Adds indexing operation to Metric class

[victorjoos]

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 #132 (issue).

PR review

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If we didn't discuss your PR in Github issues there's a high chance it will not be merged.

Did you have fun?

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[codecov]

Codecov Report

Merging #142 (407136e) into master (b7312a2) will decrease coverage by 0.02%.
The diff coverage is 55.55%.

@@            Coverage Diff             @@
##           master     #142      +/-   ##
==========================================
- Coverage   79.29%   79.26%   -0.03%     
==========================================
  Files          78       78              
  Lines        2405     2407       +2     
==========================================
+ Hits         1907     1908       +1     
- Misses        498      499       +1     

Flag	Coverage Δ
Linux	79.26% <55.55%> (-0.03%)	⬇️
Windows	79.26% <55.55%> (-0.03%)	⬇️
cpu	79.26% <55.55%> (-0.03%)	⬇️
macOS	79.26% <55.55%> (-0.03%)	⬇️
pytest	79.26% <55.55%> (-0.03%)	⬇️

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

Impacted Files	Coverage Δ
torchmetrics/metric.py	55.21% <50.00%> (-0.05%)	⬇️
torchmetrics/wrappers/bootstrapping.py	79.31% <66.66%> (ø)

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[pep8speaks]

Hello @victorjoos! Thanks for updating this PR.

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

Comment last updated at 2021-03-29 11:54:13 UTC