internal DataReaderEstimator(IHostEnvironment env, IDataReaderEstimator <TIn, TDataReader> estimator, StaticSchemaShape shape)
: base(env, shape)
{
Env.AssertValue(estimator);
AsDynamic = estimator;
Shape.Check(Env, AsDynamic.GetOutputSchema());
}
/// <summary>
/// Create a composite reader estimator by appending an estimator to a reader estimator.
/// </summary>
public static CompositeReaderEstimator <TSource, TTrans> Append <TSource, TTrans>(
this IDataReaderEstimator <TSource, IDataReader <TSource> > start, IEstimator <TTrans> estimator)
where TTrans : class, ITransformer
{
Contracts.CheckValue(start, nameof(start));
Contracts.CheckValue(estimator, nameof(estimator));
return(new CompositeReaderEstimator <TSource, ITransformer>(start).Append(estimator));
}
public CompositeReaderEstimator(IDataReaderEstimator <TSource, IDataReader <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 reader's schema.
// Right now it throws.
// GetOutputSchema();
}
public static DataReaderEstimator <TIn, T, TReader> AssertStatic <TIn, [IsShape] T, TReader>(
this IDataReaderEstimator <TIn, TReader> readerEstimator, IHostEnvironment env,
Func <SchemaAssertionContext, T> outputDecl)
where TReader : class, IDataReader <TIn>
{
Contracts.CheckValue(env, nameof(env));
env.CheckValue(readerEstimator, nameof(readerEstimator));
env.CheckValue(outputDecl, nameof(outputDecl));
var schema = StaticSchemaShape.Make <T>(outputDecl.Method.ReturnParameter);
return(new DataReaderEstimator <TIn, T, TReader>(env, readerEstimator, schema));
}
public static IDataView FitAndRead <TSource>(this IDataReaderEstimator <TSource, IDataReader <TSource> > est, TSource source) => est.Fit(source).Read(source);