Description

Brief Description of the PR:

add a tutorial for CRF Layer

To Reviewers:

Here is the candidate feature list for this tutorial:

• [Done] Replace faked training data with real training data:
  • Pros: make the tutorial more practicable
  • Cons: Add many codes for data processing, make it longer and less concentration.
• [Done] Add additional custom training step base approach (co-exists with current custom training loop based approach):
  • Pros: User have more choose of programming style
  • Cons: Add some (not much) codes, make it longer and less concentration.

What do you think?

Fixes # (issue)

Type of change

• [ ] Bug fix
• [x] New Tutorial
• [ ] Updated or additional documentation
• [ ] Additional Testing
• [ ] New Activation and the changes conform to the activation contribution guidelines
• [ ] New Callback and the changes conform to the callback contribution guidelines
• [ ] New Image addition and the changes conform to the image op contribution guidelines
• [ ] New Layer and the changes conform to the layer contribution guidelines
• [ ] New Loss and the changes conform to the loss contribution guidelines
• [ ] New Metric and the changes conform to the metric contribution guidelines
• [ ] New Optimizer and the changes conform to the optimizer contribution guidelines
• [ ] New RNN Cell and the changes conform to the rnn contribution guidelines
• [ ] New Seq2seq addition and the changes conform to the seq2seq contribution guidelines
• [ ] New Text addition and the changes conform to the text op contribution guidelines

Checklist:

• [ ] I've properly formatted my code according to the guidelines
  • [ ] By running Black + Flake8
  • [ ] By running pre-commit hooks
• [ ] This PR addresses an already submitted issue for TensorFlow Addons
• [ ] I have made corresponding changes to the documentation
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] This PR contains modifications to C++ custom-ops

How Has This Been Tested?

If you're adding a bugfix or new feature please describe the tests that you ran to verify your changes: *

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Update: I am working on update this tutorial with real training data.

Update: all the planed features are implemented. it still needs some polish but it's ready for technical review.

When #2555 is merged, I will update this tutorial accrodingly.

@howl-anderson Can you join in the official forum?

We have some user looking for CRF support: https://discuss.tensorflow.org/t/how-to-implement-and-use-a-linear-chain-crf-in-tensorflow/4742/

@bhack Sure, I will handle this. Thank you!

Update: since #2555 is merged, I will update this tutorial soon.

Update: The tutorial is ready. Depends on #2591

@seanpmorgan Please take a look

@MarkDaoust Please take a look

Thank you for your contribution. We sincerely apologize for any delay in reviewing, but TensorFlow Addons is transitioning to a minimal maintenance and release mode. New features will not be added to this repository. For more information, please see our public messaging on this decision: TensorFlow Addons Wind Down

Please consider sending feature requests / contributions to other repositories in the TF community with a similar charters to TFA: Keras Keras-CV Keras-NLP