Instead of creating ghost cells, cell pairs that interact over a periodic boundary can also use a periodic correction vector . This vector, which can be stored or computed for every cell pair contains the correction which needs to be applied to "wrap" one cell around the domain to neighbour the other. The pairwise distance between two particles and is then computed as
This approach, although more efficient than using ghost cells, is less straightforward to implement (the cell pairs need to be identified over the periodic boundaries and the vector needs to be computed/stored).
Famous quotes containing the word periodic:
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