💡 Version 0.0.7

[Antonio-JP]

Pull request including new results from paper "Effective computation of centralizers of ODOs".

This new version concludes the computation of Centralizers for linear differential operators $L$ as a $C[L]$-module, it begins the computations of the Burchnall-Chaundy ideals and also the study of what is called in the paper "level varieties".
It includes also a new notebook to showcase the examples in the paper and a new experiment to generate and study families of operators with no-trivial centralizers.

This version also includes the "elliptic" extensions for differential fields: an element $\eta$ is d-elliptic over a differential field $F$ if it is transcendental over $F$ and its derivative ($\eta'$) is algebraic over $F(\eta)$.

[Copilot]

Pull Request Overview

This pull request adds new experimental results from the paper "Effective computation of centralizers of ODOs" and extends the framework to support elliptic extensions as well as advanced computations for Burchnall–Chaundy ideals and level varieties. Key changes include the addition of new result files (rows, report, matrix) for the elliptic cases and significant code refinements in several modules (logging, differential rings, differential polynomial systems, commutators) along with updated copyright headers and minor API adjustments.

Reviewed Changes

Copilot reviewed 165 out of 170 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
experiments/centralizers/results/*.md	New markdown result files with experimental outcome lists and detailed reports.
dalgebra/logging/logging.py	Refactored logging calls (switching from info to logger.log with custom level) and removed duplicate COUNTING_CALLS definition.
dalgebra/dpolynomial/dsystems.py	Modified variable existence check and enforced conversion to Sage polynomials using the as_sage flag.
dalgebra/commutators/ideals.py	Updated logging level usage (switching some info to debug) and adjusted the condition in repr for solution branches.
dalgebra/init.py	Enhanced version retrieval with proper exception handling.

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Files not reviewed (5)

• Makefile: Language not supported
• VERSION: Language not supported
• experiments/almost_commuting/manage_data.sage: Language not supported
• experiments/almost_commuting/script.sage: Language not supported
• experiments/centralizers/results/.gitignore: Language not supported

Comments suppressed due to low confidence (4)

dalgebra/logging/logging.py:31

• Good cleanup: the duplicate declaration of COUNTING_CALLS has been removed. Ensure that downstream code uses this centralized COUNTING_CALLS dictionary consistently.

COUNTING_CALLS : dict[str, int] = dict()

dalgebra/dpolynomial/dsystems.py:117

• The check for variables now explicitly requires a non-empty collection, which clarifies intent. Confirm this does not unexpectedly filter out valid falsy inputs.

if (variables is not None and len(variables) > 0):

dalgebra/dpolynomial/dsystems.py:559

• Forcing the conversion with 'as_sage=True' ensures uniform algebraic behavior; please verify this change aligns with the intended use in downstream computations.

equations = tuple(self.parent().as_polynomials(*self.equations(), as_sage=True))

dalgebra/commutators/ideals.py:361

• [nitpick] Note the change from an 'and' condition to an 'or' condition for printing relations in the SolutionBranch repr. Verify that including a single nonzero generator now is intentional.

if self.__I.ngens() > 1 or self.__I.gens()[0] != 0: