Exemple #1
0
 public static void Update(string epoch, Accuracy acc)
 {
     string[] l = acc.Get();
     try
     {
         Console.SetCursorPosition(0, 0);
         Console.Write(new string(' ', Console.BufferWidth));
         Console.SetCursorPosition(0, 0);
         var time = DateTime.UtcNow - Process.GetCurrentProcess().StartTime.ToUniversalTime();
         epoch += " : " + time + " elapsed";
         Console.Write(epoch);
     }
     catch
     {
         Console.WriteLine(epoch);
     }
     for (int i = 0; i < l.Count(); i++)
     {
         try
         {
             Console.SetCursorPosition(0, i + 1);
             Console.Write(new String(' ', Console.BufferWidth));
             Console.SetCursorPosition(0, i + 1);
             Console.Write(l[i]);
         }
         catch
         {
             Console.WriteLine(l[i]);
         }
     }
 }
Exemple #2
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        public static void RunSimple()
        {
            var mnist      = TestUtils.GetMNIST(); //Get the MNIST dataset, it will download if not found
            var batch_size = 100;                  //Set training batch size
            var train_data = new NDArrayIter(mnist["train_data"], mnist["train_label"], batch_size);
            var val_data   = new NDArrayIter(mnist["test_data"], mnist["test_label"], batch_size);

            // Define simple network with dense layers
            var net = new Sequential();

            net.Add(new Dense(128, ActivationType.Relu));
            net.Add(new Dense(64, ActivationType.Relu));
            net.Add(new Dense(10));

            //Set context, multi-gpu supported
            var gpus = TestUtils.ListGpus();
            var ctx  = gpus.Count > 0 ? gpus.Select(x => Context.Gpu(x)).ToArray() : new[] { Context.Cpu(0) };

            //Initialize the weights
            net.Initialize(new Xavier(magnitude: 2.24f), ctx);

            //Create the trainer with all the network parameters and set the optimizer
            var trainer = new Trainer(net.CollectParams(), new Adam());

            var   epoch  = 10;
            var   metric = new Accuracy(); //Use Accuracy as the evaluation metric.
            var   softmax_cross_entropy_loss = new SoftmaxCrossEntropyLoss();
            float lossVal = 0;             //For loss calculation

            for (var iter = 0; iter < epoch; iter++)
            {
                var tic = DateTime.Now;
                // Reset the train data iterator.
                train_data.Reset();
                lossVal = 0;

                // Loop over the train data iterator.
                while (!train_data.End())
                {
                    var batch = train_data.Next();

                    // Splits train data into multiple slices along batch_axis
                    // and copy each slice into a context.
                    var data = Utils.SplitAndLoad(batch.Data[0], ctx, batch_axis: 0);

                    // Splits train labels into multiple slices along batch_axis
                    // and copy each slice into a context.
                    var label = Utils.SplitAndLoad(batch.Label[0], ctx, batch_axis: 0);

                    var outputs = new NDArrayList();

                    // Inside training scope
                    NDArray loss = null;
                    for (int i = 0; i < data.Length; i++)
                    {
                        using (var ag = Autograd.Record())
                        {
                            var x = data[i];
                            var y = label[i];
                            var z = net.Call(x);
                            // Computes softmax cross entropy loss.
                            loss = softmax_cross_entropy_loss.Call(z, y);
                            outputs.Add(z);
                        }

                        // Backpropagate the error for one iteration.
                        loss.Backward();
                        lossVal += loss.Mean();
                    }

                    // Updates internal evaluation
                    metric.Update(label, outputs.ToArray());

                    // Make one step of parameter update. Trainer needs to know the
                    // batch size of data to normalize the gradient by 1/batch_size.
                    trainer.Step(batch.Data[0].Shape[0]);
                }

                var toc = DateTime.Now;

                // Gets the evaluation result.
                var(name, acc) = metric.Get();

