How to: Draw a Custom Function in the 2D Scatter Line Chart

• Jun 07, 2019
• 2 minutes to read

This example demonstrates how to draw an Archimedian Spiral function in the Scatter Line chart. To do this, it is necessary to add a LineScatterSeries2D object to the diagram’s Diagram.Series collection and then programmatically add series points to it.

For more information, see the CreateArchimedianSpiralPoints method’s implementation below.

Note

A complete sample project is available at https://github.com/DevExpress-Examples/how-to-draw-a-custom-function-in-the-2d-scatter-line-chart-e3512.

MainWindow.xaml.cs

using System;
using System.Windows;
using DevExpress.Xpf.Charts;

namespace ScatterLineChartWithCustomFunction {

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

        void CreateArchimedianSpiralPoints() {
            for (int i = 0; i < 720; i += 15) {
                double t = (double)i / 180 * Math.PI;
                double x = t * Math.Cos(t);
                double y = t * Math.Sin(t);
                ArchimedianSpiral.Points.Add(new SeriesPoint(x, y));
            }
        }
    }
}

MainWindow.xaml

<Window x:Class="ScatterLineChartWithCustomFunction.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
        xmlns:dxc="http://schemas.devexpress.com/winfx/2008/xaml/charts"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <dxc:ChartControl>
            <dxc:ChartControl.Diagram>
                <dxc:XYDiagram2D>
                    <dxc:XYDiagram2D.Series>
                        <dxc:LineScatterSeries2D x:Name="ArchimedianSpiral" ArgumentScaleType="Numerical">
                            <dxc:LineScatterSeries2D.Label>
                                <dxc:SeriesLabel Visible="False" />
                            </dxc:LineScatterSeries2D.Label>
                        </dxc:LineScatterSeries2D>
                    </dxc:XYDiagram2D.Series>
                    <dxc:XYDiagram2D.AxisX>
                        <dxc:AxisX2D GridLinesVisible="True" />
                    </dxc:XYDiagram2D.AxisX>
                    <dxc:XYDiagram2D.AxisY>
                        <dxc:AxisY2D GridLinesMinorVisible="True" />
                    </dxc:XYDiagram2D.AxisY>
                </dxc:XYDiagram2D>
            </dxc:ChartControl.Diagram>
            <dxc:ChartControl.Titles>
                <dxc:Title Dock="Top" HorizontalAlignment="Center" Content="Archimedian Spiral Function" />
            </dxc:ChartControl.Titles>
        </dxc:ChartControl>
    </Grid>
</Window>

MainWindow.xaml.vb

Imports Microsoft.VisualBasic
Imports System
Imports System.Windows
Imports DevExpress.Xpf.Charts

Namespace ScatterLineChartWithCustomFunction

    Partial Public Class MainWindow
        Inherits Window
        Public Sub New()
            InitializeComponent()
            CreateArchimedianSpiralPoints()
        End Sub

        Private Sub CreateArchimedianSpiralPoints()
            For i As Integer = 0 To 719 Step 15
                Dim t As Double = CDbl(i) / 180 * Math.PI
                Dim x As Double = t * Math.Cos(t)
                Dim y As Double = t * Math.Sin(t)
                ArchimedianSpiral.Points.Add(New SeriesPoint(x, y))
            Next i
        End Sub
    End Class
End Namespace