internal DataLoaderEstimator(IHostEnvironment env, IDataLoaderEstimator <TIn, TDataLoader> estimator, StaticSchemaShape shape)
: base(env, shape)
{
Env.AssertValue(estimator);
AsDynamic = estimator;
Shape.Check(Env, AsDynamic.GetOutputSchema());
}
/// <summary>
/// Create a new composite loader estimator, by appending another estimator to the end of this data loader estimator.
/// </summary>
public static CompositeLoaderEstimator <TSource, TTrans> Append <TSource, TTrans>(
this IDataLoaderEstimator <TSource, IDataLoader <TSource> > start, IEstimator <TTrans> estimator)
where TTrans : class, ITransformer
{
Contracts.CheckValue(start, nameof(start));
Contracts.CheckValue(estimator, nameof(estimator));
return(new CompositeLoaderEstimator <TSource, ITransformer>(start).Append(estimator));
}
public CompositeLoaderEstimator(IDataLoaderEstimator <TSource, IDataLoader <TSource> > start, EstimatorChain <TLastTransformer> estimatorChain = null)
{
Contracts.CheckValue(start, nameof(start));
Contracts.CheckValueOrNull(estimatorChain);
_start = start;
_estimatorChain = estimatorChain ?? new EstimatorChain <TLastTransformer>();
// REVIEW: enforce that estimator chain can read the loader's schema.
// Right now it throws.
// GetOutputSchema();
}
public static DataLoaderEstimator <TIn, T, TLoader> AssertStatic <TIn, [IsShape] T, TLoader>(
this IDataLoaderEstimator <TIn, TLoader> loaderEstimator, IHostEnvironment env,
Func <SchemaAssertionContext, T> outputDecl)
where TLoader : class, IDataLoader <TIn>
{
Contracts.CheckValue(env, nameof(env));
env.CheckValue(loaderEstimator, nameof(loaderEstimator));
env.CheckValue(outputDecl, nameof(outputDecl));
var schema = StaticSchemaShape.Make <T>(outputDecl.Method.ReturnParameter);
return(new DataLoaderEstimator <TIn, T, TLoader>(env, loaderEstimator, schema));
}