VDP–MATHIEU · ≤650 · DRAG PAN · PINCH ZOOM · TAP SEED
REDUCED MOTION · SETTLED ATTRACTOR
a
0.50
SPEED (dt)
0.02
FADE
0.08
PRESETS
Van der Pol–Mathieu — ẋ=y, ẏ=a(1−x²)y−(1+0.5 cos 2z)x, ż=1. Phase-wrap z. Classic a=0.5. Distinct from mathieu-vanderpol.html. RK4. Gold trail, cap 650. RM = settled silhouette, no animate-on.