Merge pull request #9027 from KonduitAI/master

Development updates [WIP]

python4j/python4j-core/src/main/java/org/nd4j/python4j/PythonTypes.java

@@ -258,7 +258,7 @@ public class PythonTypes {
                     return ret;
                 }else if (javaObject instanceof byte[]){
                     byte[] arr = (byte[]) javaObject;
-                    for (int x : arr) ret.add(x);
+                    for (int x : arr) ret.add(x & 0xff);
                     return ret;
                 } else if (javaObject instanceof long[]) {
                     long[] arr = (long[]) javaObject;

python4j/python4j-core/src/test/java/PythonPrimitiveTypesTest.java

@@ -81,16 +81,31 @@ public class PythonPrimitiveTypesTest {
     }
     @Test
     public void testBytes() {
+        byte[] bytes = new byte[256];
+        for (int i = 0; i < 256; i++) {
+            bytes[i] = (byte) i;
+        }
+        List<PythonVariable> inputs = new ArrayList<>();
+        inputs.add(new PythonVariable<>("b1", PythonTypes.BYTES, bytes));
+        List<PythonVariable> outputs = new ArrayList<>();
+        outputs.add(new PythonVariable<>("b2", PythonTypes.BYTES));
+        String code = "b2=b1";
+        PythonExecutioner.exec(code, inputs, outputs);
+        Assert.assertArrayEquals(bytes, (byte[]) outputs.get(0).getValue());
+    }
+
+    @Test
+    public void testBytes2() {
         byte[] bytes = new byte[]{97, 98, 99};
         List<PythonVariable> inputs = new ArrayList<>();
-        inputs.add(new PythonVariable<>("buff", PythonTypes.BYTES, bytes));
+        inputs.add(new PythonVariable<>("b1", PythonTypes.BYTES, bytes));
         List<PythonVariable> outputs = new ArrayList<>();
         outputs.add(new PythonVariable<>("s1", PythonTypes.STR));
-        outputs.add(new PythonVariable<>("buff2", PythonTypes.BYTES));
+        outputs.add(new PythonVariable<>("b2", PythonTypes.BYTES));
-        String code = "s1 = ''.join(chr(c) for c in buff)\nbuff2=b'def'";
+        String code = "s1 = ''.join(chr(c) for c in b1)\nb2=b'def'";
         PythonExecutioner.exec(code, inputs, outputs);
         Assert.assertEquals("abc", outputs.get(0).getValue());
-        Assert.assertArrayEquals(new byte[]{100, 101, 102}, (byte[])outputs.get(1).getValue());
+        Assert.assertArrayEquals(new byte[]{100, 101, 102}, (byte[]) outputs.get(1).getValue());
     }
 
 }

rl4j/rl4j-core/src/main/java/org/deeplearning4j/rl4j/agent/update/DQNNeuralNetUpdateRule.java

@@ -16,6 +16,8 @@
 package org.deeplearning4j.rl4j.agent.update;
 
 import lombok.Getter;
+import org.deeplearning4j.rl4j.agent.update.neuralnetupdater.INeuralNetUpdater;
+import org.deeplearning4j.rl4j.agent.update.neuralnetupdater.NeuralNetUpdater;
 import org.deeplearning4j.rl4j.learning.sync.Transition;
 import org.deeplearning4j.rl4j.learning.sync.qlearning.discrete.TDTargetAlgorithm.DoubleDQN;
 import org.deeplearning4j.rl4j.learning.sync.qlearning.discrete.TDTargetAlgorithm.ITDTargetAlgorithm;
@@ -29,30 +31,26 @@ import java.util.List;
 // and network update to sub components.
 public class DQNNeuralNetUpdateRule implements IUpdateRule<Transition<Integer>> {
 
-    private final IDQN qNetwork;
     private final IDQN targetQNetwork;
-    private final int targetUpdateFrequency;
+    private final INeuralNetUpdater updater;
 
     private final ITDTargetAlgorithm<Integer> tdTargetAlgorithm;
 
     @Getter
     private int updateCount = 0;
 
