Add KLDivergence Metric

[hassiahk]

Before submitting

• Was this discussed/approved via a Github issue? (no need for typos and docs improvements)
• Did you read the contributor guideline, Pull Request section?
• Did you make sure to update the docs?
• Did you write any new necessary tests?

What does this PR do?

Fixes #66.

PR review

Anyone in the community is free to review the PR tationonce the tests have passed.
If we didn't discuss your PR in Github issues there's a high chance it will not be merged.

Did you have fun?

Make sure you had fun coding 🙃

Things to do

This is just for my reference.

• Minimal implementation
• Add class interface
• Add bindings to __init__ files
• Add tests
• Add documentation

[codecov]

Codecov Report

Merging #247 (22145aa) into master (4fc3a7a) will decrease coverage by 0.13%.
The diff coverage is 88.88%.

@@            Coverage Diff             @@
##           master     #247      +/-   ##
==========================================
- Coverage   96.64%   96.50%   -0.14%     
==========================================
  Files         107      109       +2     
  Lines        3428     3491      +63     
==========================================
+ Hits         3313     3369      +56     
- Misses        115      122       +7     

Flag	Coverage Δ
Linux	75.52% <58.73%> (-0.31%)	⬇️
Windows	75.52% <58.73%> (-0.31%)	⬇️
cpu	96.44% <88.88%> (-0.14%)	⬇️
gpu	96.41% <88.88%> (-0.14%)	⬇️
macOS	96.44% <88.88%> (-0.14%)	⬇️
pytest	96.50% <88.88%> (-0.14%)	⬇️
python3.6	95.55% <88.88%> (-0.13%)	⬇️
python3.8	96.44% <88.88%> (-0.14%)	⬇️
python3.9	96.36% <88.88%> (-0.14%)	⬇️
torch1.3.1	95.55% <88.88%> (-0.13%)	⬇️
torch1.4.0	95.64% <88.88%> (-0.13%)	⬇️
torch1.9.0	96.36% <88.88%> (-0.14%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
torchmetrics/__init__.py	100.00% <ø> (ø)
torchmetrics/classification/kldivergence.py	87.50% <87.50%> (ø)
...hmetrics/functional/classification/kldivergence.py	89.28% <89.28%> (ø)
torchmetrics/classification/__init__.py	100.00% <100.00%> (ø)
torchmetrics/functional/__init__.py	100.00% <100.00%> (ø)
torchmetrics/functional/classification/__init__.py	100.00% <100.00%> (ø)

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[SkafteNicki]

Overall looks like a great start but still needs some more work :]

• Add class interface
• Add test
• Add bindings to __init__ files
• Add documentation

[Borda]

@hassiahk how is it going here, still a draft or ready for full review?

[hassiahk]

@Borda, it's been a busy last month for me. I need to add documentation, tests etc, once I am done I will make the PR available for full review. Thanks!!

[Borda]

it's been a busy last month for me. I need to add documentation, tests etc, once I am done I will make the PR available for full review. Thanks!!

that would be great to have it landed :]

[Borda]

@hassiahk we are aiming at release by end of this week, do you think we can get this land by that time?

[hassiahk]

@Borda, really finding it hard to have time and work on this. I will try to complete but can't guarantee yet.

[pep8speaks]

Hello @hassiahk! Thanks for updating this PR.

There are currently no PEP 8 issues detected in this Pull Request. Cheers! 🍻

Comment last updated at 2021-06-28 09:59:45 UTC

[SkafteNicki]

Hi @hassiahk,
I took the time to complete the PR with the remaining changes.
Thanks again for wanting to contribute :]

[hassiahk]

I am really sorry for that @SkafteNicki. I was planning to do it today but thank you so much :)

[SkafteNicki]

Do not be sorry, just trying to get some of the PRs done before next release.
If you still want to contribute, I can see that you also asked to be assigned #73 :]

[Borda]

seems that Linux and Windows tests are hanging...

[SkafteNicki]

@Borda should be good now :]