Particle fields

Particle fields use the same cell-local storage as particle coordinates. Create them with init_cell_arrays so their slots and backend match particles:

pT, pρ, = init_cell_arrays(particles, Val(2))

The returned fields can be scalar or tuple-valued. Tuple allocation is useful for vector quantities:

pV = init_cell_arrays(particles, Val(2))
particle2grid!((Vx, Vy), pV, particles)

Pass companion fields through movement and injection routines so values stay attached to their particles:

move_particles!(particles, (pT, pρ))
inject_particles!(particles, (pT, pρ))

Only active particle slots contain valid values. Unused slots are represented by the occupancy/index mask and must not be included in reductions.

For a field with explicit cell-array dimensions, use cell_array:

phase = cell_array(backend, zero(Float32), (nphases,), size(particles.index))

See CellArrays for halo exchange, indexing, and conversion details.