, const X_t&)> J, std::function <double(const X_t&)> H) : D(D), L(L), g(D, L), T(T), R(), J(J), H(H) {
       nv = g.nv;
       ne = g.ne;
       g.add_ext();
diff --git a/lib/torus.h b/lib/torus.h
new file mode 100644
index 0000000..2aead52
--- /dev/null
+++ b/lib/torus.h
@@ -0,0 +1,64 @@
+
+#pragma once
+
+#include <cmath>
+#include <array>
+#include "types.h"
+
+template <q_t n>
+class torus_t : public std::array<double, n> {
+  public:
+    typedef std::array<double, n> M_t;
+    typedef std::array<double, n> F_t;
+
+    torus_t() {
+      this->fill(0);
+    }
+
+    inline torus_t<n> operator*(v_t a) const {
+      torus_t<n> x;
+      for (q_t i = 0; i < n; i++) {
+        x[i] = a * (*this)[i];
+      }
+
+      return x;
+    }
+
+    inline torus_t<n> operator*(double a) const {
+      torus_t<n> x;
+      for (q_t i = 0; i < n; i++) {
+        x[i] = a * (*this)[i];
+      }
+
+      return x;
+    }
+
+    inline torus_t<n>& operator+=(const torus_t<n>& x) {
+      for (q_t i = 0; i < n; i++) {
+        (*this)[i] += x[i];
+      }
+    }
+
+    inline torus_t<n>& operator-=(const torus_t<n>& x) {
+      for (q_t i = 0; i < n; i++) {
+        (*this)[i] -= x[i];
+      }
+    }
+};
+
+template <q_t n>
+double norm_squared(const torus_t<n>& x) {
+  double tmp = 0;
+  for (const double& xi : x) {
+    tmp += pow(xi, 2);
+  }
+  return tmp;
+}
+
+void write_magnetization(const torus_t<n>& x, FILE *outfile) {
+  for (const double& xi : x) {
+    float tmp_xi = (float)xi;
+    fwrite(&tmp_xi, sizeof(float), 1, outfile);
+  }
+}
+
diff --git a/lib/vector.h b/lib/vector.h
index beee1a7..2f4077a 100644
--- a/lib/vector.h
+++ b/lib/vector.h
@@ -109,7 +109,7 @@ void write_magnetization(vector_t <q, double> M, FILE *outfile) {
 }
 
 template <q_t q, class T>
-T dot(vector_t <q, T> v1, vector_t <q, T> v2) {
+T dot(const vector_t <q, T>& v1, const vector_t <q, T>& v2) {
   T prod = 0;
 
   for (q_t i = 0; i < q; i++) {
@@ -120,7 +120,7 @@ T dot(vector_t <q, T> v1, vector_t <q, T> v2) {
 }
 
 template <q_t q, class T>
-double H_vector(vector_t <q, T> v1, T *H) {
+double H_vector(const vector_t <q, T>& v1, T *H) {
   vector_t <q, T> H_vec(H);
   return (double)(dot <q, T> (v1, H_vec));
 }