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sp (version 0.9-78)

SpatialPolygons: create objects of class SpatialPolygons or SpatialPolygonsDataFrame

Description

create objects of class SpatialPolygons or SpatialPolygonsDataFrame from lists of Polygons objects and data.frames

Usage

Polygon(coords, hole=as.logical(NA))
Polygons(srl, ID)
SpatialPolygons(Srl, pO, proj4string=CRS(as.character(NA)))
SpatialPolygonsDataFrame(Sr, data, match.ID = TRUE)
getSpatialPolygonsLabelPoints(SP)

Arguments

coords
2-column numeric matrix with coordinates; first point (row) should equal last coordinates (row); if the hole argument is not given, the status of the polygon as a hole or an island will be taken from the ring direction, with clockwise meaning island, and
hole
logical value for setting polygon as hole or not; if the hole argument is not given, the status of the polygon as a hole or an island will be taken from the ring direction, with clockwise meaning island, and counter-clockwise meaning hole
proj4string
projection string of class CRS-class
srl
list with Polygon-class objects
ID
character vector of length one with identifier
Srl
list with objects of class Polygons-class
pO
integer vector; plotting order; if missing in reverse order of Polygons area
Sr
object of class SpatialPolygons-class
data
object of class data.frame; the number of rows in data should equal the number of Polygons-class objects in Sr
match.ID
logical: (default TRUE): match SpatialPolygons member Polygons ID slot values with data frame row names, and re-order the data frame rows if necessary. If character: indicates the column in data with Polygons IDs to match
SP
object of class SpatialPolygons-class

Value

  • Polygon returns an object of class Polygon; Polygons returns an object of class Polygons; SpatialPolygons returns object of class SpatialPolygons; SpatialPolygonsDataFrame returns object of class SpatialPolygonsDataFrame getSpatialPolygonsLabelPoints returns an object of class SpatialPoints with label points.

Details

In Polygon, if the hole argument is not given, the status of the polygon as a hole or an island will be taken from the ring direction, with clockwise meaning island, and counter-clockwise meaning hole. In Polygons, if all of the member Polygon objects are holes, the largest by area will be converted to island status. Until 2010-04-17, version 0.9-61, the area of this converted object was erroneously left at its hole value of zero. Thanks to Patrick Giraudoux for spotting the bug.

See Also

SpatialPolygons-class, SpatialPolygonsDataFrame-class