Changeset 966:5e865c5c8a87 in lemon-0.x for src/work/akos

Timestamp:

11/08/04 09:40:37 (20 years ago)

Author:

Akos Ladanyi

Branch:

default

Phase:

public

Convert:

svn:c9d7d8f5-90d6-0310-b91f-818b3a526b0e/lemon/trunk@1351

Message:

Added an init method to the controller, and started writing a second controller.

File:

• src/work/akos/simann.h (modified) (5 diffs)

src/work/akos/simann.h

@@ -1 +1 @@
 #ifndef LEMON_SIMANN_H
 #define LEMON_SIMANN_H
+
+#include <cstdlib>
+#include <cmath>
+#include <sys/time.h>
 
 namespace lemon {
@@ -31 +35 @@
     double getBestCost() { return best_cost; }
     void run() {
+      controller->init();
       while (controller->next()) {
         mutate();
@@ -50 +55 @@
     public:
       SimAnnBase *base;
+      virtual void init() {}
       virtual void acceptEvent() {}
       virtual void improveEvent() {}
@@ -85 +91 @@
   class EntitySkeleton {
   public:
-    // returns the new cost
+    /*! \brief Makes a minor change to the entity.
+     *  \return the new cost
+     */
     double mutate() { return 0.0; }
-    // restores the entity to its previous state i.e. reverts the effects of
-    // the last mutate()
+    /*! \brief Restores the entity to its previous state i.e. reverts the
+     *  effects of the last mutate.
+     */
     void revert() {}
   };
 
+  /*! \brief A simple controller for the simulated annealing class.
+   *  \todo Find a way to set the various parameters.
+   */
   class SimpleController : public SimAnnBase::Controller {
   public:
@@ -118 +130 @@
     }
     bool accept() {
-      return (drand48() <= exp(base->getPrevCost() - base->getCurrCost() / temp));
+      return (drand48() <= exp(base->getPrevCost() - base->getCurrCost() /
+        temp));
+    }
+  };
+
+  /*! \brief A controller with preset running time for the simulated annealing
+   *  class.
+   *  \todo Find a better name.
+   */
+  class AdvancedController : public SimAnnBase::Controller {
+  private:
+    double threshold() { return 0.0; }
+  public:
+    double alpha;
+    double temp;
+    double avg_cost;
+    double start_time, end_time;
+    void init() {
+      timeval tv;
+      gettimeofday(&tv, 0);
+      start_time = tv.tv_sec + double(tv.tv_usec) / 1e6;
+    }
+    void acceptEvent() {
+      avg_cost = alpha * base->getCurrCost() + (1.0 - alpha) * avg_cost;
+    }
+    void improveEvent() {
+    }
+    void rejectEvent() {
+    }
+    bool next() {
+      // abs(avg_cost - base->getBestCost())
+      // ha nagy: cooling factor novelese
+      // ha kicsi: homerseklet novelese
+      // de mennyivel?
+      timeval tv;
+      gettimeofday(&tv, 0);
+      double elapsed_time = tv.tv_sec + double(tv.tv_usec) / 1e6 - start_time;
+      return elapsed_time < end_time;
+    }
+    bool accept() {
+      return (drand48() <= exp(base->getPrevCost() - base->getCurrCost() /
+        temp));
     }
   };