                // Reset evaluation result to initial state.
                metric.Reset();
                Console.Write($"Loss: {lossVal} ");
                Console.WriteLine($"Training acc at epoch {iter}: {name}={(acc * 100).ToString("0.##")}%, Duration: {(toc - tic).TotalSeconds.ToString("0.#")}s");
            }
        }
Exemple #3
0
        public static void RunConv()
        {
            var mnist      = TestUtils.GetMNIST();
            var batch_size = 128;
            var train_data = new NDArrayIter(mnist["train_data"], mnist["train_label"], batch_size, true);
            var val_data   = new NDArrayIter(mnist["test_data"], mnist["test_label"], batch_size);

            var net = new Sequential();

            net.Add(new Conv2D(20, kernel_size: (5, 5), activation: ActivationType.Tanh));
            net.Add(new MaxPool2D(pool_size: (2, 2), strides: (2, 2)));
            net.Add(new Conv2D(50, kernel_size: (5, 5), activation: ActivationType.Tanh));
            net.Add(new MaxPool2D(pool_size: (2, 2), strides: (2, 2)));
            net.Add(new Flatten());
            net.Add(new Dense(500, ActivationType.Tanh));
            net.Add(new Dense(10));

            var gpus = TestUtils.ListGpus();
            var ctx  = gpus.Count > 0 ? gpus.Select(x => Context.Gpu(x)).ToArray() : new[] { Context.Cpu(0) };

            net.Initialize(new Xavier(magnitude: 2.24f), ctx);
            var trainer = new Trainer(net.CollectParams(), new SGD(learning_rate: 0.02f));

            var   epoch  = 10;
            var   metric = new Accuracy();
            var   softmax_cross_entropy_loss = new SoftmaxCELoss();
            float lossVal = 0;

            for (var iter = 0; iter < epoch; iter++)
            {
                var tic = DateTime.Now;
                train_data.Reset();
                lossVal = 0;
                while (!train_data.End())
                {
                    var batch = train_data.Next();
                    var data  = Utils.SplitAndLoad(batch.Data[0], ctx, batch_axis: 0);
                    var label = Utils.SplitAndLoad(batch.Label[0], ctx, batch_axis: 0);

                    var outputs = new NDArrayList();
                    using (var ag = Autograd.Record())
                    {
                        for (var i = 0; i < data.Length; i++)
                        {
                            var x = data[i];
                            var y = label[i];

                            var     z    = net.Call(x);
                            NDArray loss = softmax_cross_entropy_loss.Call(z, y);
                            loss.Backward();
                            lossVal += loss.Mean();
                            outputs.Add(z);
                        }

                        //outputs = Enumerable.Zip(data, label, (x, y) =>
                        //{
                        //    var z = net.Call(x);
                        //    NDArray loss = softmax_cross_entropy_loss.Call(z, y);
                        //    loss.Backward();
                        //    lossVal += loss.Mean();
                        //    return z;
                        //}).ToList();
                    }

                    metric.Update(label, outputs.ToArray());
                    trainer.Step(batch.Data[0].Shape[0]);
                }

                var toc = DateTime.Now;

                var(name, acc) = metric.Get();
                metric.Reset();
                Console.Write($"Loss: {lossVal} ");
                Console.WriteLine($"Training acc at epoch {iter}: {name}={(acc * 100).ToString("0.##")}%, Duration: {(toc - tic).TotalSeconds.ToString("0.#")}s");
            }
        }
        private static void Main()
        {
            const int imageSize = 28;

            int[]       layers       = { 128, 64, 10 };
            const int   batchSize    = 100;
            const int   maxEpoch     = 10;
            const float learningRate = 0.1f;
            const float weightDecay  = 1e-2f;

            var trainIter = new MXDataIter("MNISTIter")
                            .SetParam("image", "./mnist_data/train-images-idx3-ubyte")
                            .SetParam("label", "./mnist_data/train-labels-idx1-ubyte")
                            .SetParam("batch_size", batchSize)
                            .SetParam("flat", 1)
                            .CreateDataIter();
            var valIter = new MXDataIter("MNISTIter")
                          .SetParam("image", "./mnist_data/t10k-images-idx3-ubyte")
                          .SetParam("label", "./mnist_data/t10k-labels-idx1-ubyte")
                          .SetParam("batch_size", batchSize)
                          .SetParam("flat", 1)
                          .CreateDataIter();

            var net = Mlp(layers);

            Context ctx = Context.Cpu();  // Use CPU for training

            var args = new SortedDictionary <string, NDArray>();

            args["X"]     = new NDArray(new Shape(batchSize, imageSize * imageSize), ctx);
            args["label"] = new NDArray(new Shape(batchSize), ctx);
            // Let MXNet infer shapes other parameters such as weights
            net.InferArgsMap(ctx, args, args);

            // Initialize all parameters with uniform distribution U(-0.01, 0.01)
            var initializer = new Uniform(0.01f);

            foreach (var arg in args)
            {
                // arg.first is parameter name, and arg.second is the value
                initializer.Operator(arg.Key, arg.Value);
            }