-    public DQNNeuralNetUpdateRule(IDQN qNetwork, int targetUpdateFrequency, boolean isDoubleDQN, double gamma, double errorClamp) {
+    public DQNNeuralNetUpdateRule(IDQN<IDQN> qNetwork, int targetUpdateFrequency, boolean isDoubleDQN, double gamma, double errorClamp) {
-        this.qNetwork = qNetwork;
         this.targetQNetwork = qNetwork.clone();
-        this.targetUpdateFrequency = targetUpdateFrequency;
         tdTargetAlgorithm = isDoubleDQN
                 ? new DoubleDQN(qNetwork, targetQNetwork, gamma, errorClamp)
                 : new StandardDQN(qNetwork, targetQNetwork, gamma, errorClamp);
+        updater = new NeuralNetUpdater(qNetwork, targetQNetwork, targetUpdateFrequency);
+
     }
 
     @Override
     public void update(List<Transition<Integer>> trainingBatch) {
-        DataSet targets = tdTargetAlgorithm.computeTDTargets(trainingBatch);
+        DataSet targets = tdTargetAlgorithm.compute(trainingBatch);
-        qNetwork.fit(targets.getFeatures(), targets.getLabels());
+        updater.update(targets);
-        if(++updateCount % targetUpdateFrequency == 0) {
-            targetQNetwork.copy(qNetwork);
-        }
     }
 }

rl4j/rl4j-core/src/main/java/org/deeplearning4j/rl4j/agent/update/neuralnetupdater/INeuralNetUpdater.java

@@ -0,0 +1,30 @@
+/*******************************************************************************
+ * Copyright (c) 2020 Konduit K.K.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Apache License, Version 2.0 which is available at
+ * https://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ ******************************************************************************/
+package org.deeplearning4j.rl4j.agent.update.neuralnetupdater;
+
+import org.nd4j.linalg.dataset.api.DataSet;
+
+/**
+ * The role of INeuralNetUpdater implementations is to update a {@link org.deeplearning4j.rl4j.network.NeuralNet NeuralNet}
+ * from a {@link DataSet}.<p />
+ */
+public interface INeuralNetUpdater {
+    /**
+     * Update a {@link org.deeplearning4j.rl4j.network.NeuralNet NeuralNet}.
+     * @param featuresLabels A Dataset that will be used to update the network.
+     */
+    void update(DataSet featuresLabels);
+}

rl4j/rl4j-core/src/main/java/org/deeplearning4j/rl4j/agent/update/neuralnetupdater/NeuralNetUpdater.java

@@ -0,0 +1,62 @@
+/*******************************************************************************
+ * Copyright (c) 2020 Konduit K.K.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Apache License, Version 2.0 which is available at
+ * https://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ ******************************************************************************/
+package org.deeplearning4j.rl4j.agent.update.neuralnetupdater;
+
+import org.deeplearning4j.rl4j.network.ITrainableNeuralNet;
+import org.nd4j.linalg.dataset.api.DataSet;
+
+/**
+ * A {@link INeuralNetUpdater} that updates a neural network and sync a target network at defined intervals
+ */
+public class NeuralNetUpdater implements INeuralNetUpdater {
+
+    private final ITrainableNeuralNet current;
+    private final ITrainableNeuralNet target;
+
+    private int updateCount = 0;
+    private final int targetUpdateFrequency;
+
+    /**
+     * @param current The current {@link ITrainableNeuralNet network}
+     * @param target The target {@link ITrainableNeuralNet network}
+     * @param targetUpdateFrequency Will synchronize the target network at every <i>targetUpdateFrequency</i> updates
+     */
+    public NeuralNetUpdater(ITrainableNeuralNet current,
+                            ITrainableNeuralNet target,
+                            int targetUpdateFrequency) {
+        this.current = current;
+        this.target = target;
+
+        this.targetUpdateFrequency = targetUpdateFrequency;
+    }
+
+    /**
+     * Update the current network
+     * @param featuresLabels A Dataset that will be used to update the network.
+     */
+    @Override
+    public void update(DataSet featuresLabels) {
+        current.fit(featuresLabels);
+        syncTargetNetwork();
+    }
+
+    private void syncTargetNetwork() {
+        if(++updateCount % targetUpdateFrequency == 0) {
+            target.copy(current);
+        }
+    }
+
+}

rl4j/rl4j-core/src/main/java/org/deeplearning4j/rl4j/learning/async/AsyncThread.java

