implement count_nested

[dougbrn]

Change Description

• My PR includes a link to the issue that I am addressing
  Resolves MVP: Implement the calc_nobs utility function #13

Solution Description

This PR implements the count_nested utility function, which is a generalization of the original calc_nobs idea.

Code Quality

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• My code follows the code style of this project
• My code builds (or compiles) cleanly without any errors or warnings
• My code contains relevant comments and necessary documentation

Project-Specific Pull Request Checklists

Bug Fix Checklist

• My fix includes a new test that breaks as a result of the bug (if possible)
• My change includes a breaking change
  • My change includes backwards compatibility and deprecation warnings (if possible)

New Feature Checklist

• I have added or updated the docstrings associated with my feature using the NumPy docstring format
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• I have added unit/End-to-End (E2E) test cases to cover my new feature
• My change includes a breaking change
  • My change includes backwards compatibility and deprecation warnings (if possible)

Documentation Change Checklist

• Any updated docstrings use the NumPy docstring format

Build/CI Change Checklist

• If required or optional dependencies have changed (including version numbers), I have updated the README to reflect this
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Other Change Checklist

• Any new or updated docstrings use the NumPy docstring format.
• I have updated the tutorial to highlight my new feature (if appropriate)
• I have added unit/End-to-End (E2E) test cases to cover any changes
• My change includes a breaking change
  • My change includes backwards compatibility and deprecation warnings (if possible)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 95.03%. Comparing base (d63cee9) to head (c073b2e).

❗ Current head c073b2e differs from pull request most recent head 48c83de. Consider uploading reports for the commit 48c83de to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #28      +/-   ##
==========================================
+ Coverage   94.92%   95.03%   +0.10%     
==========================================
  Files          13       15       +2     
  Lines         611      624      +13     
==========================================
+ Hits          580      593      +13     
  Misses         31       31              

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[github-actions]

Before [d63cee9]	After [55074fe]	Ratio	Benchmark (Parameter)
2.60±0.9s	1.41±0.8s	~0.54	benchmarks.time_computation
1.85k	3.45k	1.87	benchmarks.mem_list

Click here to view all benchmarks.

[hombit]

Beautiful!