            // Create sgd optimizer
            var opt = OptimizerRegistry.Find("sgd");

            opt.SetParam("rescale_grad", 1.0 / batchSize)
            .SetParam("lr", learningRate)
            .SetParam("wd", weightDecay);

            // Create executor by binding parameters to the model
            using (var exec = net.SimpleBind(ctx, args))
            {
                var argNames = net.ListArguments();

                // Start training
                var sw = new Stopwatch();
                for (var iter = 0; iter < maxEpoch; ++iter)
                {
                    var samples = 0;
                    trainIter.Reset();

                    sw.Restart();

                    while (trainIter.Next())
                    {
                        samples += batchSize;
                        var dataBatch = trainIter.GetDataBatch();
                        // Set data and label
                        dataBatch.Data.CopyTo(args["X"]);
                        dataBatch.Label.CopyTo(args["label"]);

                        // Compute gradients
                        exec.Forward(true);
                        exec.Backward();
                        // Update parameters
                        for (var i = 0; i < argNames.Count; ++i)
                        {
                            if (argNames[i] == "X" || argNames[i] == "label")
                            {
                                continue;
                            }

                            opt.Update(i, exec.ArgmentArrays[i], exec.GradientArrays[i]);
                        }
                    }

                    sw.Stop();

                    var accuracy = new Accuracy();
                    valIter.Reset();
                    while (valIter.Next())
                    {
                        var dataBatch = valIter.GetDataBatch();
                        dataBatch.Data.CopyTo(args["X"]);
                        dataBatch.Label.CopyTo(args["label"]);
                        // Forward pass is enough as no gradient is needed when evaluating
                        exec.Forward(false);
                        accuracy.Update(dataBatch.Label, exec.Outputs[0]);
                    }

                    var duration = sw.ElapsedMilliseconds / 1000.0;
                    Logging.LG($"Epoch: {iter} {samples / duration} samples/sec Accuracy: {accuracy.Get()}");
                }
            }

            MXNet.MXNotifyShutdown();
        }
        public static void Run()
        {
            //Logistic Regression is one of the first models newcomers to Deep Learning are implementing.
            //The focus of this tutorial is to show how to do logistic regression using Gluon API.

            var ctx             = mx.Cpu();
            int train_data_size = 1000;
            int val_data_size   = 100;

            var(train_x, train_ground_truth_class) = GetRandomState(train_data_size, ctx);
            var train_dataset = new ArrayDataset((train_x, train_ground_truth_class));

            train_dataloader = new DataLoader(train_dataset, batch_size: batch_size, shuffle: true);

            var(val_x, val_ground_truth_class) = GetRandomState(val_data_size, ctx);
            var val_dataset = new ArrayDataset((val_x, val_ground_truth_class));

            val_dataloader = new DataLoader(val_dataset, batch_size: batch_size, shuffle: true);

            net = new HybridSequential();
            net.Add(new Dense(units: 10, activation: ActivationType.Relu));
            net.Add(new Dense(units: 10, activation: ActivationType.Relu));
            net.Add(new Dense(units: 10, activation: ActivationType.Relu));
            net.Add(new Dense(units: 1));

            net.Initialize(new Xavier());
            loss    = new SigmoidBinaryCrossEntropyLoss();
            trainer = new Trainer(net.CollectParams(), new SGD(learning_rate: 0.1f));

            accuracy = new Accuracy();
            f1       = new F1();

            int   epochs    = 10;
            float threshold = 0.5f;

            foreach (var e in Enumerable.Range(0, epochs))
            {
                var avg_train_loss = TrainModel() / train_data_size;
                var avg_val_loss   = ValidateModel(threshold) / val_data_size;
                Console.WriteLine($"Epoch: {e}, Training loss: {avg_train_loss}, Validation loss: {avg_val_loss}, Validation accuracy: {accuracy.Get().Item2}, F1 score: {f1.Get().Item2}");
            }
        }
Exemple #6
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        private static void Main()
        {
            /*basic config*/
            const int   batchSize    = 256;
            const int   maxEpo       = 100;
            const float learningRate = 1e-4f;
            const float weightDecay  = 1e-4f;

            /*context and net symbol*/
            var ctx = Context.Gpu();
            var net = AlexnetSymbol(2);