@@ -23,16 +23,19 @@ import lombok.Setter;
 import lombok.Value;
 import lombok.extern.slf4j.Slf4j;
 import org.deeplearning4j.gym.StepReply;
-import org.deeplearning4j.rl4j.learning.*;
+import org.deeplearning4j.rl4j.learning.HistoryProcessor;
+import org.deeplearning4j.rl4j.learning.IEpochTrainer;
+import org.deeplearning4j.rl4j.learning.IHistoryProcessor;
+import org.deeplearning4j.rl4j.learning.Learning;
 import org.deeplearning4j.rl4j.learning.configuration.IAsyncLearningConfiguration;
 import org.deeplearning4j.rl4j.learning.listener.TrainingListener;
 import org.deeplearning4j.rl4j.learning.listener.TrainingListenerList;
 import org.deeplearning4j.rl4j.mdp.MDP;
 import org.deeplearning4j.rl4j.network.NeuralNet;
-import org.deeplearning4j.rl4j.space.Encodable;
 import org.deeplearning4j.rl4j.observation.Observation;
 import org.deeplearning4j.rl4j.policy.IPolicy;
 import org.deeplearning4j.rl4j.space.ActionSpace;
+import org.deeplearning4j.rl4j.space.Encodable;
 import org.deeplearning4j.rl4j.util.IDataManager;
 import org.deeplearning4j.rl4j.util.LegacyMDPWrapper;
 import org.nd4j.linalg.factory.Nd4j;

rl4j/rl4j-core/src/main/java/org/deeplearning4j/rl4j/learning/async/IAsyncGlobal.java

@@ -18,11 +18,9 @@
 package org.deeplearning4j.rl4j.learning.async;
 
 import org.deeplearning4j.nn.gradient.Gradient;
-import org.deeplearning4j.rl4j.network.NeuralNet;
+import org.deeplearning4j.rl4j.network.ITrainableNeuralNet;
 
-import java.util.concurrent.atomic.AtomicInteger;
+public interface IAsyncGlobal<NN extends ITrainableNeuralNet> {
-
-public interface IAsyncGlobal<NN extends NeuralNet> {
 
     boolean isTrainingComplete();
 

rl4j/rl4j-core/src/main/java/org/deeplearning4j/rl4j/learning/sync/qlearning/discrete/TDTargetAlgorithm/BaseTDTargetAlgorithm.java

@@ -80,7 +80,7 @@ public abstract class BaseTDTargetAlgorithm implements ITDTargetAlgorithm<Intege
     protected abstract double computeTarget(int batchIdx, double reward, boolean isTerminal);
 
     @Override
-    public DataSet computeTDTargets(List<Transition<Integer>> transitions) {
+    public DataSet compute(List<Transition<Integer>> transitions) {
 
         int size = transitions.size();
 

rl4j/rl4j-core/src/main/java/org/deeplearning4j/rl4j/learning/sync/qlearning/discrete/TDTargetAlgorithm/ITDTargetAlgorithm.java

@@ -34,5 +34,5 @@ public interface ITDTargetAlgorithm<A> {
      * @param transitions The transitions from the experience replay
      * @return A DataSet where every element is the observation and the estimated Q-Values for all actions
      */
-    DataSet computeTDTargets(List<Transition<A>> transitions);
+    DataSet compute(List<Transition<A>> transitions);
 }

rl4j/rl4j-core/src/main/java/org/deeplearning4j/rl4j/network/ITrainableNeuralNet.java

@@ -0,0 +1,40 @@
+/*******************************************************************************
+ * Copyright (c) 2020 Konduit K.K.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Apache License, Version 2.0 which is available at
+ * https://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ ******************************************************************************/
+package org.deeplearning4j.rl4j.network;
+
+import org.nd4j.linalg.dataset.api.DataSet;
+
+/**
+ * An interface defining the <i>trainable</i> aspect of a {@link NeuralNet}.
+ */
+public interface ITrainableNeuralNet<NET_TYPE extends ITrainableNeuralNet> {
+    /**
+     * Train the neural net using the supplied <i>feature-labels</i>
+     * @param featuresLabels The feature-labels
+     */
+    void fit(DataSet featuresLabels);
+
+    /**
+     * Changes this instance to be a copy of the <i>from</i> network.
+     * @param from The network that will be the source of the copy.
+     */
+    void copy(NET_TYPE from);
+
+    /**
+     * Creates a clone of the network instance.
+     */
+    NET_TYPE clone();
+}

rl4j/rl4j-core/src/main/java/org/deeplearning4j/rl4j/network/NeuralNet.java

@@ -29,7 +29,7 @@ import java.io.OutputStream;
  * Factorisation between ActorCritic and DQN neural net.
  * Useful for AsyncLearning and Thread code.
  */
-public interface NeuralNet<NN extends NeuralNet> {
+public interface NeuralNet<NN extends NeuralNet> extends IOutputNeuralNet, ITrainableNeuralNet<NN> {
 
