Added ability to edit weights and bias values

Author: Guled

Example/MLKit/GameScene.swift

@@ -303,30 +303,32 @@ class GameScene: SKScene, SKPhysicsContactDelegate {
         self.generationLabel.text = "Gen: \(self.generationCounter)"
         print("--------------------------- \n")
 
-        /* DEBUGGING
-        if (currentBird?.fitness)! >= Float(7.0) {
-            print("-----BEST BIRD FOUND------")
-
-            currentBird?.brain?.inputLayer.printLayer(layer: (currentBird?.brain?.inputLayer)!)
-            currentBird?.brain?.hiddenLayer.printLayer(listOfHiddenLayers: (currentBird?.brain?.listOfHiddenLayers)!)
-            currentBird?.brain?.outputLayer.printLayer(layer: (currentBird?.brain?.outputLayer)!)
-
-        }
-        */
-
         // Go to next flappy bird
         currentFlappy += 1
 
         // Filter out the worst birds after gen 6 (can be adjusted)
+
+        if let bird = currentBird {
+            if bird.fitness >= 9.0 {
+                print("FOUND RARE BIRD")
+                print(bird.brain?.layers[0].weights)
+                print(bird.brain?.layers[1].weights)
+                print(bird.brain?.layers[0].bias)
+                print(bird.brain?.layers[1].bias)
+            }
+        }
+
         if generationCounter >= 3 {
 
             // Experiment: Keep some of the last best birds and put them back into the population
             lastBestGen = (flappyBirdGenerationContainer?.filter({$0.fitness >= 7.0}))!
         }
 
-        if (currentBird?.fitness)! > maxFitness {
-            maxFitness = (currentBird?.fitness)!
-            maxBird = currentBird
+        if let bird = currentBird {
+            if bird.fitness > maxFitness {
+                maxFitness = bird.fitness
+                maxBird = bird
+            }
         }
 
         // If we have hit the 20th bird, we need to move on to the next generation
@@ -381,18 +383,15 @@ class GameScene: SKScene, SKPhysicsContactDelegate {
 
             // Set the current bird
             if (flappyBirdGenerationContainer?.count)! > currentFlappy {
-                print("OK!")
                 currentBird = flappyBirdGenerationContainer?[currentFlappy]
             } else {
-                print("NOPE!!!!")
                 currentBird = maxBird
             }
 
         } else {
 
             // Set the current bird
             if (flappyBirdGenerationContainer?.count)! > currentFlappy {
-                print("SUPER OK")
                 currentBird = flappyBirdGenerationContainer?[currentFlappy]
             }
 
@@ -466,14 +465,6 @@ class GameScene: SKScene, SKPhysicsContactDelegate {
 
             let normalizedPosToGap = (posToGap - (-439))/(279 - (-439))
 
-            /*
-            print("======================== \n")
-            print(" DIST: \((finalDistanceOfNextPipe))")
-            print("PIPE POSITION: \(finalPosToGap)")
-            print("Bird POS Y: \(birdPos)")
-            print("======================== \n")
-            */
-
             // Decision AI makes
             let input = Matrix<Float>(rows: 4, columns: 1, elements: [Float(normalizedDistanceOfNextPipe), Float(normalizedPosToGap), Float(birdYPos), Float(normalizedDistanceFromBottomPipe)])
             let decision = currentBird?.brain?.feedforward(input: input)

MLKit/Classes/ANN/Layer.swift

@@ -55,6 +55,42 @@ open class Layer {
     }
 
 
+    /**
+     Manipulate the weights values of a particular Layer object.
+     
+     - parameter newWeights: Weights as a matrix. Shape (rows and columns) must be equivalent to the weights of the Layer object being manipulated.
+
+    */
+    public func editWeights(newWeights:Matrix<Float>) throws{
+
+        if let currentWeights = self.weights {
+            if newWeights.rows != currentWeights.rows && newWeights.columns != currentWeights.columns {
+                throw MachineLearningError.invalidInput
+            }
+        }
+
+        self.weights = newWeights
+    }
+
+
+    /**
+     Manipulate the bias values of a particular Layer object.
+
+     - parameter newBias: Bias as a matrix. Shape (rows and columns) must be equivalent to the bias of the Layer object being manipulated.
+
+     */
+    public func editBias(newBias:Matrix<Float>) throws{
+
+        if let currentBias = self.bias {
+            if newBias.rows != currentBias.rows && newBias.columns != currentBias.columns {
+                throw MachineLearningError.invalidInput
+            }
+        }
+
+        self.bias = newBias
+    }
+
+
     /**
      The forward method passes input into the layers neurons and produces an output matrix. The method saves the input into the Layer objects 'input' atrribute. The method also saves the activation and net value of each neuron into the 'activationValues' and 'zValues' attributes.