map2list {GeoXp} | R Documentation |
The function `map2list' calculates the middle coordinates of boundary box and in the case where polygons are included into the `Map' object, it extracts the vertices of the polygons, seperating polygons from each other by 3 rows of NaN.
map2list(data)
data |
A `Map' object |
The user can then represent the coordinates of sites of a `Map' object as background map, using the option `carte' included in all interactive functions.
It returns two vectors of middle coordinates for x-axis and y-axis cooresponding to middle of each boundary box. It returns a matrix of numeric values with 2 columns ($x$ and $y$ coordinates of the vertices of the polygons) where polygons are seperated from each other by 3 rows of NaN.
The data of a `Map' object can be directly extract using $att.data
Thibault Laurent
Bivand R. (2008), `The maptools package', http://cran.r-project.org/doc/packages/maptools.pdf.
x <- read.shape(system.file("shapes/columbus.shp", package="maptools")[1]) colombus.contours<-map2list(x) colombus<-x$att.data