     /**
      * Returns the underlying MultiLayerNetwork or ComputationGraph objects.
@@ -52,18 +52,6 @@ public interface NeuralNet<NN extends NeuralNet> {
      */
     INDArray[] outputAll(INDArray batch);
 
-    /**
-     * clone the Neural Net with the same paramaeters
-     * @return the cloned neural net
-     */
-    NN clone();
-
-    /**
-     * copy the parameters from a neural net
-     * @param from where to copy parameters
-     */
-    void copy(NN from);
-
     /**
      * Calculate the gradients from input and label (target) of all outputs
      * @param input input batch

rl4j/rl4j-core/src/main/java/org/deeplearning4j/rl4j/network/ac/ActorCriticCompGraph.java

@@ -18,6 +18,7 @@
 package org.deeplearning4j.rl4j.network.ac;
 
 import lombok.Getter;
+import org.apache.commons.lang3.NotImplementedException;
 import org.deeplearning4j.nn.api.NeuralNetwork;
 import org.deeplearning4j.nn.conf.ComputationGraphConfiguration;
 import org.deeplearning4j.nn.gradient.Gradient;
@@ -25,8 +26,10 @@ import org.deeplearning4j.nn.graph.ComputationGraph;
 import org.deeplearning4j.nn.layers.recurrent.RnnOutputLayer;
 import org.deeplearning4j.nn.workspace.LayerWorkspaceMgr;
 import org.deeplearning4j.optimize.api.TrainingListener;
+import org.deeplearning4j.rl4j.observation.Observation;
 import org.deeplearning4j.util.ModelSerializer;
 import org.nd4j.linalg.api.ndarray.INDArray;
+import org.nd4j.linalg.dataset.api.DataSet;
 
 import java.io.IOException;
 import java.io.OutputStream;
@@ -80,6 +83,11 @@ public class ActorCriticCompGraph implements IActorCritic<ActorCriticCompGraph>
         return nn;
     }
 
+    @Override
+    public void fit(DataSet featuresLabels) {
+        fit(featuresLabels.getFeatures(), new INDArray[] { featuresLabels.getLabels() });
+    }
+
     public void copy(ActorCriticCompGraph from) {
         cg.setParams(from.cg.params());
     }
@@ -137,5 +145,19 @@ public class ActorCriticCompGraph implements IActorCritic<ActorCriticCompGraph>
     public void save(String pathValue, String pathPolicy) throws IOException {
         throw new UnsupportedOperationException("Call save(path)");
     }
+
+    @Override
+    public INDArray output(Observation observation) {
+        // TODO: signature of output() will change to return a class that has named outputs to support network like
+        // this one (output from the value-network and another output for the policy-network
+        throw new NotImplementedException("Not implemented: will be done with AgentLearner async support");
+    }
+
+    @Override
+    public INDArray output(INDArray batch) {
+        // TODO: signature of output() will change to return a class that has named outputs to support network like
+        // this one (output from the value-network and another output for the policy-network
+        throw new NotImplementedException("Not implemented: will be done with AgentLearner async support");
+    }
 }
 

rl4j/rl4j-core/src/main/java/org/deeplearning4j/rl4j/network/ac/ActorCriticSeparate.java

