Merge branch 'Combination' into 'master'

Combination

MAIDAY

See merge request !4

src/ibea/combination.cpp

 #include "population.h"
 #include "combination.h"
+#include <utility>
+#include <cstdlib>
+#include "../coco/coco.h"
 
-Population SBX20(Population pop){
+  std::pair <double,double> simple_combination(double parent1,double parent2, const double eta, coco_random_state_t *random_generator){
+  double child1;
+  double child2;
+  double u = coco_random_uniform(random_generator);
+  double beta;
+  std::pair <double,double> result;
+  if (u <= 0.5){
+    beta = pow(2*u,1/(1+eta));
+  }
+  else {
+	beta = pow(1/(2*(1-u)),1/(1+eta));
+   }
+  child1 = 0.5*((1+beta)*parent1 + (1-beta)*parent2);
+  child2 = 0.5*((1+beta)*parent1 + (1-beta)*parent2);
+  result= std::make_pair(child1,child2);
+  return result;
+}
+
+/* Recombinaison prédéfini */
+void combine(Population new_pop, Population & pop, coco_random_state_t *random_generator){
+  double eta=20;
+  double u;
+  double size = new_pop.getSize();
+  double dimension = new_pop.getDim();
+  std::pair <double,double> childs;
 
-  return pop;
+  u = coco_random_uniform(random_generator);
+  for (int i; i<floor(size/2); i++){
+    for (int j; j<floor(dimension/2); j++){
+      if (u <= 1){
+        childs = simple_combination(new_pop.getIndiv(i,j), new_pop.getIndiv(size-i-1,dimension-j-1), eta, random_generator);
+	      pop.setIndiv(i,j,childs.first);
+        pop.setIndiv(size-i-1,dimension-j-1,childs.second);
+      }
+    }
+  }
 }

src/ibea/combination.h

 #ifndef COMBINATION_H
 #define COMBINATION_H
-
-Population SBX20(Population pop);
-
+#include "../coco/coco.h"
+#include "population.h"
+double simple_combination(double parent, const double eta, coco_random_state_t *random_generator);
+void combinate(Population population, Population & pop, coco_random_state_t *random_generator);
 #endif
+