public void LambdaTransformCreate()
{
using (var env = new ConsoleEnvironment(42))
{
var data = ReadBreastCancerExamples();
var idv = env.CreateDataView(data);
var map = LambdaTransform.CreateMap <BreastCancerExample, LambdaOutput>(env, idv,
(input, output) =>
{
output.OutField = string.Join(";", input.Features);
});
var filter = LambdaTransform.CreateFilter <BreastCancerExample, object>(env, map,
(input, state) => input.Label == 0, null);
Assert.Null(filter.GetRowCount(false));
// test re-apply
var applied = env.CreateDataView(data);
applied = ApplyTransformUtils.ApplyAllTransformsToData(env, filter, applied);
var saver = new TextSaver(env, new TextSaver.Arguments());
Assert.True(applied.Schema.TryGetColumnIndex("Label", out int label));
Assert.True(applied.Schema.TryGetColumnIndex("OutField", out int outField));
using (var fs = File.Create(GetOutputPath(OutputRelativePath, "lambda-output.tsv")))
saver.SaveData(fs, applied, label, outField);
}
}
public void CursorChannelExposedInMapTransform()
{
using (var env = new ConsoleEnvironment(0))
{
// Correct use of CursorChannel attribute.
var data1 = Utils.CreateArray(10, new OneIChannelWithAttribute());
var idv1 = env.CreateDataView(data1);
Assert.Null(data1[0].Channel);
var filter1 = LambdaTransform.CreateFilter <OneIChannelWithAttribute, object>(env, idv1,
(input, state) =>
{
Assert.NotNull(input.Channel);
return(false);
}, null);
filter1.GetRowCursor(col => true).MoveNext();
// Error case: non-IChannel field marked with attribute.
var data2 = Utils.CreateArray(10, new OneStringWithAttribute());
var idv2 = env.CreateDataView(data2);
Assert.Null(data2[0].Channel);
var filter2 = LambdaTransform.CreateFilter <OneStringWithAttribute, object>(env, idv2,
(input, state) =>
{
Assert.Null(input.Channel);
return(false);
}, null);
try
{
filter2.GetRowCursor(col => true).MoveNext();
Assert.True(false, "Throw an error if attribute is applied to a field that is not an IChannel.");
}
catch (InvalidOperationException ex)
{
Assert.True(ex.IsMarked());
}
// Error case: multiple fields marked with attributes.
var data3 = Utils.CreateArray(10, new TwoIChannelsWithAttributes());
var idv3 = env.CreateDataView(data3);
Assert.Null(data3[0].ChannelOne);
Assert.Null(data3[2].ChannelTwo);
var filter3 = LambdaTransform.CreateFilter <TwoIChannelsWithAttributes, object>(env, idv3,
(input, state) =>
{
Assert.Null(input.ChannelOne);
Assert.Null(input.ChannelTwo);
return(false);
}, null);
try
{
filter3.GetRowCursor(col => true).MoveNext();
Assert.True(false, "Throw an error if attribute is applied to a field that is not an IChannel.");
}
catch (InvalidOperationException ex)
{
Assert.True(ex.IsMarked());
}
// Correct case: non-marked IChannel field is not touched.
var example4 = new TwoIChannelsOnlyOneWithAttribute();
Assert.Null(example4.ChannelTwo);
Assert.Null(example4.ChannelOne);
var idv4 = env.CreateDataView(Utils.CreateArray(10, example4));
var filter4 = LambdaTransform.CreateFilter <TwoIChannelsOnlyOneWithAttribute, object>(env, idv4,
(input, state) =>
{
Assert.Null(input.ChannelOne);
Assert.NotNull(input.ChannelTwo);
return(false);
}, null);
filter1.GetRowCursor(col => true).MoveNext();
}
}