@@ -17,6 +17,7 @@
 package org.deeplearning4j.rl4j.network.ac;
 
 import lombok.Getter;
+import org.apache.commons.lang3.NotImplementedException;
 import org.deeplearning4j.nn.api.NeuralNetwork;
 import org.deeplearning4j.nn.conf.MultiLayerConfiguration;
 import org.deeplearning4j.nn.gradient.Gradient;
@@ -24,8 +25,10 @@ import org.deeplearning4j.nn.layers.recurrent.RnnOutputLayer;
 import org.deeplearning4j.nn.multilayer.MultiLayerNetwork;
 import org.deeplearning4j.nn.workspace.LayerWorkspaceMgr;
 import org.deeplearning4j.optimize.api.TrainingListener;
+import org.deeplearning4j.rl4j.observation.Observation;
 import org.deeplearning4j.util.ModelSerializer;
 import org.nd4j.linalg.api.ndarray.INDArray;
+import org.nd4j.linalg.dataset.api.DataSet;
 
 import java.io.IOException;
 import java.io.OutputStream;
@@ -86,6 +89,13 @@ public class ActorCriticSeparate<NN extends ActorCriticSeparate> implements IAct
         return nn;
     }
 
+    @Override
+    public void fit(DataSet featuresLabels) {
+        // TODO: signature of fit() will change from DataSet to a class that has named labels to support network like
+        // this one (labels for the value-network and another labels for the policy-network
+        throw new NotImplementedException("Not implemented: will be done with AgentLearner async support");
+    }
+
     public void copy(NN from) {
         valueNet.setParams(from.valueNet.params());
         policyNet.setParams(from.policyNet.params());
@@ -164,6 +174,20 @@ public class ActorCriticSeparate<NN extends ActorCriticSeparate> implements IAct
         ModelSerializer.writeModel(valueNet, pathValue, true);
         ModelSerializer.writeModel(policyNet, pathPolicy, true);
     }
+
+    @Override
+    public INDArray output(Observation observation) {
+        // TODO: signature of output() will change to return a class that has named outputs to support network like
+        // this one (output from the value-network and another output for the policy-network
+        throw new NotImplementedException("Not implemented: will be done with AgentLearner async support");
+    }
+
+    @Override
+    public INDArray output(INDArray batch) {
+        // TODO: signature of output() will change to return a class that has named outputs to support network like
+        // this one (output from the value-network and another output for the policy-network
+        throw new NotImplementedException("Not implemented: will be done with AgentLearner async support");
+    }
 }
 
 

rl4j/rl4j-core/src/main/java/org/deeplearning4j/rl4j/network/ac/IActorCritic.java

@@ -16,7 +16,6 @@
 
 package org.deeplearning4j.rl4j.network.ac;
 
-import org.deeplearning4j.nn.gradient.Gradient;
 import org.deeplearning4j.rl4j.network.NeuralNet;
 import org.nd4j.linalg.api.ndarray.INDArray;
 
@@ -33,27 +32,11 @@ import java.io.OutputStream;
  */
 public interface IActorCritic<NN extends IActorCritic> extends NeuralNet<NN> {
 
-    boolean isRecurrent();
-
-    void reset();
-
-    void fit(INDArray input, INDArray[] labels);
-
     //FIRST SHOULD BE VALUE AND SECOND IS SOFTMAX POLICY. DONT MESS THIS UP OR ELSE ASYNC THREAD IS BROKEN (maxQ) !
     INDArray[] outputAll(INDArray batch);
 
-    NN clone();
-
-    void copy(NN from);
-
-    Gradient[] gradient(INDArray input, INDArray[] labels);
-
-    void applyGradient(Gradient[] gradient, int batchSize);
-
     void save(OutputStream streamValue, OutputStream streamPolicy) throws IOException;
 
     void save(String pathValue, String pathPolicy) throws IOException;
 
-    double getLatestScore();
-
 }

rl4j/rl4j-core/src/main/java/org/deeplearning4j/rl4j/network/dqn/DQN.java

@@ -25,6 +25,7 @@ import org.deeplearning4j.optimize.api.TrainingListener;
 import org.deeplearning4j.rl4j.observation.Observation;
 import org.deeplearning4j.util.ModelSerializer;
 import org.nd4j.linalg.api.ndarray.INDArray;
+import org.nd4j.linalg.dataset.api.DataSet;
 
 import java.io.IOException;
 import java.io.OutputStream;
@@ -33,7 +34,7 @@ import java.util.Collection;
 /**
  * @author rubenfiszel (ruben.fiszel@epfl.ch) 7/25/16.
  */
-public class DQN<NN extends DQN> implements IDQN<NN> {
+public class DQN implements IDQN<DQN> {
 
     final protected MultiLayerNetwork mln;
 
