[ENH] single join fully implemented in numba

[samukweku]

PR Description

Please describe the changes proposed in the pull request:

• implement single conditional join fully in numba (for less than and greater than conditions)
• not equal operator implemented with numpy (no numba implementation)

This PR resolves #1302 .

PR Checklist

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3. Add a line to CHANGELOG.md under the latest version header (i.e. the one that is "on deck") describing the contribution.
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Automatic checks

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• Building a preview of the docs on Netlify
• Automatically linting the code
• Making sure the code is documented
• Making sure that all tests are passed
• Making sure that code coverage doesn't go down.

Relevant Reviewers

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• @ericmjl

[ericmjl]

🚀 Deployed on https://deploy-preview-1304--pyjanitor.netlify.app

[codecov]

Codecov Report

Merging #1304 (8ed2462) into dev (04fa118) will increase coverage by 1.76%.
Report is 4 commits behind head on dev.
The diff coverage is 96.58%.

Additional details and impacted files

@@            Coverage Diff             @@
##              dev    #1304      +/-   ##
==========================================
+ Coverage   92.85%   94.61%   +1.76%     
==========================================
  Files          78       78              
  Lines        4142     4254     +112     
==========================================
+ Hits         3846     4025     +179     
+ Misses        296      229      -67     

[ericmjl]

Pre-approving pending docstrings!

[ericmjl]

@samukweku I took the liberty of asking ChatGPT for a better docstring on this test.

@pytest.mark.turtle
@settings(deadline=None, max_examples=10)
@given(df=conditional_df(), right=conditional_right())
def test_single_condition_greater_than_floats_keep_last_numba(df, right):
    """
    Test the functionality of conditional_join with a single 'greater than' condition on floating-point data, while keeping the last match using Numba.

    This test sorts and filters dataframes 'df' and 'right' by columns 'B' and 'Numeric' respectively, removing NaN values. It then performs a backward merge_asof operation on these sorted dataframes. The expected outcome is a dataframe where each row from 'df' is merged with the last row from 'right' where 'Numeric' is greater than 'B'.

    The actual outcome is produced by the conditional_join method with a 'greater than' condition, left join type, sorted by appearance, keeping the last match, and utilizing Numba for performance optimization. The test asserts that the actual dataframe matches the expected dataframe, ensuring correct functionality of the conditional_join under these specific parameters.
    """
    # Test implementation continues...

Is it accurate? If so, I might begin writing a template for testing! Also, if it is accurate, could you update the docstrings for these two tests please? (I will get them generated for the other one.)

[ericmjl]

@pytest.mark.turtle
@settings(deadline=None, max_examples=10)
@given(df=conditional_df(), right=conditional_right())
def test_single_condition_greater_than_floats_keep_last_numba(df, right):
    """
    Test the functionality of conditional_join with a single 'greater than' condition on floating-point data, while keeping the last match using Numba.

    This test sorts and filters dataframes 'df' and 'right' by columns 'B' and 'Numeric' respectively, removing NaN values. It then performs a backward merge_asof operation on these sorted dataframes. The expected outcome is a dataframe where each row from 'df' is merged with the last row from 'right' where 'Numeric' is greater than 'B'.

    The actual outcome is produced by the conditional_join method with a 'greater than' condition, left join type, sorted by appearance, keeping the last match, without utilizing Numba for performance optimization. The test asserts that the actual dataframe matches the expected dataframe, ensuring correct functionality of the conditional_join under these specific parameters.
    """
    # Test implementation continues...

[samukweku]

feels like a lot of docstring info for tests, no?

[ericmjl]

You have a good point, actually. I'm still a bit conflicted on whether to be verbose on test docstrings.

[ericmjl]

@samukweku are we good to merge? I think we should, please let me know.

[samukweku]

@ericmjl yes it is ok to merge

[ericmjl]

Thank you very much, @samukweku!