polygons: sets spatial coordinates to create spatial data, or retrieves...

In sp: Classes and Methods for Spatial Data

sets spatial coordinates to create spatial data, or retrieves spatial coordinates

Description

sets spatial coordinates to create spatial data, or retrieves spatial coordinates

Usage

	polygons(obj)
	polygons(object) <- value

Arguments

obj	object of class "SpatialPolygons" or "SpatialPolygonsDataFrame"
object	object of class "data.frame"
value	object of class "SpatialPolygons"

Value

polygons returns the SpatialPolygons of obj; polygons<- promotes a data.frame to a SpatialPolygonsDataFrame object

Examples

grd <- GridTopology(c(1,1), c(1,1), c(10,10))
polys <- as.SpatialPolygons.GridTopology(grd)
centroids <- coordinates(polys)
x <- centroids[,1]
y <- centroids[,2]
z <- 1.4 + 0.1*x + 0.2*y + 0.002*x*x
df <- data.frame(x=x, y=y, z=z, row.names=row.names(polys))
polygons(df) <- polys
class(df)
summary(df)

sp documentation built on April 4, 2025, 1:16 a.m.