@@ -79,16 +80,23 @@ public class DQN<NN extends DQN> implements IDQN<NN> {
         return new INDArray[] {output(batch)};
     }
 
-    public NN clone() {
+    @Override
-        NN nn = (NN)new DQN(mln.clone());
+    public void fit(DataSet featuresLabels) {
-        nn.mln.setListeners(mln.getListeners());
+        fit(featuresLabels.getFeatures(), featuresLabels.getLabels());
-        return nn;
     }
 
-    public void copy(NN from) {
+    @Override
+    public void copy(DQN from) {
         mln.setParams(from.mln.params());
     }
 
+    @Override
+    public DQN clone() {
+        DQN nn = new DQN(mln.clone());
+        nn.mln.setListeners(mln.getListeners());
+        return nn;
+    }
+
     public Gradient[] gradient(INDArray input, INDArray labels) {
         mln.setInput(input);
         mln.setLabels(labels);

rl4j/rl4j-core/src/main/java/org/deeplearning4j/rl4j/network/dqn/IDQN.java

@@ -17,9 +17,7 @@
 package org.deeplearning4j.rl4j.network.dqn;
 
 import org.deeplearning4j.nn.gradient.Gradient;
-import org.deeplearning4j.rl4j.network.IOutputNeuralNet;
 import org.deeplearning4j.rl4j.network.NeuralNet;
-import org.deeplearning4j.rl4j.observation.Observation;
 import org.nd4j.linalg.api.ndarray.INDArray;
 
 /**
@@ -28,27 +26,11 @@ import org.nd4j.linalg.api.ndarray.INDArray;
  * This neural net quantify the value of each action given a state
  *
  */
-public interface IDQN<NN extends IDQN> extends NeuralNet<NN>, IOutputNeuralNet {
+public interface IDQN<NN extends IDQN> extends NeuralNet<NN> {
-
-    boolean isRecurrent();
-
-    void reset();
 
     void fit(INDArray input, INDArray labels);
 
-    void fit(INDArray input, INDArray[] labels);
-	
-    INDArray[] outputAll(INDArray batch);
-
-    NN clone();
-
-    void copy(NN from);
-
     Gradient[] gradient(INDArray input, INDArray label);
 
     Gradient[] gradient(INDArray input, INDArray[] label);
-
-    void applyGradient(Gradient[] gradient, int batchSize);
-
-    double getLatestScore();
 }

rl4j/rl4j-core/src/test/java/org/deeplearning4j/rl4j/agent/update/neuralnetupdater/NeuralNetUpdaterTest.java

@@ -0,0 +1,51 @@
+package org.deeplearning4j.rl4j.agent.update.neuralnetupdater;
+
+import org.deeplearning4j.rl4j.network.ITrainableNeuralNet;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+import org.nd4j.linalg.dataset.api.DataSet;
+
+import static org.mockito.Mockito.*;
+
+@RunWith(MockitoJUnitRunner.class)
+public class NeuralNetUpdaterTest {
+
+    @Mock
+    ITrainableNeuralNet currentMock;
+
+    @Mock
+    ITrainableNeuralNet targetMock;
+
+    @Test
+    public void when_callingUpdate_expect_currentUpdatedAndtargetNotChanged() {
+        // Arrange
+        NeuralNetUpdater sut = new NeuralNetUpdater(currentMock, targetMock, Integer.MAX_VALUE);
+        DataSet featureLabels = new org.nd4j.linalg.dataset.DataSet();
+
+        // Act
+        sut.update(featureLabels);
+
+        // Assert
+        verify(currentMock, times(1)).fit(featureLabels);
+        verify(targetMock, never()).fit(any());
+    }
+
+    @Test
+    public void when_callingUpdate_expect_targetUpdatedFromCurrentAtFrequency() {
+        // Arrange
+        NeuralNetUpdater sut = new NeuralNetUpdater(currentMock, targetMock, 3);
+        DataSet featureLabels = new org.nd4j.linalg.dataset.DataSet();
+
+        // Act
+        sut.update(featureLabels);
+        sut.update(featureLabels);
+        sut.update(featureLabels);
+
+        // Assert
+        verify(currentMock, never()).copy(any());
+        verify(targetMock, times(1)).copy(currentMock);
+    }
+
+}

rl4j/rl4j-core/src/test/java/org/deeplearning4j/rl4j/learning/sync/qlearning/discrete/TDTargetAlgorithm/DoubleDQNTest.java

