How to: Show Numerical Data Using a Logarithmic Scale

• Nov 13, 2018
• 2 minutes to read

This example demonstrates how to use a logarithmic scale in XtraCharts, which is disabled by default.

Note

The logarithmic scale is only compatible with the numerical scale type.

To enable it, simply set the AxisBase.Logarithmic property to true, and set the AxisBase.LogarithmicBase property to the value required in your scenario.

Form1.cs

using System;
using System.Windows.Forms;
using DevExpress.XtraCharts;

namespace LogarithmicScale {
    public partial class Form1 : Form {
        public Form1() {
            InitializeComponent();
        }

        private void btnLogarithm10_Click(object sender, EventArgs e) {
            AxisY axis = ((XYDiagram)chartControl1.Diagram).AxisY;
            axis.Logarithmic = true;
            axis.LogarithmicBase = 10;
            axis.WholeRange.AlwaysShowZeroLevel = false;
        }

        private void btnLogarithm100_Click(object sender, EventArgs e) {
            AxisY axis = ((XYDiagram)chartControl1.Diagram).AxisY;
            axis.Logarithmic = true;
            axis.LogarithmicBase = 100;
            axis.WholeRange.AlwaysShowZeroLevel = false;
        }

        private void btnDisableLogarithm_Click(object sender, EventArgs e) {
            AxisY axis = ((XYDiagram)chartControl1.Diagram).AxisY;
            axis.Logarithmic = false;
            axis.WholeRange.AlwaysShowZeroLevel = true;
        }
    }
}

Form1.vb

Imports System
Imports System.Windows.Forms
Imports DevExpress.XtraCharts

Namespace LogarithmicScale
    Partial Public Class Form1
        Inherits Form

        Public Sub New()
            InitializeComponent()
        End Sub

        Private Sub btnLogarithm10_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnLogarithm10.Click
            Dim axis As AxisY = CType(chartControl1.Diagram, XYDiagram).AxisY
            axis.Logarithmic = True
            axis.LogarithmicBase = 10
            axis.WholeRange.AlwaysShowZeroLevel = False
        End Sub

        Private Sub btnLogarithm100_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnLogarithm100.Click
            Dim axis As AxisY = CType(chartControl1.Diagram, XYDiagram).AxisY
            axis.Logarithmic = True
            axis.LogarithmicBase = 100
            axis.WholeRange.AlwaysShowZeroLevel = False
        End Sub

        Private Sub btnDisableLogarithm_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnDisableLogarithm.Click
            Dim axis As AxisY = CType(chartControl1.Diagram, XYDiagram).AxisY
            axis.Logarithmic = False
            axis.WholeRange.AlwaysShowZeroLevel = True
        End Sub
    End Class
End Namespace