Reverted attempt to make things a little more abstract, because it was very slow for some reason.

1 files changed, 91 insertions, 90 deletions

diff --git a/glass.cpp b/glass.cpp
index e0c5e25..f5e9b31 100644
--- a/glass.cpp
+++ b/glass.cpp
@@ -1,7 +1,6 @@
 #include <iostream>
 #include <vector>
 #include <list>
-#include <set>
 #include <eigen3/Eigen/Dense>
 
 #include "pcg-cpp/include/pcg_random.hpp"
@@ -33,26 +32,39 @@ template<unsigned D> class State {
       σ[a] = b;
     }
 
+    State() : σ(Vector<D>::Zero()) {}
+
+    bool isEmpty() const {
+      return σ.squaredNorm() == 0;
+    }
+
+    void remove() {
+      σ = Vector<D>::Zero();
+    }
+
     State<D> apply(const Matrix<D>& m) const {
       return {m * σ};
     }
 };
 
-template <unsigned D> class Vertex;
+template<unsigned D> State<D> randomState(Rng& r) {
+  return State<D>(r.uniform((unsigned)0, D - 1), r.pick({-1, 1}));
+}
+
+template<unsigned D> class HalfEdge;
 
-template<unsigned D> class Particle {
+template<unsigned D> class Vertex {
   public:
-    Vertex<D>& position;
+    Vector<D> position;
     State<D> state;
+    std::vector<HalfEdge<D>> adjacentEdges;
     bool marked;
 
-    Particle(Vertex<D>& p, const State<D>& s) : position(p), state(s) {}
+    bool isEmpty() const {
+      return state.isEmpty();
+    }
 };
 
-template<unsigned D> State<D> randomState(Rng& r) {
-  return State<D>(r.uniform((unsigned)0, D - 1), r.pick({-1, 1}));
-}
-
 template<unsigned D> class HalfEdge {
   public:
     Vertex<D>& neighbor;
@@ -61,22 +73,11 @@ template<unsigned D> class HalfEdge {
     HalfEdge(Vertex<D>& n, const Vector<D>& d) : neighbor(n), Δx(d) {}
 };
 
-template<unsigned D> class Vertex {
-  public:
-    Vector<D> position;
-    std::vector<HalfEdge<D>> adjacentEdges;
-    Particle<D>* occupant;
-
-    bool empty() const {
-      return occupant == NULL;
-    }
-};
-
 template<unsigned D> class System {
   public:
     const unsigned L;
+    unsigned N;
     std::vector<Vertex<D>> vertices;
-    std::set<Particle<D>*> particles;
 
     unsigned vectorToIndex(const Vector<D>& x) const {
       unsigned i = 0;
@@ -94,15 +95,10 @@ template<unsigned D> class System {
       return x;
     }
 
-    unsigned N() const {
-      return particles.size();
-    }
-
-    System(unsigned L) : L(L), vertices(iPow(L, D)) {
+    System(unsigned L) : L(L), N(0), vertices(iPow(L, D)) {
       for (unsigned i = 0; i < iPow(L, D); i++) {
         vertices[i].position = indexToVector(i);
         vertices[i].adjacentEdges.reserve(2 * D);
-        vertices[i].occupant = NULL;
       }
 
       for (unsigned d = 0; d < D; d++) {
@@ -116,17 +112,21 @@ template<unsigned D> class System {
       }
     }
 
-    std::list<Particle<D>*> overlaps(const Particle<D>& p, bool excludeSelf = false) const {
-      std::list<Particle<D>*> o;
+    std::list<std::reference_wrapper<Vertex<D>>> overlaps(Vertex<D>& v, const State<D>& s, bool excludeSelf = false) {
+      std::list<std::reference_wrapper<Vertex<D>>> o;
+
+      if (s.isEmpty()) {
+        return o;
+      }
 
-      if (!p.position.empty() && !excludeSelf) {
-        o.push_back(p.position.occupant);
+      if (!v.isEmpty() && !excludeSelf) {
+        o.push_back(v);
       }
 
-      for (const HalfEdge<D>& e : p.position.adjacentEdges) {
-        if (!e.neighbor.empty()) {
-          if (p.state.σ.dot(e.Δx) == 1 || e.neighbor.occupant->state.σ.dot(e.Δx) == -1) {
-            o.push_back(e.neighbor.occupant);
+      for (const HalfEdge<D>& e : v.adjacentEdges) {
+        if (!e.neighbor.isEmpty()) {
+          if (s.σ.dot(e.Δx) == 1 || e.neighbor.state.σ.dot(e.Δx) == -1) {
+            o.push_back(e.neighbor);
           } 
         }
       }
@@ -134,61 +134,65 @@ template<unsigned D> class System {
       return o;
     }
 
-    bool insert(const Particle<D>& p) {
-      if (overlaps(p).empty()) {
-        Particle<D>* pN = new Particle<D>(p);
-        particles.insert(pN);
-        p.position.occupant = pN;
+    bool tryInsertion(Vertex<D>& v, const State<D>& s) {
+      if (overlaps(v, s).empty()) {
+        v.state = s;
+        N++;
         return true;
       } else {
         return false;
       }
     }
 
-    void remove(Particle<D>* p) {
-      p->position.occupant = NULL;
-      particles.erase(p);
-      delete p;
+    bool tryDeletion(Vertex<D>& v) {
+      if (v.isEmpty()) {
+        return false;
+      } else {
+        v.state.remove();
+        N--;
+        return true;
+      }
     }
 