@@ -50,7 +50,7 @@ public class DoubleDQNTest {
         DoubleDQN sut = new DoubleDQN(qNetworkMock, targetQNetworkMock, 0.5);
 
         // Act
-        DataSet result = sut.computeTDTargets(transitions);
+        DataSet result = sut.compute(transitions);
 
         // Assert
         INDArray evaluatedQValues = result.getLabels();
@@ -74,7 +74,7 @@ public class DoubleDQNTest {
         DoubleDQN sut = new DoubleDQN(qNetworkMock, targetQNetworkMock, 0.5);
 
         // Act
-        DataSet result = sut.computeTDTargets(transitions);
+        DataSet result = sut.compute(transitions);
 
         // Assert
         INDArray evaluatedQValues = result.getLabels();
@@ -102,7 +102,7 @@ public class DoubleDQNTest {
         DoubleDQN sut = new DoubleDQN(qNetworkMock, targetQNetworkMock, 0.5);
 
         // Act
-        DataSet result = sut.computeTDTargets(transitions);
+        DataSet result = sut.compute(transitions);
 
         // Assert
         INDArray evaluatedQValues = result.getLabels();

rl4j/rl4j-core/src/test/java/org/deeplearning4j/rl4j/learning/sync/qlearning/discrete/TDTargetAlgorithm/StandardDQNTest.java

@@ -50,7 +50,7 @@ public class StandardDQNTest {
         StandardDQN sut = new StandardDQN(qNetworkMock, targetQNetworkMock, 0.5);
 
         // Act
-        DataSet result = sut.computeTDTargets(transitions);
+        DataSet result = sut.compute(transitions);
 
         // Assert
         INDArray evaluatedQValues = result.getLabels();
@@ -72,7 +72,7 @@ public class StandardDQNTest {
         StandardDQN sut = new StandardDQN(qNetworkMock, targetQNetworkMock, 0.5);
 
         // Act
-        DataSet result = sut.computeTDTargets(transitions);
+        DataSet result = sut.compute(transitions);
 
         // Assert
         INDArray evaluatedQValues = result.getLabels();
@@ -98,7 +98,7 @@ public class StandardDQNTest {
         StandardDQN sut = new StandardDQN(qNetworkMock, targetQNetworkMock, 0.5);
 
         // Act
-        DataSet result = sut.computeTDTargets(transitions);
+        DataSet result = sut.compute(transitions);
 
         // Assert
         INDArray evaluatedQValues = result.getLabels();

rl4j/rl4j-core/src/test/java/org/deeplearning4j/rl4j/learning/sync/support/MockDQN.java

@@ -2,10 +2,12 @@ package org.deeplearning4j.rl4j.learning.sync.support;
 
 import org.deeplearning4j.nn.api.NeuralNetwork;
 import org.deeplearning4j.nn.gradient.Gradient;
+import org.deeplearning4j.rl4j.network.ITrainableNeuralNet;
 import org.deeplearning4j.rl4j.network.NeuralNet;
 import org.deeplearning4j.rl4j.network.dqn.IDQN;
 import org.deeplearning4j.rl4j.observation.Observation;
 import org.nd4j.linalg.api.ndarray.INDArray;
+import org.nd4j.linalg.dataset.api.DataSet;
 
 import java.io.IOException;
 import java.io.OutputStream;
@@ -66,21 +68,21 @@ public class MockDQN implements IDQN {
         return new INDArray[0];
     }
 
+    @Override
+    public void fit(DataSet featuresLabels) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public void copy(ITrainableNeuralNet from) {
+        throw new UnsupportedOperationException();
+    }
+
     @Override
     public IDQN clone() {
         return null;
     }
 
-    @Override
-    public void copy(NeuralNet from) {
-
-    }
-
-    @Override
-    public void copy(IDQN from) {
-
-    }
-
     @Override
     public Gradient[] gradient(INDArray input, INDArray label) {
         return new Gradient[0];

rl4j/rl4j-core/src/test/java/org/deeplearning4j/rl4j/policy/PolicyTest.java

@@ -36,6 +36,7 @@ import org.deeplearning4j.rl4j.util.LegacyMDPWrapper;
 import org.junit.Test;
 import org.nd4j.linalg.activations.Activation;
 import org.nd4j.linalg.api.ndarray.INDArray;
+import org.nd4j.linalg.dataset.api.DataSet;
 import org.nd4j.linalg.factory.Nd4j;
 import org.nd4j.linalg.lossfunctions.LossFunctions;
 
