feat!: automatic bin number calculation for variable registry

[CSantos01]

Added the automatic bin number calculation for variable registry as suggested by the eponymous issue and updated the docs+examples.

The function work similarly to update_variable_registry_ranges and is called update_variable_registry_binning.

Attached are the comparisons between the previous default binning (50) and the automatic binning using numpy.histogram_bin_edges with option "auto" for the bins variable.

Test auto-binning with 100k events:

Test_binnings_variable_0.pdf

Test auto-binning with 1k event:

Test_binnings_variable_0_1k.pdf

[Copilot]

Pull Request Overview

This PR adds automatic bin number calculation functionality to the variable registry system. It introduces the update_variable_registry_binning function that calculates optimal bin numbers using numpy's "auto" binning algorithm instead of the default 50 bins.

• Implements update_variable_registry_binning function using numpy's histogram_bin_edges with "auto" option
• Updates documentation and examples to demonstrate the new binning functionality
• Adds comprehensive test coverage for the new function including error cases and edge conditions

Reviewed Changes

Copilot reviewed 5 out of 8 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/plothist/variable_registry.py	Adds the core update_variable_registry_binning function implementation
src/plothist/init.py	Exports the new function in the public API
tests/test_variable_registry.py	Comprehensive test suite for the new binning functionality
docs/basics/variable_registry.rst	Documentation updates explaining the new binning feature
src/plothist/examples/2d_hist/2d_hist_correlations.py	Example usage of the new binning function

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[0ctagon]

Thank you for this contribution!

[CSantos01]

After discussion with @0ctagon and based on his comments, we decided to merge both update_variable_registry_ranges and update_variable_registry_binning into one, namely update_variable_registry_binning.

[Copilot]

Pull Request Overview

Copilot reviewed 5 out of 8 changed files in this pull request and generated 3 comments.

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[cyrraz]

Thank you for the PR! I left a comment.

[Copilot]

Pull Request Overview

Copilot reviewed 5 out of 8 changed files in this pull request and generated 2 comments.

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[cyrraz]

Looks good to me. Please check my new comment.

[0ctagon]

See the small comment. PR is good for me to be merged. Don't forget to add ! in the name of the squashed commit ;)