Module metamorphic 

Metamorphic testing for orbital physics invariants.

Per Chen et al. [33], metamorphic testing verifies relations rather than specific outputs. This is critical for physics simulations where exact outputs are unknown but invariant relationships must hold.

Metamorphic Relations

1. Rotation Invariance: Rotating the entire system preserves relative dynamics
2. Time-Reversal Symmetry: Symplectic integrators are time-reversible
3. Mass Scaling: Uniform mass scaling preserves orbital shapes
4. Energy Conservation: Total mechanical energy is preserved
5. Momentum Conservation: Total momentum is preserved (closed system)

References

[33] Chen et al., “Metamorphic testing: a new approach,” Hong Kong UST, 1998.

Structs

MetamorphicResult

Metamorphic test result.

Functions

run_all_metamorphic_tests

Run all metamorphic tests on a state.

test_angular_momentum_conservation

MR-4: Angular Momentum Conservation Test

test_deterministic_replay

MR-5: Deterministic Replay Test

test_energy_conservation

MR-3: Energy Conservation Test

test_rotation_invariance

MR-1: Rotation Invariance Test

test_time_reversal

MR-2: Time-Reversal Symmetry Test