            /*args_map and aux_map is used for parameters' saving*/
            var argsMap = new Dictionary <string, NDArray>();
            var auxMap  = new Dictionary <string, NDArray>();

            /*we should tell mxnet the shape of data and label*/
            argsMap["data"]  = new NDArray(new Shape(batchSize, 3, 256, 256), ctx);
            argsMap["label"] = new NDArray(new Shape(batchSize), ctx);

            /*with data and label, executor can be generated varmatically*/
            using (var exec = net.SimpleBind(ctx, argsMap))
            {
                var argNames            = net.ListArguments();
                var auxiliaryDictionary = exec.AuxiliaryDictionary();
                var argmentDictionary   = exec.ArgmentDictionary();

                /*if fine tune from some pre-trained model, we should load the parameters*/
                // NDArray.Load("./model/alex_params_3", nullptr, &args_map);
                /*else, we should use initializer Xavier to init the params*/
                var xavier = new Xavier(RandType.Gaussian, FactorType.In, 2.34f);
                foreach (var arg in argmentDictionary)
                {
                    /*be careful here, the arg's name must has some specific ends or starts for
                     * initializer to call*/
                    xavier.Operator(arg.Key, arg.Value);
                }

                /*print out to check the shape of the net*/
                foreach (var s in net.ListArguments())
                {
                    Logging.LG(s);

                    var sb = new StringBuilder();
                    var k  = argmentDictionary[s].GetShape();
                    foreach (var i in k)
                    {
                        sb.Append($"{i} ");
                    }

                    Logging.LG(sb.ToString());
                }

                /*these binary files should be generated using im2rc tools, which can be found
                 * in mxnet/bin*/
                var trainIter = new MXDataIter("ImageRecordIter")
                                .SetParam("path_imglist", "./data/train.lst")
                                .SetParam("path_imgrec", "./data/train.rec")
                                .SetParam("data_shape", new Shape(3, 256, 256))
                                .SetParam("batch_size", batchSize)
                                .SetParam("shuffle", 1)
                                .CreateDataIter();
                var valIter = new MXDataIter("ImageRecordIter")
                              .SetParam("path_imglist", "./data/val.lst")
                              .SetParam("path_imgrec", "./data/val.rec")
                              .SetParam("data_shape", new Shape(3, 256, 256))
                              .SetParam("batch_size", batchSize)
                              .CreateDataIter();

                var opt = OptimizerRegistry.Find("ccsgd");
                opt.SetParam("momentum", 0.9)
                .SetParam("rescale_grad", 1.0 / batchSize)
                .SetParam("clip_gradient", 10)
                .SetParam("lr", learningRate)
                .SetParam("wd", weightDecay);

                var accuracyTrain = new Accuracy();
                var accuracyVal   = new Accuracy();
                var loglossVal    = new LogLoss();
                for (var iter = 0; iter < maxEpo; ++iter)
                {
                    Logging.LG($"Train Epoch: {iter}");
                    /*reset the metric every epoch*/
                    accuracyTrain.Reset();
                    /*reset the data iter every epoch*/
                    trainIter.Reset();
                    while (trainIter.Next())
                    {
                        var batch = trainIter.GetDataBatch();
                        Logging.LG($"{trainIter.GetDataBatch().Index.Length}");
                        /*use copyto to feed new data and label to the executor*/
                        batch.Data.CopyTo(argmentDictionary["data"]);
                        batch.Label.CopyTo(argmentDictionary["label"]);
                        exec.Forward(true);
                        exec.Backward();
                        for (var i = 0; i < argNames.Count; ++i)
                        {
                            if (argNames[i] == "data" || argNames[i] == "label")
                            {
                                continue;
                            }
                            opt.Update(i, exec.ArgmentArrays[i], exec.GradientArrays[i]);
                        }

                        NDArray.WaitAll();
                        accuracyTrain.Update(batch.Label, exec.Outputs[0]);
                    }
                    Logging.LG($"ITER: {iter} Train Accuracy: {accuracyTrain.Get()}");

                    Logging.LG($"Val Epoch: {iter}");
                    accuracyVal.Reset();
                    valIter.Reset();
                    loglossVal.Reset();
                    while (valIter.Next())
                    {
                        var batch = valIter.GetDataBatch();
                        Logging.LG($"{valIter.GetDataBatch().Index.Length}");
                        batch.Data.CopyTo(argmentDictionary["data"]);
                        batch.Label.CopyTo(argmentDictionary["label"]);
                        exec.Forward(false);
                        NDArray.WaitAll();
                        accuracyVal.Update(batch.Label, exec.Outputs[0]);
                        loglossVal.Update(batch.Label, exec.Outputs[0]);
                    }
                    Logging.LG($"ITER: {iter} Val Accuracy: {accuracyVal.Get()}");
                    Logging.LG($"ITER: {iter} Val LogLoss: {loglossVal.Get()}");

