Y-Axis IsLogarithmic Property and Pointmarks

[Taylor]

I have a chart which implements a Logarithmic Scale for the Y-Axis as described here:
http://www.telerik.com/help/wpf/radchart-features-axes-logarithmic-scale.html

I some cases, when the IsLogarithmic Property is toggled for Line Series types, the Point Marks become skewed.  The lines themselves seem to be plotted correctly, but the Point Marks will appear in their old positions.  This behavior only occurs for only certain data sets.

Below is an example which demonstrates the problem.

XAML:

<Window x:Class="LogarithmicScale.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:telerikChart="clr-namespace:Telerik.Windows.Controls;assembly=Telerik.Windows.Controls.Charting"
        xmlns:telerikCharting="clr-namespace:Telerik.Windows.Controls.Charting;assembly=Telerik.Windows.Controls.Charting"
        xmlns:example="clr-namespace:Telerik.Windows.Examples.Chart.LogarithmicScale"
        Title="MainWindow" Height="700" Width="900" WindowStartupLocation="CenterScreen">

    <Window.DataContext>
        <example:ExampleViewModel />
    </Window.DataContext>

    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto" />
            <RowDefinition Height="Auto" />
        </Grid.RowDefinitions>

        <CheckBox x:Name="ToggleLogModeCheckBox" Content="Use Logarithmic Y-Axis"
                  IsChecked="False" Margin="6" Grid.Row="0"
                  Checked="ToggleLogModeCheckBox_Checked"
                  Unchecked="ToggleLogModeCheckBox_Checked" />

        <telerikChart:RadChart x:Name="RadChart1" Grid.Row="1" ItemsSource="{Binding Data}">
            <telerikChart:RadChart.DefaultView>
                <telerikCharting:ChartDefaultView>
                    <telerikCharting:ChartDefaultView.ChartArea>
                        <telerikCharting:ChartArea LegendName="PrimaryLegend">
                            <telerikCharting:ChartArea.AxisX>
                                <telerikCharting:AxisX/>
                            </telerikCharting:ChartArea.AxisX>
                            <telerikCharting:ChartArea.AxisY>
                                <telerikCharting:AxisY x:Name="LogAxis"
                                         IsLogarithmic="False"
                                         Title="Total population" />
                            </telerikCharting:ChartArea.AxisY>
                        </telerikCharting:ChartArea>
                    </telerikCharting:ChartDefaultView.ChartArea>
                    <telerikCharting:ChartDefaultView.ChartLegend>
                        <telerikCharting:ChartLegend x:Name="PrimaryLegend"/>
                    </telerikCharting:ChartDefaultView.ChartLegend>
                </telerikCharting:ChartDefaultView>
            </telerikChart:RadChart.DefaultView>
            <telerikChart:RadChart.SeriesMappings>
                <telerikCharting:SeriesMapping CollectionIndex="0">
                    <telerikCharting:SeriesMapping.SeriesDefinition>
                        <telerikCharting:LineSeriesDefinition ShowItemLabels="False" />
                    </telerikCharting:SeriesMapping.SeriesDefinition>
                    <telerikCharting:SeriesMapping.ItemMappings>
                        <telerikCharting:ItemMapping FieldName="Population"
                                      DataPointMember="YValue" />
                        <telerikCharting:ItemMapping FieldName="Time"
                                      DataPointMember="XValue" />
                    </telerikCharting:SeriesMapping.ItemMappings>
                </telerikCharting:SeriesMapping>
                <telerikCharting:SeriesMapping CollectionIndex="1">
                    <telerikCharting:SeriesMapping.SeriesDefinition>
                        <telerikCharting:LineSeriesDefinition ShowItemLabels="False" />
                    </telerikCharting:SeriesMapping.SeriesDefinition>
                    <telerikCharting:SeriesMapping.ItemMappings>
                        <telerikCharting:ItemMapping FieldName="Population"
                                      DataPointMember="YValue" />
                        <telerikCharting:ItemMapping FieldName="Time"
                                      DataPointMember="XValue" />
                    </telerikCharting:SeriesMapping.ItemMappings>
                </telerikCharting:SeriesMapping>
            </telerikChart:RadChart.SeriesMappings>
        </telerikChart:RadChart>
    </Grid>
</Window>

