Graham,

it helps! It's working! Thank you very much!!

Here is an example of how you can convert a data table to a collection of a nominal type and bind it to the chart.
The Xaml:

<igChart:XamDataChart x:Name="theChart">
            <igChart:XamDataChart.Axes>
                <igChart:NumericYAxis x:Name="yAxis" />
                <igChart:CategoryXAxis 
                    x:Name="xAxis"
                    ItemsSource="{Binding}"
                    Label="{}{Label}"/>
            </igChart:XamDataChart.Axes>
            <igChart:XamDataChart.Series>
                <igChart:ColumnSeries
                    x:Name="series"
                    ItemsSource="{Binding}"
                    XAxis="{Binding ElementName=xAxis}"
                    YAxis="{Binding ElementName=yAxis}"
                    ValueMemberPath="Value" />
            </igChart:XamDataChart.Series>
        </igChart:XamDataChart>

And the code behind:

public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();

            var data = from row in GetTestData()
                       .Rows.OfType<DataRow>()
                       select new DataItem()
                       {
                           Label = (string)row["Label"],
                           Value = (double)row["Value"]
                       };

            DataContext = data;
        }

        public DataTable GetTestData()
        {
            DataTable testData = new DataTable();
            testData.Columns.Add(new DataColumn("Label", typeof(string)));
            testData.Columns.Add(new DataColumn("Value", typeof(double)));

            DataRow dr = testData.NewRow();
            dr["Label"] = "A";
            dr["Value"] = 1;
            testData.Rows.Add(dr);

            dr = testData.NewRow();
            dr["Label"] = "B";
            dr["Value"] = 2;
            testData.Rows.Add(dr);

            dr = testData.NewRow();
            dr["Label"] = "C";
            dr["Value"] = 3;
            testData.Rows.Add(dr);

            dr = testData.NewRow();
            dr["Label"] = "D";
            dr["Value"] = 4;
            testData.Rows.Add(dr);

            return testData;
        }
    }

    public class DataItem
    {
        public string Label { get; set; }
        public double Value { get; set; }
    }	

Hope this helps!
-Graham

Graham,

thanks for the reply.

It would be very nice to bind through DataTable.

I tried to use nominal class as you suggested, but all my attempts were unsuccessful. Could you give me a little working example that draws a broken line by 3-5 points?