                    /*save the parameters*/
                    var savePathParam = $"./model/alex_param_{iter}";
                    var saveArgs      = argmentDictionary;
                    /*we do not want to save the data and label*/
                    if (saveArgs.ContainsKey("data"))
                    {
                        saveArgs.Remove("data");
                    }
                    if (saveArgs.ContainsKey("label"))
                    {
                        saveArgs.Remove("label");
                    }

                    /*the alexnet does not get any aux array, so we do not need to save
                     * aux_map*/
                    Logging.LG($"ITER: {iter} Saving to...{savePathParam}");
                    NDArray.Save(savePathParam, saveArgs);
                }
                /*don't foget to release the executor*/
            }

            MXNet.MXNotifyShutdown();
        }
Exemple #7
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        private static void Main()
        {
            /*setup basic configs*/
            const int   W            = 28;
            const int   H            = 28;
            const int   batchSize    = 128;
            const int   maxEpoch     = 100;
            const float learningRate = 1e-4f;
            const float weightDecay  = 1e-4f;

            var contest = Context.Gpu();

            var lenet   = LenetSymbol();
            var argsMap = new SortedDictionary <string, NDArray>();

            argsMap["data"]       = new NDArray(new Shape(batchSize, 1, W, H), contest);
            argsMap["data_label"] = new NDArray(new Shape(batchSize), contest);
            lenet.InferArgsMap(contest, argsMap, argsMap);

            argsMap["fc1_w"] = new NDArray(new Shape(500, 4 * 4 * 50), contest);
            NDArray.SampleGaussian(0, 1, argsMap["fc1_w"]);
            argsMap["fc2_b"] = new NDArray(new Shape(10), contest);
            argsMap["fc2_b"].Set(0);

            var trainIter = new MXDataIter("MNISTIter")
                            .SetParam("image", "./mnist_data/train-images-idx3-ubyte")
                            .SetParam("label", "./mnist_data/train-labels-idx1-ubyte")
                            .SetParam("batch_size", batchSize)
                            .SetParam("shuffle", 1)
                            .SetParam("flat", 0)
                            .CreateDataIter();
            var valIter = new MXDataIter("MNISTIter")
                          .SetParam("image", "./mnist_data/t10k-images-idx3-ubyte")
                          .SetParam("label", "./mnist_data/t10k-labels-idx1-ubyte")
                          .CreateDataIter();

            var opt = OptimizerRegistry.Find("ccsgd");

            opt.SetParam("momentum", 0.9)
            .SetParam("rescale_grad", 1.0)
            .SetParam("clip_gradient", 10)
            .SetParam("lr", learningRate)
            .SetParam("wd", weightDecay);

            using (var exec = lenet.SimpleBind(contest, argsMap))
            {
                var argNames = lenet.ListArguments();

                // Create metrics
                var trainAccuracy = new Accuracy();
                var valAccuracy   = new Accuracy();

                var sw = new Stopwatch();
                for (var iter = 0; iter < maxEpoch; ++iter)
                {
                    var samples = 0;
                    trainIter.Reset();
                    trainAccuracy.Reset();

                    sw.Restart();

                    while (trainIter.Next())
                    {
                        samples += batchSize;
                        var dataBatch = trainIter.GetDataBatch();

                        dataBatch.Data.CopyTo(argsMap["data"]);
                        dataBatch.Label.CopyTo(argsMap["data_label"]);
                        NDArray.WaitAll();

                        // Compute gradients
                        exec.Forward(true);
                        exec.Backward();

                        // Update parameters
                        for (var i = 0; i < argNames.Count; ++i)
                        {
                            if (argNames[i] == "data" || argNames[i] == "data_label")
                            {
                                continue;
                            }
                            opt.Update(i, exec.ArgmentArrays[i], exec.GradientArrays[i]);
                        }

                        // Update metric
                        trainAccuracy.Update(dataBatch.Label, exec.Outputs[0]);
                    }

