block6.fs

// set up a training pipeline
let pipeline = 
    EstimatorChain()

        // step 1: convert the label value to a boolean
        .Append(
            context.Transforms.CustomMapping(
                Action<HeartData, ToLabel>(fun input output -> output.Label <- input.Diagnosis > 0.0f),
                "LabelMapping"))

        // step 2: concatenate all feature columns
        .Append(context.Transforms.Concatenate("Features", "Age", "Sex", "Cp", "TrestBps", "Chol", "Fbs", "RestEcg", "Thalac", "Exang", "OldPeak", "Slope", "Ca", "Thal"))

        // step 3: set up a fast tree learner
        .Append(context.BinaryClassification.Trainers.FastTree())

// train the model
let model = partitions.TrainSet |> pipeline.Fit

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