Sparse fixture

[henrydingliu]

Summary of Changes

Related GitHub Issue(s)

Additional Context for Reviewers

• I passed tests locally for both code (uv run pytest) and documentation changes (uv run jb build docs --builder=custom --custom-builder=doctest)

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Note

Low Risk
Changes are limited to tests and inline comments; production logic is unchanged except a non-functional comment in Mack summary_.

Overview
Adds unit tests for chainladder.utils.sparse.nanquantile on 1D COO inputs and with keepdims=True, including imports of nanquantile and sparse.all.

Test hygiene only elsewhere: comments in test_grain, test_development, and mack.summary_ clarify default auto_sparse / backend alignment; test_auto_sparse_disabled_returns_self docstring now documents the prism_convert fixture (reduced prism for speed).

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[github-actions]

Pyright Type Completeness

View the full pyright --verifytypes output for this commit

Project (full chainladder package, at this PR's head): 15.1% of exported symbols fully typed (195 / 1294)

	Known	Ambiguous	Unknown	Total
Project (head)	195	110	989	1294

Other symbols referenced but not exported by chainladder: 13

	Known	Ambiguous	Unknown	Total
Other (head)	3	1	9	13

Symbols without documentation:

• Functions without docstring: 315
• Functions without default param: 0
• Classes without docstring: 10

Patch (exported symbols added or changed by this PR): 100.0% fully typed (2 / 2)

	Known	Ambiguous	Unknown	Total
Patch	2	0	0	2

Patch symbol details

Symbol	Status	Change
chainladder.utils.tests.test_sparse.test_1D_nanquantile	✅ known	new
chainladder.utils.tests.test_sparse.test_keepdims_nanquantile	✅ known	new

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[cursor]

Faulty nanquantile scalar assertion

Low Severity

nanquantile always returns a COO, so assert nanquantile(a, 0.5) == 2.5 checks truthiness of a boolean COO instead of a scalar. That can error or pass regardless of the value. Nearby checks correctly use sparse_all for COO equality.

 

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