ML.NET 1.5.0-preview

New Features (IN-PREVIEW, please provide feedback)

• Export-to-ONNX for below components:

  • WordTokenizingTransformer (#4451)
  • NgramExtractingTransformer (#4451)
  • OptionalColumnTransform (#4454)
  • KeyToValueMappingTransformer (#4455)
  • LbfgsMaximumEntropyMulticlassTrainer (4462)
  • LightGbmMulticlassTrainer (4462)
  • LightGbmMulticlassTrainer with SoftMax (4462)
  • OneVersusAllTrainer (4462)
  • SdcaMaximumEntropyMulticlassTrainer (4462)
  • SdcaNonCalibratedMulticlassTrainer (4462)
  • CopyColumn Transform (#4486)
  • PriorTrainer (#4515)

• DateTime Transformer (#4521)

• Loader and Saver for SVMLight file format (#4190)

  Sample

• Expression transformer (#4548) The expression transformer takes the expression in the form of text using syntax of a simple expression language, and performs the operation defined in the expression on the input columns in each row of the data. The transformer supports having a vector input column, in which case it applies the expression to each slot of the vector independently. The expression language is extendable to user defined operations.

  Sample

Bug Fixes

• Fix using permutation feature importance with Binary Prediction Transformer and CalibratedModelParametersBase loaded from disk. (#4306)
• Fixed model saving and loading of OneVersusAllTrainer to include SoftMax. (#4472)
• Ignore hidden columns in AutoML schema checks of validation data. (#4490)
• Ensure BufferBlocks are completed and empty in RowShufflingTransformer. (#4479)
• Create methods not being called when loading models from disk. (#4485)
• Fixes onnx exports for binary classification trainers. (#4463)
• Make PredictionEnginePool.GetPredictionEngine thread safe. (#4570)
• Memory leak when using FeaturizeText transform. (#4576)
• System.ArgumentOutOfRangeException issue in CustomStopWordsRemovingTransformer. (#4592)
• Image Classification low accuracy on EuroSAT Dataset. (4522)

Stability fixes by Sam Harwell

• Prevent exceptions from escaping FileSystemWatcher events. (#4535)
• Make local functions static where applicable. (#4530)
• Disable CS0649 in OnnxConversionTest. (#4531)
• Make test methods public. (#4532)
• Conditionally compile helper code. (#4534)
• Avoid running API Compat for design time builds. (#4529)
• Pass by reference when null is not expected. (#4546)
• Add Xunit.Combinatorial for test projects. (#4545)
• Use Theory to break up tests in OnnxConversionTest. (#4533)
• Update code coverage integration. (#4543)
• Use std::unique_ptr for objects in LdaEngine. (#4547)
• Enable VSTestBlame to show details for crashes. (#4537)
• Use std::unique_ptr for samplers_ and likelihood_in_iter_. (#4551)
• Add tests for IParameterValue implementations. (#4549)
• Convert LdaEngine to a SafeHandle. (#4538)
• Create SafeBoosterHandle and SafeDataSetHandle. (#4539)
• Add IterationDataAttribute. (#4561)
• Add tests for ParameterSet equality. (#4550)
• Add a test handler for AppDomain.UnhandledException. (#4557)

Breaking Changes

None

Enhancements

• Hash Transform API that takes in advanced options. (#4443)
• Image classification performance improvements and option to create validation set from train set. (#4522)
• Upgraded OnnxRuntime to v1.0 and Google Protobuf to 3.10.1. (#4416)

CLI and AutoML API

• None.

Remarks

• Thank you, Sam Harwell for making a series of stability fixes that has substantially increased the stability of our Build CI.