block6.csharp.cs

/// <summary>
/// The main program class.
/// </summary>
public class Program
{
    // filenames for data set
    private static string dataPath = Path.Combine(Environment.CurrentDirectory, "spam.tsv");

    /// <summary>
    /// The main program entry point.
    /// </summary>
    /// <param name="args">The command line parameters.</param>
    static void Main(string[] args)
    {
        // set up a machine learning context
        var context = new MLContext();

        // load the spam dataset in memory
        Console.WriteLine("Loading data...");
        var data = context.Data.LoadFromTextFile<SpamData>(
            path: dataPath, 
            hasHeader: true, 
            separatorChar: '\t');

        // use 80% for training and 20% for testing
        var partitions = context.Data.TrainTestSplit(data, testFraction: 0.3);

        // set up a pipeline to featurize the text
        Console.WriteLine("Featurizing text...");
        var pipeline = context.Transforms.Text.FeaturizeText(
                outputColumnName: "Features", 
                inputColumnName: nameof(SpamData.Message));

        // the rest of the code goes here...
    }
}