eco.l3.ut {spsurvey} | R Documentation |
This dataset is a list composed of two element, each of which is a matrix containing the x-coordinates and y-coordinates for a polygon.
data(eco.l3.ut)
A list containing two elements:
1
2
This dataset is a subset of the Level III ecoregions in Utah. Further information regarding ecoregions is available at the following web site: http://www.epa.gov/wed/pages/ecoregions.htm
Omernik, J.M., (1987). Ecoregions of the conterminous United States. Annals of Association of American Geographers, 77, 1-118.
# This example converts the dataset to an sp package object data(eco.l3.ut) n <- length(eco.l3.ut) nparts <- rep(1, n) ringdir <- rep(1, n) IDs <- as.character(1:n) shapes <- vector(mode="list", length=n) for(i in 1:n) { shapes[[i]] <- list(Pstart=0, verts=eco.l3.ut[[i]], nVerts=nrow(eco.l3.ut[[i]]), nParts=nparts[i]) attr(shapes[[i]], "RingDir") <- ringdir[i] } PolygonsList <- vector(mode="list", length=n) for(i in 1:n) { PolygonsList[[i]] <- shape2spList(shape=shapes[[i]], shp.type="poly", ID=IDs[i]) } att.data <- data.frame(id=1:n, area=1:n) for(i in 1:n) { att.data$area[i] <- PolygonsList[[i]]@area } rownames(att.data) <- IDs sp.obj <- SpatialPolygonsDataFrame(Sr=SpatialPolygons(Srl=PolygonsList), data=att.data) # To convert the sp package object to a shapefile use the following code: # sp2shape(sp.obj, "eco.l3.ut")