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# SFSpeechLanguageModel.Configuration

An object describing the location of a custom language model and specialized vocabulary.

```
class Configuration
```

## Overview

Pass this object to [`prepareCustomLanguageModel(for:configuration:completion:)`](/documentation/Speech/SFSpeechLanguageModel/prepareCustomLanguageModel(for:configuration:completion:)) to indicate where that method should create the custom language model file, and to [`customizedLanguageModel`](/documentation/Speech/SFSpeechRecognitionRequest/customizedLanguageModel) or [`customizedLanguage(modelConfiguration:)`](/documentation/Speech/DictationTranscriber/ContentHint/customizedLanguage(modelConfiguration:)) to indicate where the system should find that model to use.

## Topics

### Creating a language model configuration

[`init(languageModel:)`](/documentation/Speech/SFSpeechLanguageModel/Configuration/init(languageModel:))

Creates a configuration with the location of a language model file.

[`init(languageModel:vocabulary:)`](/documentation/Speech/SFSpeechLanguageModel/Configuration/init(languageModel:vocabulary:))

Creates a configuration with the locations of language model and vocabulary files.

[`init(languageModel:vocabulary:weight:)`](/documentation/Speech/SFSpeechLanguageModel/Configuration/init(languageModel:vocabulary:weight:))

Creates a configuration with the locations of language model and vocabulary files, and custom weight.

### Inspecting a language model

[`languageModel`](/documentation/Speech/SFSpeechLanguageModel/Configuration/languageModel)

The location of a compiled language model file.

[`vocabulary`](/documentation/Speech/SFSpeechLanguageModel/Configuration/vocabulary)

The location of a compiled vocabulary file.

[`weight`](/documentation/Speech/SFSpeechLanguageModel/Configuration/weight)

The relative weight of the language model customization. Value must be between 0.0 and 1.0 inclusive.


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