CONTRIBUTING.md

Contributing — dev

Branch dev is the integration branch for micro-opts. main is stable (712 routines). PRs target dev.

Workflow

1. Branch git checkout -b feat/my-opt dev (not main).
2. Check ref numpy-reference/reference/generated/numpy.<func>.html — match Python signature exactly (see AGENTS.md).
3. Implement in include/np/<module>.hpp with Doxygen Reference: link and NP_API.
4. Test tests/test_<module>.cpp using tests/test_util.hpp (test::check, approx).
5. Format clang-format -i include/np/*.hpp — .clang-format: 4-space, custom Allman-style braces, ColumnLimit: 120, UseTab: Never.
6. Build cmake -S . -B build && cmake --build build -j8 && ctest --test-dir build --output-on-failure — must be 49/49.
7. Commit feat(module): ... with file:line (e.g. ndarray.hpp:3116). One logical task per commit, no build/ artifacts (CMakeCache.txt, build/ are in .gitignore).
8. PR to dev — include bench delta if perf-related (see PERFORMANCE.md).

Micro-opt guidelines (dev)

• Guard fast path with if (is_contiguous()) [[likely]] + fallback Odometer/_flat_logical for views.
• Use T* __restrict for vector<T>::data() (except vector<bool> proxy — if constexpr fallback).
• reserve vectors before push_back; [[unlikely]] on throw paths.
• std::memcpy only when same shape + is_contiguous() + offset==0.
• Hash threshold 64 for isin (empirical); BLOCK=32 for dot.
• Threadpool via NP_USE_THREADING — parallel_for threshold >4096.
• Add [[nodiscard]], noexcept where appropriate.

Style

• snake_case funcs, PascalCase types, Allman braces, NP_API/NP_NODISCARD.
• Include guards #ifndef NP_<NAME>_HPP.
• Namespace np (sub np::linalg, np::datetime, np::testing).

Docs

• Update README.md (dev badge) and docs/*.md when adding routines.
• Keep file:line in doc tables greppable.
• Run cmake --build build --target bench_math for perf docs.

See AGENTS.md and ARCHITECTURE.md for layout (include/np/detail/* for proxy.hpp, expr.hpp).

Release

dev → main squash after 49/49 + clang-format clean. Tag vX.Y-dev for bench.