/// <summary>
/// Program entry point.
/// </summary>
/// <param name="app">Holds arguments and other info.</param>
public void Execute(IExampleInterface app)
{
// Download the data that we will attempt to model.
string filename = DownloadData(app.Args);
// Define the format of the data file.
// This area will change, depending on the columns and
// format of the file that you are trying to model.
var format = new CSVFormat('.', ' '); // decimal point and space separated
IVersatileDataSource source = new CSVDataSource(filename, false, format);
var data = new VersatileMLDataSet(source);
data.NormHelper.Format = format;
ColumnDefinition columnMPG = data.DefineSourceColumn("mpg", 0, ColumnType.Continuous);
ColumnDefinition columnCylinders = data.DefineSourceColumn("cylinders", 1, ColumnType.Ordinal);
// It is very important to predefine ordinals, so that the order is known.
columnCylinders.DefineClass(new[] { "3", "4", "5", "6", "8" });
data.DefineSourceColumn("displacement", 2, ColumnType.Continuous);
ColumnDefinition columnHorsePower = data.DefineSourceColumn("horsepower", 3, ColumnType.Continuous);
data.DefineSourceColumn("weight", 4, ColumnType.Continuous);
data.DefineSourceColumn("acceleration", 5, ColumnType.Continuous);
ColumnDefinition columnModelYear = data.DefineSourceColumn("model_year", 6, ColumnType.Ordinal);
columnModelYear.DefineClass(new[]
{ "70", "71", "72", "73", "74", "75", "76", "77", "78", "79", "80", "81", "82" });
data.DefineSourceColumn("origin", 7, ColumnType.Nominal);
// Define how missing values are represented.
data.NormHelper.DefineUnknownValue("?");
data.NormHelper.DefineMissingHandler(columnHorsePower, new MeanMissingHandler());
// Analyze the data, determine the min/max/mean/sd of every column.
data.Analyze();
// Map the prediction column to the output of the model, and all
// other columns to the input.
data.DefineSingleOutputOthersInput(columnMPG);
// Create feedforward neural network as the model type. MLMethodFactory.TYPE_FEEDFORWARD.
// You could also other model types, such as:
// MLMethodFactory.SVM: Support Vector Machine (SVM)
// MLMethodFactory.TYPE_RBFNETWORK: RBF Neural Network
// MLMethodFactor.TYPE_NEAT: NEAT Neural Network
// MLMethodFactor.TYPE_PNN: Probabilistic Neural Network
var model = new EncogModel(data);
model.SelectMethod(data, MLMethodFactory.TypeFeedforward);
// Send any output to the console.
model.Report = new ConsoleStatusReportable();
// Now normalize the data. Encog will automatically determine the correct normalization
// type based on the model you chose in the last step.
data.Normalize();
// Hold back some data for a final validation.
// Shuffle the data into a random ordering.
// Use a seed of 1001 so that we always use the same holdback and will get more consistent results.
model.HoldBackValidation(0.3, true, 1001);
// Choose whatever is the default training type for this model.
model.SelectTrainingType(data);
// Use a 5-fold cross-validated train. Return the best method found.
var bestMethod = (IMLRegression)model.Crossvalidate(5, true);
// Display the training and validation errors.
Console.WriteLine(@"Training error: " + model.CalculateError(bestMethod, model.TrainingDataset));
Console.WriteLine(@"Validation error: " + model.CalculateError(bestMethod, model.ValidationDataset));
// Display our normalization parameters.
NormalizationHelper helper = data.NormHelper;
Console.WriteLine(helper.ToString());
// Display the final model.
Console.WriteLine("Final model: " + bestMethod);
// Loop over the entire, original, dataset and feed it through the model.
// This also shows how you would process new data, that was not part of your
// training set. You do not need to retrain, simply use the NormalizationHelper
// class. After you train, you can save the NormalizationHelper to later
// normalize and denormalize your data.
source.Close();
var csv = new ReadCSV(filename, false, format);
var line = new String[7];
IMLData input = helper.AllocateInputVector();
while (csv.Next())
{
var result = new StringBuilder();
line[0] = csv.Get(1);
line[1] = csv.Get(2);
line[2] = csv.Get(3);
line[3] = csv.Get(4);
line[4] = csv.Get(5);
line[5] = csv.Get(6);
line[6] = csv.Get(7);
String correct = csv.Get(0);
helper.NormalizeInputVector(line, ((BasicMLData)input).Data, false);
IMLData output = bestMethod.Compute(input);
String irisChosen = helper.DenormalizeOutputVectorToString(output)[0];
result.Append(line);
result.Append(" -> predicted: ");
result.Append(irisChosen);
result.Append("(correct: ");
result.Append(correct);
result.Append(")");
Console.WriteLine(result.ToString());
}
csv.Close();
// Delete data file and shut down.
File.Delete(filename);
EncogFramework.Instance.Shutdown();
}