                    // one epoch of training is finished
                    sw.Stop();
                    var duration = sw.ElapsedMilliseconds / 1000.0;
                    Logging.LG($"Epoch[{iter}] {samples / duration} samples/sec Train-Accuracy={trainAccuracy.Get()}");

                    valIter.Reset();
                    valAccuracy.Reset();

                    var accuracy = new Accuracy();
                    valIter.Reset();
                    while (valIter.Next())
                    {
                        var dataBatch = valIter.GetDataBatch();
                        dataBatch.Data.CopyTo(argsMap["data"]);
                        dataBatch.Label.CopyTo(argsMap["data_label"]);
                        NDArray.WaitAll();

                        // Only forward pass is enough as no gradient is needed when evaluating
                        exec.Forward(false);
                        NDArray.WaitAll();
                        accuracy.Update(dataBatch.Label, exec.Outputs[0]);
                        valAccuracy.Update(dataBatch.Label, exec.Outputs[0]);
                    }

                    Logging.LG($"Epoch[{iter}] Val-Accuracy={valAccuracy.Get()}");
                }
            }

            MXNet.MXNotifyShutdown();
        }
Exemple #8
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        private static void Main(string[] args)
        {
            //var minScore = float.Parse(args[0], NumberStyles.Float, null);
            var minScore = 0.9f;

            const int   imageSize    = 28;
            var         layers       = new[] { 128, 64, 10 };
            const int   batchSize    = 100;
            const int   maxEpoch     = 10;
            const float learningRate = 0.1f;
            const float weightDecay  = 1e-2f;

            var trainIter = new MXDataIter("MNISTIter")
                            .SetParam("image", "./mnist_data/train-images-idx3-ubyte")
                            .SetParam("label", "./mnist_data/train-labels-idx1-ubyte")
                            .SetParam("batch_size", batchSize)
                            .SetParam("flat", 1)
                            .CreateDataIter();
            var valIter = new MXDataIter("MNISTIter")
                          .SetParam("image", "./mnist_data/t10k-images-idx3-ubyte")
                          .SetParam("label", "./mnist_data/t10k-labels-idx1-ubyte")
                          .SetParam("batch_size", batchSize)
                          .SetParam("flat", 1)
                          .CreateDataIter();

            var net = Mlp(layers);

            var ctx = Context.Cpu();  // Use GPU for training

            var dictionary = new Dictionary <string, NDArray>();

            dictionary["X"]     = new NDArray(new Shape(batchSize, imageSize * imageSize), ctx);
            dictionary["label"] = new NDArray(new Shape(batchSize), ctx);
            // Let MXNet infer shapes of other parameters such as weights
            net.InferArgsMap(ctx, dictionary, dictionary);

            // Initialize all parameters with uniform distribution U(-0.01, 0.01)
            var initializer = new Uniform(0.01f);

            foreach (var arg in dictionary)
            {
                // arg.first is parameter name, and arg.second is the value
                initializer.Operator(arg.Key, arg.Value);
            }

            // Create sgd optimizer
            var opt = OptimizerRegistry.Find("sgd");

            opt.SetParam("rescale_grad", 1.0 / batchSize)
            .SetParam("lr", learningRate)
            .SetParam("wd", weightDecay);
            var lrSch = new UniquePtr <LRScheduler>(new FactorScheduler(5000, 0.1f));

            opt.SetLearningRateScheduler(lrSch);

            // Create executor by binding parameters to the model
            using (var exec = net.SimpleBind(ctx, dictionary))
            {
                var argNames = net.ListArguments();

                float score = 0;
                // Start training

                var sw = new Stopwatch();
                for (var iter = 0; iter < maxEpoch; ++iter)
                {
                    var samples = 0;
                    trainIter.Reset();

                    sw.Restart();
                    while (trainIter.Next())
                    {
                        samples += batchSize;
                        var dataBatch = trainIter.GetDataBatch();
                        // Data provided by DataIter are stored in memory, should be copied to GPU first.
                        dataBatch.Data.CopyTo(dictionary["X"]);
                        dataBatch.Label.CopyTo(dictionary["label"]);
                        // CopyTo is imperative, need to wait for it to complete.
                        NDArray.WaitAll();

                        // Compute gradients
                        exec.Forward(true);
                        exec.Backward();
                        // Update parameters
                        for (var i = 0; i < argNames.Count; ++i)
                        {
                            if (argNames[i] == "X" || argNames[i] == "label")
                            {
                                continue;
                            }

