intamap (version 1.5-7)

coarsenGrid: Coarsening of a spatial grid

Description

coarsenGrid is a function that resamples a SpatialGridDataFrame.

Usage

coarsenGrid(object,coarse=2,offset = sample(c(0:(coarse-1)),2,replace=TRUE))

Value

a SpatialGridDataFrame.

Arguments

object

a SpatialGridDataFrame or gridded SpatialPixelsDataFrame

coarse

an integer telling how much the grid should be coarsened

offset

integer giving the relative offset of the first point, see details below for a closer description

Author

Jon Olav Skoien

Details

The function coarsenGrid is a function that samples from a SpatialGridDataFrame. The argument coarse indicates that every coarse row and column will be sampled, starting with the row and column represented in offset. offset = c(0,0) implies that the smallest x- and y-coordinates will be a part of the resampled data set, offset = c(1,1) implies that sampling will start on the second row and column.

References

Pebesma, E., Cornford, D., Dubois, G., Heuvelink, G.B.M., Hristopulos, D., Pilz, J., Stohlker, U., Morin, G., Skoien, J.O. INTAMAP: The design and implementation of an interoperable automated interpolation Web Service. Computers and Geosciences 37 (3), 2011.

Examples

data(meuse.grid)
gridded(meuse.grid) = ~x+y
newMeuseGrid = coarsenGrid(meuse.grid,coarse=2,offset=c(1,1))