示例#1
0
        static void Main(string[] args)
        {
            TextLoader loader = TextLoader.Create(typeof(IrisData));

            loader.Separator = ",";

            IDataView trainingData = loader.Read("iris-data.txt");

            var estimator = new ValueToKeyMappingEstimator("Label")
                            .Append(new ColumnConcatenatingEstimator("Features", "SepalLength", "SepalWidth", "PetalLength", "PetalWidth"))
                            .Append(new SdcaMultiClassTrainer())
                            .Append(new KeyToValueMappingEstimator("PredictedLabel"));

            var model = estimator.Train <IrisData, IrisPrediction>(trainingData);

            IrisData newInput = new IrisData()
            {
                SepalLength = 3.3f,
                SepalWidth  = 1.6f,
                PetalLength = 0.2f,
                PetalWidth  = 5.1f,
            };
            IrisPrediction prediction = model.Predict(newInput);

            Console.WriteLine($"Predicted flower type is: {prediction.PredictedLabel}");
        }
示例#2
0
        static void Main(string[] args)
        {
            TextLoader loader       = TextLoader.Create(typeof(IrisData), separator: ",");
            IDataView  trainingData = loader.Read("iris-data.txt");

            var pipeline = new EstimatorChain();

            pipeline.Add(new ValueToKeyMappingEstimator(nameof(IrisData.Label)));
            pipeline.Add(new ColumnConcatenatingEstimator(
                             inputColumns: new[]
            {
                nameof(IrisData.SepalLength),
                nameof(IrisData.SepalWidth),
                nameof(IrisData.PetalLength),
                nameof(IrisData.PetalWidth)
            },
                             outputColumn: DefaultColumnNames.Features));
            pipeline.Add(new SdcaMultiClassTrainer(
                             featureColumn: DefaultColumnNames.Features,
                             labelColumn: nameof(IrisData.Label),
                             predictedLabelColumn: nameof(IrisPrediction.PredictedLabel)));
            pipeline.Add(new KeyToValueMappingEstimator(nameof(IrisPrediction.PredictedLabel)));

            var model = pipeline.Fit(trainingData);

            IrisData newInput = new IrisData()
            {
                SepalLength = 3.3f,
                SepalWidth  = 1.6f,
                PetalLength = 0.2f,
                PetalWidth  = 5.1f,
            };
            IrisPrediction prediction = model
                                        .MakePredictionFunction <IrisData, IrisPrediction>()
                                        .Predict(newInput);

            Console.WriteLine($"Predicted flower type is: {prediction.PredictedLabel}");
        }
示例#3
0
        static void Main(string[] args)
        {
            // STEP 2: Create a ML.NET environment
            var       mlContext = new MLContext();
            Random    rnd       = new Random();
            Stopwatch sw        = new Stopwatch();

            Write("Loading dataset... ");
            sw.Start();
            // If working in Visual Studio, make sure the 'Copy to Output Directory'
            // property of iris-data.txt is set to 'Copy always'
            var reader = mlContext.Data.CreateTextLoader <IrisData>(separatorChar: ',', hasHeader: false);

            //https://en.m.wikipedia.org/wiki/Iris_flower_data_set
            IDataView trainingDataView = reader.Load("iris-data.txt");

            // STEP 3: Transform your data and add a learner
            // Assign numeric values to text in the "Label" column, because only
            // numbers can be processed during model training.
            // Add a learning algorithm to the pipeline. e.g.(What type of iris is this?)
            // Convert the Label back into original text (after converting to number in step 3)
            var pipeline = mlContext.Transforms.Conversion.MapValueToKey("Label")
                           .Append(mlContext.Transforms.Concatenate("Features", "SepalLength", "SepalWidth", "PetalLength", "PetalWidth"))
                           .Append(mlContext.MulticlassClassification.Trainers.StochasticDualCoordinateAscent(labelColumnName: "Label", featureColumnName: "Features"))
                           .Append(mlContext.Transforms.Conversion.MapKeyToValue("PredictedLabel"));

            sw.Stop();
            WriteLine($"{sw.Elapsed.Seconds*1000 + sw.Elapsed.Milliseconds} ms");

            // STEP 4: Train your model based on the data set
            Write("Training the model... ");
            sw.Restart();
            var model = pipeline.Fit(trainingDataView);

            sw.Stop();
            WriteLine($"{sw.Elapsed.Seconds*1000 + sw.Elapsed.Milliseconds} ms\n");

            do
            {
                // STEP 5: Use your model to make a prediction
                // You can change these numbers to test different predictions
                var iris = new IrisData()
                {
                    //                    SepalLength = 2.3f,
                    //                    SepalWidth = 1.6f,
                    //                    PetalLength = 0.2f,
                    //                    PetalWidth = 5.1f,
                    SepalLength = (float)rnd.NextDouble() * 3.6f + 4.3f,
                    SepalWidth  = (float)rnd.NextDouble() * 2.4f + 2.0f,
                    PetalLength = (float)rnd.NextDouble() * 5.9f + 1.0f,
                    PetalWidth  = (float)rnd.NextDouble() * 2.4f,
                };

                WriteLine($"Sepal length: {iris.SepalLength:F1} cm");
                WriteLine($"Sepal width:  {iris.SepalWidth:F1} cm");
                WriteLine($"Petal length: {iris.PetalLength:F1} cm");
                WriteLine($"Petal width:  {iris.PetalWidth:F1} cm");

                var prediction = model.CreatePredictionEngine <IrisData, IrisPrediction>(mlContext).Predict(iris);
                WriteLine($"Predicted flower type is: {prediction.PredictedLabels}");
                WriteLine("Esc to quit...\n");
            } while (ReadKey(true).Key != ConsoleKey.Escape);
        }