how to bind a list in numeric up down control(extended tool of wpf)

<Window x:Class="SlidingChart.Window3"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
               xmlns:ext="clr-namespace:eisiWare;assembly=NumericUpDown"

        Title="Window3" Height="300" Width="300" Loaded="Window_Loaded_1">
    <Grid>
        <
        <ext:NumericUpDown Name="cmb"  ValueChanged="cmb_ValueChanged"  ></ext:NumericUpDown>
        <;
    </Grid>
</Window>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;

namespace SlidingChart
{
    /// <summary>
    /// Interaction logic for Window3.xaml
    /// </summary>
    public partial class Window3 : Window
    {
        public Window3()
        {
            InitializeComponent();
        }

        private void ComboBox_SelectionChanged_1(object sender, SelectionChangedEventArgs e)
        {

        }

        private void cmb_ValueChanged(object sender, RoutedEventArgs e)
        {

        }

        private void Window_Loaded_1(object sender, RoutedEventArgs e)
        {
           int  ymax = 700;
            List<double> inp = new List<double>();
            for (double i = ymax; i >= 0; i--)
            {
                inp.Add(i);
            }

            cmb.DataContext = inp;
            
        
        }
    }
}