Escape from the cell: Spatially explicit modelling with and without grids

摘要: This paper is concerned with the representation of individuals embedded in a two- (or three-) dimensional environment, and techniques that can be used to simulate evolution spatial patterns both populations those their environment. Its scope therefore individual based or agent modelling, general type, including herbivore populations, predator-prey models any other type patterning evolving from recruitment, interaction and/or movement discrete individuals. The aim discuss modelling technique allows more flexibility positions than typically case for cellular automata (CA), but which also deals efficiently problem searching neighbours when vary nearly continuously. A scaling discussed arises range over interact much smaller size domain. It argued validation CA involving made difficult system scale exceeds by large factor. However, even domain small, if between mediated size, imposition fixed grid upon dynamics may cause important phenomena misrepresented missed altogether. We suggest automata, as usually formulated, do not deal adequately this problem, introduce particle-in-cell (PIC) method it intermediate cases. Alternative data structures are dealing extreme cases, possibility an indefinitely using changing set cells (PIC:SI).