private void predictionBtn_Click(object sender, EventArgs e)
 {
     if (features != null && features.All(item => item != null))
     {
         DecisionNode node = tree.Predict(features);
         resultLabel.Text = PredictionToString(node);
     }
 }
 private static bool IsValidPredictionRow(Row row) =>
 row != null && row.All(item => item != null);