-    /*
-    bool randomMove(Rng& r) {
-      Particle<D>& p = *(r.pick(particles));
-      Particle<D> pN = p;
-
-      if (0.2 < r.uniform(0.0, 1.0)) {
-        pN.position = r.pick(p.position.adjacentEdges).neighbor;
+    bool tryRandomMove(Rng& r) {
+      Vertex<D>& v = r.pick(vertices);
+      State<D> oldState = v.state;
+      if (!tryDeletion(v)) {
+        return false;
       }
-      pN.state = randomState<D>(r);
 
-      if (overlaps(pN, true).empty()) {
-        remove(&p);
-        insert(pN);
-        return true;
+      if (0.2 > r.uniform(0.0, 1.0)) {
+        if (tryInsertion(v, randomState<D>(r))) {
+          return true;
+        }
       } else {
-        return false;
+        if (tryInsertion(r.pick(v.adjacentEdges).neighbor, randomState<D>(r))) {
+          return true;
+        }
       }
+      v.state = oldState;
+      N++;
+      return false;
     }
-    */
 
-    bool swap(Particle<D>& p1, Particle<D>& p2) {
-      std::swap(p1.state, p2.state);
-      if (overlaps(p1, true).empty() && overlaps(p2, true).empty()) {
+    bool trySwap(Vertex<D>& v1, Vertex<D>& v2) {
+      if (overlaps(v1, v2.state, true).size() == 0 && overlaps(v2, v1.state, true).size() == 0) {
+        std::swap(v1.state, v2.state);
         return true;
       } else {
-        std::swap(p1.state, p2.state);
         return false;
       }
     }
 
-    bool randomSwap(Rng& r) {
-      return swap(*r.pick(particles), *r.pick(particles));
+    bool tryRandomSwap(Rng& r) {
+      Vertex<D>& v1 = r.pick(vertices);
+      Vertex<D>& v2 = r.pick(vertices);
+
+      return trySwap(v1, v2);
     }
 
     void setGroundState() {
-      for (Particle<D>* p : particles) {
-        remove(p);
-      }
+      N = 0;
 
       for (Vertex<D>& v : vertices) {
         unsigned a = 0;
@@ -197,21 +201,21 @@ template<unsigned D> class System {
         }
         a %= 2 * D + 1;
 
-        if (a > 0) {
-          if (a <= D) {
-            State<D> s(a - 1, -1);
-            insert(Particle<D>(v, s));
-          } else if (D < a) {
-            State<D> s(2 * D - a, 1);
-            insert(Particle<D>(v, s));
-          }
+        v.state.σ = Vector<D>::Zero();
+
+        if (0 < a && a <= D) {
+          v.state.σ(a - 1) = -1;
+          N++;
+        } else if (D < a) {
+          v.state.σ(2 * D - a) = 1;
+          N++;
         }
       }
     }
 
     bool compatible() {
-      for (Particle<D>* p : particles) {
-        if (!overlaps(*p, true).empty()) {
+      for (Vertex<D>& v : vertices) {
+        if (overlaps(v, v.state, true).size() > 0) {
           return false;
         }
       }
@@ -220,7 +224,7 @@ template<unsigned D> class System {
     }
 
     double density() const {
-      return N() / pow(L, D);
+      return N / pow(L, D);
     }
 
     unsigned maxOccupation() const {
@@ -231,40 +235,40 @@ template<unsigned D> class System {
     void sweepGrandCanonical(double z, Rng& r) {
       for (unsigned i = 0; i < iPow(L, D); i++) {
         if (0.5 < r.uniform(0.0, 1.0)) {
-          double pIns = maxOccupation() * z / (N() + 1);
+          double pIns = maxOccupation() * z / (N + 1);
 
           if (pIns > r.uniform(0.0, 1.0)) {
             while (true) {
               Vertex<D>& v = r.pick(vertices);
-              if (v.empty()) {
-                insert(Particle<D>(v, randomState<D>(r)));
+              if (v.isEmpty()) {
+                tryInsertion(v, randomState<D>(r));
                 break;
               }
             }
           }
         } else {
 
-          double pDel = N() / (z * maxOccupation());
+          double pDel = N / (z * maxOccupation());
 
           if (pDel > r.uniform(0.0, 1.0)) {
-            remove(r.pick(particles));
+            tryDeletion(r.pick(vertices));
           }
         }
 
-//        randomMove(r);
-        randomSwap(r);
+        tryRandomMove(r);
+        tryRandomSwap(r);
       }
     }
 
     void sweepLocal(double z, Rng& r) {
       for (unsigned i = 0; i < iPow(L, D); i++) {
-//        randomMove(r);
+        tryRandomMove(r);
       }
     }
 
     void sweepSwap(double z, Rng& r) {
       for (unsigned i = 0; i < iPow(L, D); i++) {
-        randomSwap(r);
+        tryRandomSwap(r);
       }
     }
 
@@ -311,9 +315,6 @@ int main() {
 
   for (unsigned N = Nmin; N <= Nmax; N *= 10) {
     s.setGroundState();
-    if (!s.compatible()) {
-      return 1;
-    }
     for (double T = Tmin; T < Tmax; T *= 1 + δT) {
       double z = exp(1 / T);