/// <summary>
/// Save a transformer model and the loader used to create its input data to the stream.
/// </summary>
/// <param name="model">The trained model to be saved. Note that this can be <see langword="null"/>, as a shorthand
/// for an empty transformer chain. Upon loading with <see cref="LoadWithDataLoader(Stream, out IDataLoader{IMultiStreamSource})"/>
/// the returned value will be an empty <see cref="TransformerChain{TLastTransformer}"/>.</param>
/// <param name="loader">The loader that was used to create data to train the model.</param>
/// <param name="stream">A writeable, seekable stream to save to.</param>
public void Save <TSource>(ITransformer model, IDataLoader <TSource> loader, Stream stream)
{
_env.CheckValue(loader, nameof(loader));
_env.CheckValueOrNull(model);
_env.CheckValue(stream, nameof(stream));
// For the sake of consistency of this API specifically, when called upon we save any transformer
// in a single element transformer chain.
var chainedModel = model == null ? null : new TransformerChain <ITransformer>(model);
var compositeLoader = new CompositeDataLoader <TSource, ITransformer>(loader, chainedModel);
using (var rep = RepositoryWriter.CreateNew(stream))
{
ModelSaveContext.SaveModel(rep, compositeLoader, null);
rep.Commit();
}
}
private void SaveInputSchema(DataViewSchema inputSchema, RepositoryWriter rep)
{
_env.AssertValueOrNull(inputSchema);
_env.AssertValue(rep);
if (inputSchema == null)
{
return;
}
using (var ch = _env.Start("Saving Schema"))
{
var entry = rep.CreateEntry(SchemaEntryName);
var saver = new BinarySaver(_env, new BinarySaver.Arguments {
Silent = true
});
DataSaverUtils.SaveDataView(ch, saver, new EmptyDataView(_env, inputSchema), entry.Stream, keepHidden: true);
}
}
