as.SpatialPolygons.GridTopology {sp} | R Documentation |
Converts grids of regular rectangles into a SpatialPolygons
object, which can be transformed to a different projection or datum. The function is not suitable for high-resolution grids. The ordering of the grid cells is as in coordinates()
of the same object, and is reported by IDvaluesGridTopology
.
as.SpatialPolygons.GridTopology(grd, proj4string = CRS(as.character(NA))) IDvaluesGridTopology(obj)
grd,obj |
GridTopology object |
proj4string |
projection string of class CRS |
as.SpatialPolygons.GridTopology
returns a SpatialPolygons
object;
IDvaluesGridTopology
returns a character vector with the GridTopology
object column and row indices.
grd <- GridTopology(cellcentre.offset=c(-175,55), cellsize=c(10,10), cells.dim=c(4,4)) SpP_grd <- as.SpatialPolygons.GridTopology(grd) plot(SpP_grd) text(getSpPPolygonsLabptSlots(SpP_grd), getSpPPolygonsIDSlots(SpP_grd), cex=0.5) trdata <- data.frame(A=rep(c(1,2,3,4), 4), B=rep(c(1,2,3,4), each=4), row.names=getSpPPolygonsIDSlots(SpP_grd)) SpPDF <- SpatialPolygonsDataFrame(SpP_grd, trdata) spplot(SpPDF)