waxmorph.emulator.diffusion_step_differentiable

waxmorph.emulator.diffusion_step_differentiable(tape, X, R, c, particle_count, D_emu=0.1, dt=0.01, grid=None)

Record graph diffusion with concentration gradients.

Positions, radii, and pair discovery remain outside the tape. Each molecule channel diffuses independently over the frozen topology. The caller seeds c_out.grad and replays tape.

Parameters:

• tape (Tape)

• X (array)

• R (array)

• c (array)

• particle_count (int)

• D_emu (float)

• dt (float)

• grid (HashGrid | None)

Return type:

array