Use world iterator in stats

evo/Stats.h

@@ -0,0 +1,111 @@
+//  This file is part of Empirical, https://github.com/devosoft/Empirical/
+//  Copyright (C) Michigan State University, 2016.
+//  Released under the MIT Software license; see doc/LICENSE
+
+//  This file contains functions for calculating various statistics about
+//  a population.
+//
+
+#ifndef EMP_EVO_STATS_H
+#define EMP_EVO_STATS_H
+
+#include <type_traits>
+#include <map>
+#include <cmath>
+#include <vector>
+#include <set>
+#include "../tools/vector.h"
+#include "World.h"
+
+namespace emp{
+namespace evo{
+
+  //Calculates Shannon Entropy of the members of the container passed
+  template <typename C, class = typename C::value_type >
+  double ShannonDiversity(C elements) {
+
+    //Count number of each value present
+    std::map<typename C::value_type, int> counts;
+    for (auto element : elements) {
+      if (counts.find(element) != counts.end()) {
+	       counts[element]++;
+      } else {
+	       counts[element] = 1;
+      }
+    }
+
+    //Shannon entropy calculation
+    double result = 0;
+    for (auto element : counts) {
+      double p = double(element.second)/elements.size();
+      result +=  p * log2(p);
+    }
+
+    return -1 * result;
+  }
+
+  //Calculates Shannon Entropy of the members of a world
+  template <typename ORG, typename... MANAGERS>
+  double ShannonDiversity(emp::evo::World<ORG, MANAGERS...> & elements) {
+
+    //Count number of each value present
+    std::map<ORG, int> counts;
+    for (auto element : elements) {
+      if (counts.find(element) != counts.end()) {
+        counts[element]++;
+      } else {
+        counts[element] = 1;
+      }
+
+    }
+
+    //Shannon entropy calculation
+    double result = 0;
+    for (auto element : counts) {
+      double p = double(element.second)/elements.GetSize();
+      result +=  p * log2(p);
+    }
+
+    return -1 * result;
+  }
+
+  //Calculates number of unique elements in the container passed
+  template <typename C>
+  int Richness(C elements) {
+    //Converting to a set will remove duplicates leaving only unique values
+    std::set<typename C::value_type> unique_elements(elements.begin(),
+						     elements.end());
+    return unique_elements.size();
+  }
+
+  template <typename ORG, typename C, class = typename C::value_type >
+  double MaxFitness(std::function<double(ORG * org)> fit_fun, C orgs){
+    double fittest = fit_fun(&orgs[0]);
+    for (auto org : orgs){
+      double fitness = fit_fun(&org);
+      if (fitness > fittest){
+        fittest = fitness;
+      }
+    }
+    return fittest;
+  }
+
+  template <typename ORG, typename... MANAGERS>
+  double MaxFitness(std::function<double(ORG * org)> fit_fun, World<ORG, MANAGERS...> & orgs){
+    double fittest = fit_fun(&(*(orgs.begin())));
+    for (auto org : orgs){
+      double fitness = fit_fun(&org);
+      if (fitness > fittest){
+        fittest = fitness;
+      }
+    }
+    return fittest;
+  }
+
+}
+}
+
+#endif
+
+//Base class outputs most recent
+//Write derived class