Add doc for TBPTT

[chualanagit]

What does this PR do?

Fixes #19985

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---

📚 Documentation preview 📚: https://pytorch-lightning--20422.org.readthedocs.build/en/20422/

[lantiga]

Thank you for the contribution! I'd recommend moving this section to an How to guide, see comment.

[lantiga]

Looks great thank you!

A last request: can you add code that readers can just copy and run, after the explanation example? That is, add a snippet with the same code, but with:

• an actual simple RNN (something like https://github.com/Lightning-AI/pytorch-lightning/blob/master/tests/tests_pytorch/helpers/advanced_models.py#L165)
• the call to Trainer
• the __name__ == "__main__" section

This will make it easier for readers to just have a working example in front of them in a second by just copy-pasting.

Thanks again!

[lantiga]

Thank you! Almost there :-)

[lantiga]

Good to go, thank you @chualanagit!

[lantiga]

This will need to be added to the main index but I can do it after this is merged

[chualanagit]

This will need to be added to the main index but I can do it after this is merged

thank you!

[chualanagit]

@lantiga can you explain the doc-make errors, these seem to be blocking the merge. I can't seem to figure out what's cause them to fail.

[lantiga]

hey @chualanagit really sorry for the wait on this

we're super close, you got two warnings

First warning

/home/runner/work/pytorch-lightning/pytorch-lightning/docs/source-pytorch/common/tbptt.rst:1: WARNING: Title overline too short.

just change

##############
Truncated Backpropagation Through Time (TBPTT)
##############

to

##############################################
Truncated Backpropagation Through Time (TBPTT)
##############################################

Second warning

/home/runner/work/pytorch-lightning/pytorch-lightning/docs/source-pytorch/common/tbptt.rst: WARNING: document isn't included in any toctree

just add

.. displayitem::
    :header: Truncated Back-Propagation Through Time
    :description: Efficiently step through time when training recurrent models
    :button_link: ../common/tbtt.html
    :col_css: col-md-4
    :height: 180

to https://github.com/Lightning-AI/pytorch-lightning/blob/master/docs/source-pytorch/common/index.rst

[lantiga]

@chualanagit if you give me write access to your fork I can make these changes and get them in

[chualanagit]

hey @chualanagit really sorry for the wait on this

we're super close, you got two warnings

First warning

/home/runner/work/pytorch-lightning/pytorch-lightning/docs/source-pytorch/common/tbptt.rst:1: WARNING: Title overline too short.

just change

##############
Truncated Backpropagation Through Time (TBPTT)
##############

to

##############################################
Truncated Backpropagation Through Time (TBPTT)
##############################################

Second warning

/home/runner/work/pytorch-lightning/pytorch-lightning/docs/source-pytorch/common/tbptt.rst: WARNING: document isn't included in any toctree

just add

.. displayitem::
    :header: Truncated Back-Propagation Through Time
    :description: Efficiently step through time when training recurrent models
    :button_link: ../common/tbtt.html
    :col_css: col-md-4
    :height: 180

to https://github.com/Lightning-AI/pytorch-lightning/blob/master/docs/source-pytorch/common/index.rst

I'll make the change now, one second!

[chualanagit]

@lantiga fixed and added you as collaborator as well