# LogarithmicConverter Class

> The class WPF.LogarithmicConverter converts a numeric value from a linear scale to a logarithmic scale. It can be used to provide better usability when mapping a zoom factor to a slider, for example. The range of values of the linear as well as the logarithmic scale have to be defined with the given "Minimum"- and "Maximum"-properties. Provides a possibility to define an input value which should be mapped to the center of the output range of values. The class can be used in XAML as a static resource to automatically convert bound property values.

- **Product:** TX Text Control .NET for WPF
- **Section:** Reference
- **Kind:** Class
- **Introduced:** 16.0
- **Namespace:** `TXTextControl.WPF`
- **Package:** `TXTextControl.TextControl.WPF.SDK` (assembly `TXTextControl.WPF.dll`, from the private NuGet feed or Text Control Offline Packages)
- **.NET Framework:** reference `TXTextControl.WPF.dll` from the setup
- **Implements:** `System.Windows.Data.IValueConverter`
- **Path:** TX Text Control .NET for WPF > Reference > TXTextControl.WPF > LogarithmicConverter Class
- **1076 words**
- **Web URL:** https://docs.textcontrol.com/tx-text-control-dotnet-wpf/reference/txtextcontrol-wpf/logarithmicconverter/
- **LLMs URL:** https://docs.textcontrol.com/tx-text-control-dotnet-wpf/reference/txtextcontrol-wpf/logarithmicconverter/llms.txt
- **LLMs-Full URL:** https://docs.textcontrol.com/tx-text-control-dotnet-wpf/reference/txtextcontrol-wpf/logarithmicconverter/llms-full.txt

---

### Description

The class WPF.LogarithmicConverter converts a numeric value from a linear scale to a logarithmic scale. It can be used to provide better usability when mapping a zoom factor to a slider, for example. The range of values of the linear as well as the logarithmic scale have to be defined with the given "Minimum"- and "Maximum"-properties. Provides a possibility to define an input value which should be mapped to the center of the output range of values. The class can be used in XAML as a static resource to automatically convert bound property values.

### Syntax

```csharp
public class LogarithmicConverter : IValueConverter
```

```vbnet
Public Class LogarithmicConverter
    Implements IValueConverter
```

### Examples

The following XAML example shows how to bind the [TextControl.ZoomFactor](https://docs.textcontrol.com/tx-text-control-dotnet-wpf/reference/txtextcontrol-wpf/textcontrol/zoomfactor-property/llms-full.txt) property to a slider using the LogarithmicConverter mapping a zoom range from 10 to 400 percent to a value range from 0 to 100.

```plaintext
…
xmlns:tx="clr-namespace:TXTextControl.WPF;assembly=TXTextControl.WPF"
…
<Window.Resources>
    <tx:LogarithmicConverter
        x:Key="logConv"
        InputMinimum="10"
        InputCenter="100"
        InputMaximum="400"
        OutputMinimum="0"
        OutputMaximum="100" />
</Window.Resources>
…
<Slider
    Minimum="0"
    Maximum="100"
    Value="{Binding ElementName=textControl1, Path=ZoomFactor, Converter={StaticResource logConv}}" />
```

The following example creates a Logarithmic Converter instance and configures its input minimum setting for a document workflow.

```csharp
TXTextControl.WPF.LogarithmicConverter logarithmicConverter = new();
logarithmicConverter.InputMinimum = 1.0;
```

```vbnet
Dim logarithmicConverter As New TXTextControl.WPF.LogarithmicConverter()
logarithmicConverter.InputMinimum = 1.0
```

---

## In This Section

- [LogarithmicConverter.Convert Method](https://docs.textcontrol.com/tx-text-control-dotnet-wpf/reference/txtextcontrol-wpf/logarithmicconverter/convert-method/llms-full.txt): Converts an integer or a double precision floating point value to an integer or a double precision floating point value.
- [LogarithmicConverter.ConvertBack Method](https://docs.textcontrol.com/tx-text-control-dotnet-wpf/reference/txtextcontrol-wpf/logarithmicconverter/convertback-method/llms-full.txt): Converts an integer or a double precision floating point value to an integer or a double precision floating point value.
- [LogarithmicConverter.InputCenter Property](https://docs.textcontrol.com/tx-text-control-dotnet-wpf/reference/txtextcontrol-wpf/logarithmicconverter/inputcenter-property/llms-full.txt): Sets or gets the numeric value of the source value range which will be mapped to the center of the target value range.
- [LogarithmicConverter.InputMaximum Property](https://docs.textcontrol.com/tx-text-control-dotnet-wpf/reference/txtextcontrol-wpf/logarithmicconverter/inputmaximum-property/llms-full.txt): Sets or gets the upper bound of the source value range. Larger input values coming from the binding source are handled as if they were equal to this value.
- [LogarithmicConverter.InputMinimum Property](https://docs.textcontrol.com/tx-text-control-dotnet-wpf/reference/txtextcontrol-wpf/logarithmicconverter/inputminimum-property/llms-full.txt): Sets or gets the lower bound of the source value range. Smaller input values coming from the binding source are handled as if they were equal to this value.
- [LogarithmicConverter.OutputMaximum Property](https://docs.textcontrol.com/tx-text-control-dotnet-wpf/reference/txtextcontrol-wpf/logarithmicconverter/outputmaximum-property/llms-full.txt): Sets or gets the upper bound of the target value range. Larger values coming from the binding target are handled as if they were equal to this value.
- [LogarithmicConverter.OutputMinimum Property](https://docs.textcontrol.com/tx-text-control-dotnet-wpf/reference/txtextcontrol-wpf/logarithmicconverter/outputminimum-property/llms-full.txt): Sets or gets the lower bound of the target value range. Smaller values coming from the binding target are handled as if they were equal to this value.

---

## Nearby

- **Previous:** [HyperlinkDialog.DialogItem Enumeration](https://docs.textcontrol.com/tx-text-control-dotnet-wpf/reference/txtextcontrol-wpf/hyperlinkdialog/dialogitem-enumeration/llms-full.txt)
- **Next:** [LogarithmicConverter.Convert Method](https://docs.textcontrol.com/tx-text-control-dotnet-wpf/reference/txtextcontrol-wpf/logarithmicconverter/convert-method/llms-full.txt)