docs: add cdf_/ibnr_/pipe/set_backend examples (#704)

[EKtheSage]

Summary of Changes

• Add doctest Examples for cdf_, pct_reported_, ibnr_, and set_backend in chainladder/core/common.py.
• Convert the existing pipe example from >>> doctest style to testsetup / testcode / testoutput.
• Stop excluding cdf_ / ibnr_ / pct_reported_ from the class autosummary templates so the examples appear on estimator and Triangle API pages.

Related GitHub Issue(s)

• API Reference Examples #704

Additional Context for Reviewers

Bite-sized core-module follow-up for #704. Companions: #1208 (slice), #1209 (io), #1210 (display).

Checklist

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

Made with Cursor

[github-actions]

Pyright Type Completeness

View the full pyright --verifytypes output for this commit

Project (full chainladder package, at this PR's head): 14.9% of exported symbols fully typed (202 / 1356)

	Known	Ambiguous	Unknown	Total
Project (head)	202	111	1043	1356

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: 324
• Functions without default param: 0
• Classes without docstring: 10

Patch (exported symbols added or changed by this PR): 0.0% fully typed (0 / 1)

	Known	Ambiguous	Unknown	Total
Patch	0	0	1	1

Patch symbol details

Symbol	Status	Change
chainladder.core.tests.test_pattern_cum_to_incr.test_pattern_cum_to_incr_zero_cells_stay_finite	❌ unknown	new

[codecov]

Codecov Report

❌ Patch coverage is 92.85714% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 91.32%. Comparing base (bd0d539) to head (e4e141f).

Files with missing lines	Patch %	Lines
chainladder/core/triangle.py	91.30%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1212   +/-   ##
=======================================
  Coverage   91.31%   91.32%           
=======================================
  Files          91       92    +1     
  Lines        5434     5438    +4     
  Branches      700      700           
=======================================
+ Hits         4962     4966    +4     
  Misses        336      336           
  Partials      136      136           

Flag	Coverage Δ
unittests	91.32% <92.85%> (+<0.01%)	⬆️

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[henrydingliu]

for cdf_/ibnr_, i think we need to make them a part of a bigger refactor that make ldf_ and ultimate_ into properties. for now, i would recommend that we point the user from Triangle to the lists of attributes in Development and Chainladder, via a See Also.

pct_reported_ should be added to the attribute list in Development

good with the rest.

[EKtheSage]

cdf_ / ibnr_ are no longer un-excluded on the Triangle autosummary page. Triangle now has a See Also to Development (ldf_, cdf_) and Chainladder (ultimate_, ibnr_).

pct_reported_ is on the Development attribute list. The property examples stay on the estimator pages via class.rst.

[henrydingliu]

ruff fix pretty pls?

[kennethshsu]

@EKtheSage you may need to do a uv sync to get the ruff stuff in

[EKtheSage]

Ruff: the workflow clears per-file ignores on touched files, so triangle.py / common.py needed the actual E721/E731/E712/F401/F841 fixes rather than a uv sync. Those ignores are dropped.

The autosummary template is the same union as #1208/#1211/#1213 (indexers, shape attrs, arithmetic dunders). cdf_ / ibnr_ / pct_reported_ stay off the Triangle page.

[EKtheSage]

Merged main. The new E2 ruleset from #1204 is what CI ruff actually enforces on touched files (--config lint.per-file-ignores={}); uv sync does not change that. triangle.py / development.py are E2-clean and those ignores are dropped.

The failing Triangle pipe() doctest was pandas header padding. That example now uses NORMALIZE_WHITESPACE.

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[henrydingliu]

@EKtheSage thanks for all the work! FYI there's a cursor warning and a conflict

[EKtheSage]

The Cursor warning was a real side-effect of the F841 cleanup: num_to_value(self.values, 1) mutates zeros to ones before pattern cum_to_incr divides adjacent ages. That call is restored, with a regression test that a zero CDF cell stays finite.

Conflict: merged upstream/main into this branch (not into casact main).

[henrydingliu]

new test doesn't need to be its own file but harmless as is