@@ -88,6 +89,11 @@ public class PolicyTest {
             throw new UnsupportedOperationException();
         }
 
+        @Override
+        public void fit(DataSet featuresLabels) {
+            throw new UnsupportedOperationException();
+        }
+
         @Override
         public void copy(NN from) {
             throw new UnsupportedOperationException();
@@ -127,6 +133,16 @@ public class PolicyTest {
         public void save(String filename) throws IOException {
             throw new UnsupportedOperationException();
         }
+
+        @Override
+        public INDArray output(Observation observation) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public INDArray output(INDArray batch) {
+            throw new UnsupportedOperationException();
+        }
     }
 
     @Test

rl4j/rl4j-core/src/test/java/org/deeplearning4j/rl4j/support/MockDQN.java

@@ -2,11 +2,13 @@ package org.deeplearning4j.rl4j.support;
 
 import org.deeplearning4j.nn.api.NeuralNetwork;
 import org.deeplearning4j.nn.gradient.Gradient;
+import org.deeplearning4j.rl4j.network.ITrainableNeuralNet;
 import org.deeplearning4j.rl4j.network.NeuralNet;
 import org.deeplearning4j.rl4j.network.dqn.IDQN;
 import org.deeplearning4j.rl4j.observation.Observation;
 import org.nd4j.linalg.api.ndarray.INDArray;
 import org.nd4j.common.primitives.Pair;
+import org.nd4j.linalg.dataset.api.DataSet;
 
 import java.io.IOException;
 import java.io.OutputStream;
@@ -63,6 +65,16 @@ public class MockDQN implements IDQN {
         return new INDArray[] { batch.mul(-1.0) };
     }
 
+    @Override
+    public void fit(DataSet featuresLabels) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public void copy(ITrainableNeuralNet from) {
+        throw new UnsupportedOperationException();
+    }
+
     @Override
     public IDQN clone() {
         MockDQN clone = new MockDQN();
@@ -71,16 +83,6 @@ public class MockDQN implements IDQN {
         return clone;
     }
 
-    @Override
-    public void copy(NeuralNet from) {
-
-    }
-
-    @Override
-    public void copy(IDQN from) {
-
-    }
-
     @Override
     public Gradient[] gradient(INDArray input, INDArray label) {
         gradientParams.add(new Pair<INDArray, INDArray>(input, label));

rl4j/rl4j-core/src/test/java/org/deeplearning4j/rl4j/support/MockNeuralNet.java

@@ -2,8 +2,11 @@ package org.deeplearning4j.rl4j.support;
 
 import org.deeplearning4j.nn.api.NeuralNetwork;
 import org.deeplearning4j.nn.gradient.Gradient;
+import org.deeplearning4j.rl4j.network.ITrainableNeuralNet;
 import org.deeplearning4j.rl4j.network.NeuralNet;
+import org.deeplearning4j.rl4j.observation.Observation;
 import org.nd4j.linalg.api.ndarray.INDArray;
+import org.nd4j.linalg.dataset.api.DataSet;
 import org.nd4j.linalg.factory.Nd4j;
 
 import java.io.IOException;
@@ -39,15 +42,20 @@ public class MockNeuralNet implements NeuralNet {
     }
 
     @Override
-    public NeuralNet clone() {
+    public void fit(DataSet featuresLabels) {
-        return this;
+        throw new UnsupportedOperationException();
     }
 
     @Override
-    public void copy(NeuralNet from) {
+    public void copy(ITrainableNeuralNet from) {
         ++copyCallCount;
     }
 
+    @Override
+    public NeuralNet clone() {
+        return this;
+    }
+
     @Override
     public Gradient[] gradient(INDArray input, INDArray[] labels) {
         return new Gradient[0];
@@ -77,4 +85,14 @@ public class MockNeuralNet implements NeuralNet {
     public void save(String filename) throws IOException {
 
     }
+
+    @Override
+    public INDArray output(Observation observation) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public INDArray output(INDArray batch) {
+        throw new UnsupportedOperationException();
+    }
 }