Neural ODE Pocket learns a continuous vector field for the Van der Pol oscillator
and integrates it with fourth-order Runge–Kutta. An exactly 1,218-parameter
black-box transition network is trained on the same one-step examples.
Both models train only at timestep 0.05. Evaluation measures 20 units of
closed-loop physical time at both the trained timestep and an unseen timestep of
0.20, separating continuous-time structure from discrete transition fitting.
At exactly 1,218 parameters per model, RK4 neural dynamics reached 0.227
trajectory RMSE at both trained and four-times-larger unseen timesteps. The
discrete model rose from 0.607 to 2.212 RMSE. Mean unseen-timestep horizon before
state error exceeded 0.5 was 48.46 steps for the neural ODE versus 1.88.
1uv run python projects/neural-ode-pocket/train.py
2uv run pytest tests/test_neural_ode_pocket.py