Sensible defaults are assumed, to match the extents of data to a manageable grid.

makeGridTopology(
  obj,
  cells.dim = c(100, 100),
  xlim = NULL,
  ylim = NULL,
  buffer = 0,
  cellsize = NULL,
  adjust2longlat = FALSE
)

Arguments

obj

any Spatial object, or other object for which bbox will work

cells.dim

the number of cells of the grid, x then y

xlim

x limits of the grid

ylim

y limits of the grid

buffer

proportional size of the buffer to add to the grid limits

cellsize

pixel cell size

adjust2longlat

assume cell size is in kilometres and provide simple adjustment for earth-radius cells at the north-south centre of the grid

Details

Approximations for kilometres in longlat can be made using cellsize and adjust2longlat.