/// <summary>
/// Create a a map transform that is savable iff <paramref name="saveAction"/> and <paramref name="loadFunc"/> are
/// not null.
/// </summary>
/// <param name="env">The host environment</param>
/// <param name="source">The dataview upon which we construct the transform</param>
/// <param name="mapAction">The action by which we map source to destination columns</param>
/// <param name="saveAction">An action that allows us to save state to the serialization stream. May be
/// null simultaneously with <paramref name="loadFunc"/>.</param>
/// <param name="loadFunc">A function that given the serialization stream and a data view, returns
/// an <see cref="ITransformTemplate"/>. The intent is, this returned object should itself be a
/// <see cref="MapTransform{TSrc,TDst}"/>, but this is not strictly necessary. This delegate should be
/// a static non-lambda method that this assembly can legally call. May be null simultaneously with
/// <paramref name="saveAction"/>.</param>
/// <param name="inputSchemaDefinition">The schema definition overrides for <typeparamref name="TSrc"/></param>
/// <param name="outputSchemaDefinition">The schema definition overrides for <typeparamref name="TDst"/></param>
public MapTransform(IHostEnvironment env, IDataView source, Action <TSrc, TDst> mapAction,
Action <BinaryWriter> saveAction, LambdaTransform.LoadDelegate loadFunc,
SchemaDefinition inputSchemaDefinition = null, SchemaDefinition outputSchemaDefinition = null)
: base(env, RegistrationName, saveAction, loadFunc)
{
Host.AssertValue(source, "source");
Host.AssertValue(mapAction, "mapAction");
Host.AssertValueOrNull(inputSchemaDefinition);
Host.AssertValueOrNull(outputSchemaDefinition);
_source = source;
_mapAction = mapAction;
_inputSchemaDefinition = inputSchemaDefinition;
_typedSource = TypedCursorable <TSrc> .Create(Host, Source, false, inputSchemaDefinition);
var outSchema = outputSchemaDefinition == null
? InternalSchemaDefinition.Create(typeof(TDst), SchemaDefinition.Direction.Write)
: InternalSchemaDefinition.Create(typeof(TDst), outputSchemaDefinition);
_schema = MergedSchema.Create(_source.Schema, outSchema);
}
/// <summary>
/// Create a filter transform that is savable iff <paramref name="saveAction"/> and <paramref name="loadFunc"/> are
/// not null.
/// </summary>
/// <param name="env">The host environment</param>
/// <param name="source">The dataview upon which we construct the transform</param>
/// <param name="filterFunc">The function by which we transform source to destination columns and decide whether
/// to keep the row.</param>
/// <param name="initStateAction">The function that is called once per cursor to initialize state. Can be null.</param>
/// <param name="saveAction">An action that allows us to save state to the serialization stream. May be
/// null simultaneously with <paramref name="loadFunc"/>.</param>
/// <param name="loadFunc">A function that given the serialization stream and a data view, returns
/// an <see cref="ITransformTemplate"/>. The intent is, this returned object should itself be a
/// <see cref="MapTransform{TSrc,TDst}"/>, but this is not strictly necessary. This delegate should be
/// a static non-lambda method that this assembly can legally call. May be null simultaneously with
/// <paramref name="saveAction"/>.</param>
/// <param name="inputSchemaDefinition">The schema definition overrides for <typeparamref name="TSrc"/></param>
/// <param name="outputSchemaDefinition">The schema definition overrides for <typeparamref name="TDst"/></param>
public StatefulFilterTransform(IHostEnvironment env, IDataView source, Func <TSrc, TDst, TState, bool> filterFunc,
Action <TState> initStateAction,
Action <BinaryWriter> saveAction, LambdaTransform.LoadDelegate loadFunc,
SchemaDefinition inputSchemaDefinition = null, SchemaDefinition outputSchemaDefinition = null)
: base(env, RegistrationName, saveAction, loadFunc)
{
Host.AssertValue(source, "source");
Host.AssertValue(filterFunc, "filterFunc");
Host.AssertValueOrNull(initStateAction);
Host.AssertValueOrNull(inputSchemaDefinition);
Host.AssertValueOrNull(outputSchemaDefinition);
_source = source;
_filterFunc = filterFunc;
_initStateAction = initStateAction;
_inputSchemaDefinition = inputSchemaDefinition;
_typedSource = TypedCursorable <TSrc> .Create(Host, Source, false, inputSchemaDefinition);
var outSchema = InternalSchemaDefinition.Create(typeof(TDst), outputSchemaDefinition);
_schema = MergedSchema.Create(_source.Schema, outSchema);
}
/// <summary>
/// Create a a map transform that is savable iff <paramref name="saveAction"/> and <paramref name="loadFunc"/> are
/// not null.
/// </summary>
/// <param name="env">The host environment</param>
/// <param name="source">The dataview upon which we construct the transform</param>
/// <param name="mapAction">The action by which we map source to destination columns</param>
/// <param name="saveAction">An action that allows us to save state to the serialization stream. May be
/// null simultaneously with <paramref name="loadFunc"/>.</param>
/// <param name="loadFunc">A function that given the serialization stream and a data view, returns
/// an <see cref="ITransformTemplate"/>. The intent is, this returned object should itself be a
/// <see cref="MapTransform{TSrc,TDst}"/>, but this is not strictly necessary. This delegate should be
/// a static non-lambda method that this assembly can legally call. May be null simultaneously with
/// <paramref name="saveAction"/>.</param>
/// <param name="inputSchemaDefinition">The schema definition overrides for <typeparamref name="TSrc"/></param>
/// <param name="outputSchemaDefinition">The schema definition overrides for <typeparamref name="TDst"/></param>
public MapTransform(IHostEnvironment env, IDataView source, Action <TSrc, TDst> mapAction,
Action <BinaryWriter> saveAction, LambdaTransform.LoadDelegate loadFunc,
SchemaDefinition inputSchemaDefinition = null, SchemaDefinition outputSchemaDefinition = null)
: base(env, RegistrationName, saveAction, loadFunc)
{
Host.AssertValue(source);
Host.AssertValue(mapAction);
Host.AssertValueOrNull(inputSchemaDefinition);
Host.AssertValueOrNull(outputSchemaDefinition);
Source = source;
_mapAction = mapAction;
_inputSchemaDefinition = inputSchemaDefinition;
_typedSource = TypedCursorable <TSrc> .Create(Host, Source, false, inputSchemaDefinition);
var outSchema = outputSchemaDefinition == null
? InternalSchemaDefinition.Create(typeof(TDst), SchemaDefinition.Direction.Write)
: InternalSchemaDefinition.Create(typeof(TDst), outputSchemaDefinition);
_addedSchema = outSchema;
_bindings = new ColumnBindings(Data.Schema.Create(Source.Schema), DataViewConstructionUtils.GetSchemaColumns(outSchema));
}