public MainWindow()
        {
            DataContext = this;

            Graph = new PlotModel();
            chart = new ChartAdapter(Graph);
            chart.SetLinearScale(AxisProperty.Both);

            loader = new SchemeLoader();
            loader.Import(@"Scheme.rkt");

            var evaluator = new ProxySchemeEvaluator();
            var schemeCalculator = new SchemeCalculator(evaluator);
            transformer = new LineSeriesTransformer((IFunctionPlotter)schemeCalculator,(ICalculate)schemeCalculator);

            modelCollection = new ObservableLineSeriesModelCollection();
            modelCollection.CollectionChanged += ModelChanged;

            ModelViewCollection = new ObservableLineSeriesViewModelCollection();
            ModelViewCollection.AddModel(new LineSeriesViewModel
                                      {
                                          Function = "(lambda (x) x)",
                                          Name = "Example 1",
                                      });
            InitializeComponent();
        }