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name: physo description: "Use PhySO for symbolic regression, class symbolic regression, toolkit-level expression workflows, and benchmark problem loaders." read_when: "Use when the user names physo, PhySO, symbolic regression, ClassSR, toolkit expression helpers, or benchmark problem loaders." disable-model-invocation: true metadata: disco-role: operating license: MIT

PhySO

Use this skill when working with the physo package, the scientific Python symbolic-regression library.

Install and Import Check

Run scripts/physo_skill_doctor.py to confirm the installed package, key public exports, and the CPU scientific stack used by the verified baseline. The checked baseline was PhySO 1.2.0 on CPU; this skill does not claim CUDA verification. Import-time LaTeX warnings are expected when optional display tools are missing.

Route by Task

• One dataset with X, y, units, y_weights, candidate_wrapper, run presets, logging, or Pareto inspection: use sub-skills/sr/SKILL.md.
• Multiple realizations with shared class constants or realization-specific constants: use sub-skills/class-sr/SKILL.md.
• Prefix expressions, libraries, tokens, Program/VectPrograms, random sampling, constant optimization, display, or result reloads: use sub-skills/toolkit/SKILL.md.
• Feynman/Class benchmark problems, sample generation, metadata, or symbolic equivalence checks: use sub-skills/benchmarks/SKILL.md.

Shared References

• references/install-and-smoke.md: install/import check and smoke commands.
• references/troubleshooting.md: cross-cutting import, display, backend, and routing failures.
• references/repo-provenance.md: source version, dirty-state snapshot, and evidence paths.
• references/repo-routing-metadata.json: router placement metadata for compatible agents.

Common Starting Points

• Start with the doctor script when the environment or package import is uncertain.
• Route to a sub-skill before drafting commands or code for a user workflow.
• Use the sub-skill smoke scripts for route-specific tiny checks after the environment is known to be usable.
• If the user asks for benchmark reproduction, training-scale sweeps, or maintainer jobfiles, stop at the boundary and keep this runtime skill focused on day-to-day package workflows.

Boundaries

This skill is self-contained. It does not depend on opening the source checkout at runtime, and it does not cover repo maintenance, release automation, or long benchmark campaigns.