trouble binding LineSeries to Array

Hi--

I'm trying to figure out the most efficient way to load a LineChart with data.

I'd like to be able to load data directly from an array without needing to create and maintain a Collection of explicitly defined objects with dependency properties.

The following data binding descriptions and code sample from the 'Specifying Items' and 'Axes' documentation imply that this is possible:

The ItemsSource property on each series can be set to any collection of objects, including custom objects, as long as the collection implements IEnumerable.

....

We can specify that the Y values should be pulled from the Amount property by setting YPath to "Amount". If we want to use the index in the collection as our X values, then we do not need to set XPath.

<charts:XYChart Width="300" Height="200">
    <charts:XYChart.XAxes>
        <XYDateTimeAxis&quot;/>
    </charts:XYChart.XAxes>
    <charts:XYChart.YAxes>
        <XYDoubleAxis/>
    </charts:XYChart.YAxes>
    <charts:AreaSeries ItemsSource="{Binding}" XPath="MyDateProperty" YPath="MyDoubleProperty" />
</charts:XYChart>

 When I try, however, I get no chart or data. Adding the XYDoubleAxis does not help.

I know that the Chart can get the data, however, because I can bind ItemSource directly to one of the Arrays (as shown in the example below), but this binds to both the X and Y axes instead of just Y. (btw, this behavior seems unusual to me. Charts in other visualization toolkits I have used, when displaying a single array of data, would bind data values to the YAxis and use the array offsets along the X axis).

Any advice would be appreciated.

Here's my XAML:

<Window x:Class="ArrayDataTest.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:charts="http://schemas.actiprosoftware.com/winfx/xaml/charts"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="*" />
            <RowDefinition Height="*" />
        </Grid.RowDefinitions>
        <charts:XYChart x:Name="chart1" >
            <charts:LineSeries ItemsSource="{Binding}" XPath="X" YPath="Y" />
        </charts:XYChart>
        <charts:XYChart x:Name="chart2" Grid.Row="1">
            <charts:LineSeries ItemsSource="{Binding Y}" />
        </charts:XYChart>
    </Grid>
</Window>

 and the C#:

namespace ArrayDataTest
{
    public class WpfViewModel : INotifyPropertyChanged
    {
        private Double[] x;
        public Double[] X
        {
            get { return x; }
            set
            {
                x = value;
                OnPropertyChanged("X");
            }
        }

        private Double[] y;
        public Double[] Y
        {
            get { return y; }
            set
            {
                y = value;
                OnPropertyChanged("Y");
            }
        }

        public WpfViewModel(int size)
        {
            x = new Double[size];
            y = new Double[size];
            initializeData(size);
        }

        private void initializeData(int size)
        {
            double m;
            double dt = 1;
            for (int i = 0; i < size; i++)
            {
                m = i * dt;
                this.x[i] = m;
                this.y[i] = Math.Sin(m) * 2 * Math.PI;
            }
        }

        public event PropertyChangedEventHandler PropertyChanged;
        protected void OnPropertyChanged(string name)
        {
            PropertyChangedEventHandler handler = PropertyChanged;
            if (handler != null)
            {
                Console.WriteLine("PropertyChangedEventHandler: " + name);
                handler(this, new PropertyChangedEventArgs(name));
            }
        }
    }

    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            this.DataContext = new WpfViewModel(500);
            InitializeComponent();
        }
    }
}

Thanks!

--jon