Propagate primal simplex to APIs. Ensure consistency with dual simplex.

[chris-maes]

Make sure primal simplex gets picked up in all the APIs.

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[chris-maes]

/ok to test 49b1fa5

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⛔ Files ignored due to path filters (3)

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📒 Files selected for processing (2)

• cpp/tests/linear_programming/unit_tests/pdlp_memory_test.cu
• python/cuopt/cuopt/linear_programming/solution/solution.py

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• python/cuopt/cuopt/linear_programming/solution/solution.py

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📝 Walkthrough

Walkthrough

The primal method is renamed to primal simplex across C++ and language bindings. The LP dispatcher selects the primal simplex branch, and result labels, method descriptions, parameter ranges, and tests are updated.

Changes

Primal Simplex Method

Layer / File(s)	Summary
C++ method contract and dispatch cpp/include/cuopt/mathematical_optimization/constants.h, cpp/include/cuopt/mathematical_optimization/pdlp/*, cpp/src/pdlp/solve.cu, cpp/src/math_optimization/solver_settings.cu, cpp/src/grpc/codegen/field_registry.yaml, cpp/src/dual_simplex/simplex_solver_settings.hpp, cpp/tests/linear_programming/unit_tests/pdlp_memory_test.cu	The method constant and enum identify primal simplex. The LP dispatcher routes the method to run_primal, and result conversion labels it PrimalSimplex. Parameter ranges and method descriptions include primal simplex. Related C++ comments describe the solver method and Devex default.
Language bindings and validation java/cuopt/src/main/java/com/nvidia/cuopt/mathematicaloptimization/SolverMethod.java, java/cuopt/src/test/java/com/nvidia/cuopt/mathematicaloptimization/ProblemModelingTest.java, python/cuopt/cuopt/linear_programming/solver_settings/*, python/cuopt/cuopt/linear_programming/solution/solution.py, python/cuopt_mcp/tests/test_schema.py, python/cuopt_self_hosted/cuopt_sh_client/thin_client_solver_settings.py, python/cuopt_self_hosted/tests/test_solver_settings.py	Java and Python expose PrimalSimplex. Tests check the native value or schema mapping. Python solution documentation describes solved_by as the method that solved the LP.

Priority: ⬇️ Low

Estimated code review effort: 2 (Simple) | ~12 minutes

Change: Feature

Suggested reviewers: mlubin, iroy30

Merge Risk: 🔵 Low · up to 75db6

Python clients still using SolverMethod.Primal will need to switch to PrimalSimplex. This is a bounded compatibility risk; merge with awareness that the rename breaks those callers.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 28.57% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 14 functions across 13 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main change: making primal simplex available across APIs and aligning it with dual simplex.
Description check	✅ Passed	The description directly relates to the changeset by stating that primal simplex must be supported across all APIs.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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Inline comments:
Review comments at
@python/cuopt/cuopt/linear_programming/solver_settings/solver_settings.pyx:
- Line 65: Keep SolverMethod.Primal as a compatibility member with value 4 while
retaining PrimalSimplex; emit a DeprecationWarning when callers access Primal
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📥 Commits

Reviewing files that changed from the base of the PR and between e8d0b44 and 49b1fa5.

⛔ Files ignored due to path filters (3)

• cpp/src/grpc/codegen/generated/cuopt_mcp_schema.json is excluded by !**/generated/**
• cpp/src/grpc/codegen/generated/cuopt_remote_data.proto is excluded by !**/generated/**
• cpp/src/grpc/codegen/generated/generated_enum_converters_settings.inc is excluded by !**/generated/**

📒 Files selected for processing (15)

• cpp/include/cuopt/mathematical_optimization/constants.h
• cpp/include/cuopt/mathematical_optimization/pdlp/solver_settings.hpp
• cpp/include/cuopt/mathematical_optimization/pdlp/solver_solution.hpp
• cpp/src/dual_simplex/simplex_solver_settings.hpp
• cpp/src/grpc/codegen/field_registry.yaml
• cpp/src/math_optimization/solver_settings.cu
• cpp/src/pdlp/solve.cu
• java/cuopt/src/main/java/com/nvidia/cuopt/mathematicaloptimization/SolverMethod.java
• java/cuopt/src/test/java/com/nvidia/cuopt/mathematicaloptimization/ProblemModelingTest.java
• python/cuopt/cuopt/linear_programming/solution/solution.py
• python/cuopt/cuopt/linear_programming/solver_settings/solver_settings.pxd
• python/cuopt/cuopt/linear_programming/solver_settings/solver_settings.pyx
• python/cuopt_mcp/tests/test_schema.py
• python/cuopt_self_hosted/cuopt_sh_client/thin_client_solver_settings.py
• python/cuopt_self_hosted/tests/test_solver_settings.py

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[ramakrishnap-nv]

cpp/tests/linear_programming/unit_tests/pdlp_memory_test.cu:213 still uses method_t::Primal (not renamed to PrimalSimplex here) and isn't touched by this PR -- won't compile once Primal is renamed.

[chris-maes]

/ok to test 75db679

[chris-maes]

@ramakrishnap-nv fixed. The previous PR was using an older main without this additional test

[github-actions]

CI Test Summary

✅ All 32 test job(s) passed.

[chris-maes]

/merge