Structure change to make it easier for users to clone and use the repository.

survivor/README.md

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+# Selection functions

survivor/Survivor.py

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+import random
+
+# Import all survivor decorators
+from decorators import *
+
+
+def fill_in_best(ga):
+    """Fills in the next population with the best chromosomes from the last population"""
+
+    needed_amount = len(ga.population) - len(ga.population.next_population)
+    ga.population.append_children(ga.population[:needed_amount])
+
+
+def fill_in_random(ga):
+    """Fills in the next population with random chromosomes from the last population"""
+
+    needed_amount = len(ga.population) - len(ga.population.next_population)
+    ga.population.append_children(random.sample(ga.population, needed_amount))
+
+
+def fill_in_parents_then_random(ga):
+    """Fills in the next population with all parents followed by random chromosomes from the last population"""
+
+    # Remove dupes from the mating pool
+    mating_pool = set(ga.population.mating_pool)
+
+    needed_amount = len(ga.population) - len(ga.population.next_population)
+    parent_amount = min(needed_amount, len(mating_pool))
+    random_amount = needed_amount - parent_amount
+
+    # Only parents are used.
+    if random_amount == 0:
+        ga.population.append_children(
+            chromosome
+            for i, chromosome
+            in enumerate(mating_pool)
+            if i < parent_amount
+        )
+
+    # Parents need to be removed from the random sample to avoid dupes.
+    else:
+        ga.population.append_children(mating_pool)
+        ga.population.append_children(
+               random.sample(
+                  set(ga.population) - mating_pool,
+                  random_amount
+              )
+        )