                            var weight = exec.ArgmentArrays[i];
                            var grad   = exec.GradientArrays[i];
                            opt.Update(i, weight, grad);
                        }
                    }

                    sw.Stop();

                    var acc = new Accuracy();
                    valIter.Reset();
                    while (valIter.Next())
                    {
                        var dataBatch = valIter.GetDataBatch();
                        dataBatch.Data.CopyTo(dictionary["X"]);
                        dataBatch.Label.CopyTo(dictionary["label"]);
                        NDArray.WaitAll();
                        // Only forward pass is enough as no gradient is needed when evaluating
                        exec.Forward(false);
                        acc.Update(dataBatch.Label, exec.Outputs[0]);
                    }

                    var duration = sw.ElapsedMilliseconds / 1000.0;
                    var message  = $"Epoch: {iter} {samples / duration} samples/sec Accuracy: {acc.Get()}";
                    Logging.LG(message);
                    score = acc.Get();
                }

                MXNet.MXNotifyShutdown();
                var ret = score >= minScore ? 0 : 1;
                Console.WriteLine($"{ret}");
            }
        }
Exemple #9
0
        private static void Main()
        {
            const uint  batchSize    = 50;
            const uint  maxEpoch     = 100;
            const float learningRate = 1e-4f;
            const float weightDecay  = 1e-4f;

            var googlenet = GoogleNetSymbol(101 + 1); // +1 is BACKGROUND_Google
            var argsMap   = new Dictionary <string, NDArray>();
            var auxMap    = new Dictionary <string, NDArray>();

            // change device type if you want to use GPU
            var context = Context.Cpu();

            argsMap["data"]       = new NDArray(new Shape(batchSize, 3, 256, 256), context);
            argsMap["data_label"] = new NDArray(new Shape(batchSize), context);
            googlenet.InferArgsMap(Context.Cpu(), argsMap, argsMap);

            var trainIter = new MXDataIter("ImageRecordIter")
                            .SetParam("path_imglist", "train.lst")
                            .SetParam("path_imgrec", "train.rec")
                            .SetParam("data_shape", new Shape(3, 256, 256))
                            .SetParam("batch_size", batchSize)
                            .SetParam("shuffle", 1)
                            .CreateDataIter();

            var valIter = new MXDataIter("ImageRecordIter")
                          .SetParam("path_imglist", "val.lst")
                          .SetParam("path_imgrec", "val.rec")
                          .SetParam("data_shape", new Shape(3, 256, 256))
                          .SetParam("batch_size", batchSize)
                          .CreateDataIter();

            var opt = OptimizerRegistry.Find("ccsgd");

            opt.SetParam("momentum", 0.9)
            .SetParam("rescale_grad", 1.0 / batchSize)
            .SetParam("clip_gradient", 10)
            .SetParam("lr", learningRate)
            .SetParam("wd", weightDecay);

            using (var exec = googlenet.SimpleBind(Context.Cpu(), argsMap))
            {
                var argNames = googlenet.ListArguments();

                for (var iter = 0; iter < maxEpoch; ++iter)
                {
                    Logging.LG($"Epoch: {iter}");

                    trainIter.Reset();
                    while (trainIter.Next())
                    {
                        var dataBatch = trainIter.GetDataBatch();
                        dataBatch.Data.CopyTo(argsMap["data"]);
                        dataBatch.Label.CopyTo(argsMap["data_label"]);
                        NDArray.WaitAll();
                        exec.Forward(true);
                        exec.Backward();
                        for (var i = 0; i < argNames.Count; ++i)
                        {
                            if (argNames[i] == "data" || argNames[i] == "data_label")
                            {
                                continue;
                            }

                            var weight = exec.ArgmentArrays[i];
                            var grad   = exec.GradientArrays[i];
                            opt.Update(i, weight, grad);
                        }
                    }

                    var acu = new Accuracy();
                    valIter.Reset();
                    while (valIter.Next())
                    {
                        var dataBatch = valIter.GetDataBatch();
                        dataBatch.Data.CopyTo(argsMap["data"]);
                        dataBatch.Label.CopyTo(argsMap["data_label"]);
                        NDArray.WaitAll();
                        exec.Forward(false);
                        NDArray.WaitAll();
                        acu.Update(dataBatch.Label, exec.Outputs[0]);
                    }

                    Logging.LG($"Accuracy: {acu.Get()}");
                }
            }

            MXNet.MXNotifyShutdown();
        }