Code Behind:

using System.Text;
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.Navigation;
using System.Windows.Shapes;

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

private void ToggleLogModeCheckBox_Checked(object sender, RoutedEventArgs e)
{
  if (this.RadChart1 != null)
  RadChart1.DefaultView.ChartArea.AxisY.IsLogarithmic = (bool)((CheckBox)sender).IsChecked;
}

}
}

View Model

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ComponentModel;

namespace Telerik.Windows.Examples.Chart.LogarithmicScale
{
    public class ExampleViewModel : ViewModelBase
    {
        private List<List<Stats>> data;
        public List<List<Stats>> Data
        {
            get
            {
                return this.data;
            }
            set
            {
                if (this.data != value)
                {
                    this.data = value;
                    this.NotifyPropertyChanged("Data");
                }
            }
        }

        public ExampleViewModel()
        {
            List<Stats> list0 = new List<Stats>();
            List<Stats> list1 = new List<Stats>();
            List<List<Stats>> listindex = new List<List<Stats>>();

            for (int i = 0; i <= 1000; i++)
                list0.Add(new Stats(i, 1 * i));

            for (int i = 0; i <= 1000; i++)
                list1.Add(new Stats(i, i * 10));

            listindex.Add(list0);
            listindex.Add(list1);

            this.Data = listindex;
        }
    }

    public class ViewModelBase : INotifyPropertyChanged, INotifyPropertyChanging
    {
        public event PropertyChangedEventHandler PropertyChanged;
        public event PropertyChangingEventHandler PropertyChanging;

        protected void NotifyPropertyChanged(String info)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(info));
            }
        }

        protected void NotifyPropertyChanging(String info)
        {
            if (PropertyChanging != null)
            {
                PropertyChanging(this, new PropertyChangingEventArgs(info));
            }
        }
    }
}

Model:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Telerik.Windows.Examples.Chart.LogarithmicScale
{
    public class Stats
    {
        private int _time;
        public int Time
        {
            get
            {
                return this._time;
            }
            set
            {
                this._time = value;
            }
        }

        private int _population;
        public int Population
        {
            get
            {
                return this._population;
            }
            set
            {
                this._population = value;
            }
        }

        public Stats(int time, int population)
        {
            this.Time = time;
            this.Population = population;
        }
    }
}

[Nikolay]

Hello Taylor,

We have been able to reproduce the issue locally and indeed the pointmarks do not update their positions correctly until the layout is updated as well ( resizing the window fixes the issue ). It has been logged for our developers to investigate further and provide a fix for one of the upcoming Latest Internal Builds, released each Monday.

Thank you for the feedback, your Telerik points have been updated.

All the best,
Nikolay
the Telerik team

[Asutosh]

hi 
i am using following code to set logarithm in my radhtml chart but TYPE property for Yaxis in not valid showing there how to set that
<telerik:RadHtmlChart ID="RadHtmlChart1" runat="server" Width="800px" Height="400px">
    <PlotArea>
        <YAxis Type="Log" Step="10"></YAxis>
        <Series>
            <telerik:ColumnSeries>
                <LabelsAppearance Visible="false"></LabelsAppearance>
            </telerik:ColumnSeries>
        </Series>
    </PlotArea>
    <ChartTitle Text="Fibonacci Sequence"></ChartTitle>
</telerik:RadHtmlChart>
and also i have attached 1 image i want bar for .01 and .05 value
how can i get it

[Pavel R. Pavlov]

Hello Asutosh,

You have actually reached the RadChart control for WPF. Please post your question in our UI ASPNET-AJAX forum.

Regards,
Pavel R. Pavlov
Telerik