September Morn Update

Task/Evolutionary-algorithm/00META.yaml

@@ -0,0 +1 @@
+--- {}

Task/Evolutionary-algorithm/Elena/evolutionary-algorithm.elena

@@ -1,68 +1,76 @@
-import system'routines.
-import extensions.
+import system'routines;
+import extensions;
+import extensions'text;
 
-const Target = "METHINKS IT IS LIKE A WEASEL".
-const AllowedCharacters = " ABCDEFGHIJKLMNOPQRSTUVWXYZ".
+const string Target = "METHINKS IT IS LIKE A WEASEL";
+const string AllowedCharacters = " ABCDEFGHIJKLMNOPQRSTUVWXYZ";
 
-const C = 100.
-const P = 0.05r.
+const int C = 100;
+const real P = 0.05r;
 
-rnd = randomGenerator.
+rnd = randomGenerator;
 
 randomChar
-    = AllowedCharacters[rnd nextInt(AllowedCharacters length)].
+    = AllowedCharacters[rnd.nextInt(AllowedCharacters.Length)];
 
 extension evoHelper
 {
-    randomString
-        = 0 till:self repeat(:x)( randomChar ); summarize:(String new); literal.
+    randomString()
+        = 0.repeatTill(self).selectBy:(x => randomChar).summarize(new StringWriter());
 
-    fitnessOf:s
-        = self zip:s by(:a:b)( (a == b)iif(1,0) ); summarize(Integer new); int.
+    fitnessOf(s)
+        = self.zipBy(s, (a,b => a==b ? 1 : 0)).summarize(new Integer()).toInt();
 
-    mutate : p
-        = self selectBy(:ch)( (rnd nextReal <= p) iif(randomChar,ch) ); summarize(String new); literal.
+    mutate(p)
+        = self.selectBy:(ch => rnd.nextReal() <= p ? randomChar : ch).summarize(new StringWriter());
 }
 
-class EvoAlgorithm :: Enumerator
+class EvoAlgorithm : Enumerator
 {
-    object theTarget.
-    object theCurrent.
-    object theVariantCount.
+    object theTarget;
+    object theCurrent;
+    object theVariantCount;
 
-    constructor new : s of:count
-    [
-        theTarget := s.
-        theVariantCount := count int.
-    ]
+    constructor new:of(s,count)
+    {
+        theTarget := s;
+        theVariantCount := count.toInt();
+    }
 
-    get = theCurrent.
+    get() = theCurrent;
 
-    next
-    [
-        if ($nil == theCurrent)
-            [ theCurrent := theTarget length; randomString. ^ true ].
+    bool next()
+    {
+        if (nil == theCurrent)
+            { theCurrent := theTarget.Length.randomString(); ^ true };
 
         if (theTarget == theCurrent)
-            [ ^ false ].
+            { ^ false };
 
-        var variants := Array new:theVariantCount; populate(:x)( theCurrent mutate:P ).
+        auto variants := Array.allocate(theVariantCount).populate:(x => theCurrent.mutate:P );
 
-        theCurrent := variants array; sort(:a:b)( a fitnessOf:Target > b fitnessOf:Target ); getAt:0.
+        theCurrent := variants.sort:(a,b => a.fitnessOf:Target > b.fitnessOf:Target ).at:0;
 
-        ^ true.
-    ]
+        ^ true
+    }
+
+    reset()
+    {
+        theCurrent := nil
+    }
+
+    enumerable() => theTarget;
 }
 
-program =
-[
-    var attempt := Integer new.
-    EvoAlgorithm new:Target of:C; forEach(:current)
-    [
+public program()
+{
+    var attempt := new Integer();
+    EvoAlgorithm.new:Target of:C.forEach:(current)
+    {
         console
-            printPaddingLeft(10,"#",attempt append:1);
-            printLine(" ",current," fitness: ",current fitnessOf:Target).
-    ].
+            .printPaddingLeft(10,"#",attempt.append(1))
+            .printLine(" ",current," fitness: ",current.fitnessOf(Target))
+    };
 
-    console readChar.
-].
+    console.readChar()
+}

Task/Evolutionary-algorithm/Perl-6/evolutionary-algorithm.pl6

@@ -4,7 +4,7 @@ constant @alphabet = flat 'A'..'Z',' ';
 constant C = 100;
 
 sub mutate { [~] (rand < mutate_chance ?? @alphabet.pick !! $_ for $^string.comb) }
-sub fitness { [+] $^string.comb Zeq state @ = target.comb }
+sub fitness { [+] $^string.comb Zeq target.comb }
 
 loop (
     my $parent = @alphabet.roll(target.chars).join;

Task/Evolutionary-algorithm/Swift/evolutionary-algorithm.swift

@@ -0,0 +1,55 @@
+func evolve(
+  to target: String,
+  parent: inout String,
+  mutationRate: Int,
+  copies: Int
+) {
+  var parentFitness: Int {
+    return fitness(target: target, sentence: parent)
+  }
+
+  var generation = 0
+
+  while parent != target {
+    generation += 1
+
+    let bestOfGeneration =
+        (0..<copies)
+          .map({_ in mutate(sentence: parent, rate: mutationRate) })
+          .map({ (fitness(target: target, sentence: $0), $0) })
+          .sorted(by: { $0.0 < $1.0 })
+          .first!
+
+    if bestOfGeneration.0 < parentFitness {
+      print("Gen \(generation) produced better fit. \(bestOfGeneration.1) with fitness \(bestOfGeneration.0)")
+      parent = bestOfGeneration.1
+    }
+  }
+}
+
+func fitness(target: String, sentence: String) -> Int {
+  return zip(target, sentence).filter(!=).count
+}
+
+func mutate(sentence: String, rate: Int) -> String {
+  return String(
+    sentence.map({char in
+      if Int.random(in: 1...100) - rate <= 0 {
+        return "ABCDEFGHIJKLMNOPQRSTUVWXYZ ".randomElement()!
+      } else {
+        return char
+      }
+    })
+  )
+}
+
+let target = "METHINKS IT IS LIKE A WEASEL"
+let copies = 100
+let mutationRate = 20
+
+var start = mutate(sentence: target, rate: 100)
+
+print("target: \(target)")
+print("Gen 0: \(start) with fitness \(fitness(target: target, sentence: start))")
+
+evolve(to: target, parent: &start, mutationRate: mutationRate, copies: 100)