Reading and writing of "ESRI shapefile" format spatial data. Only the three vector types (points, lines, and polygons) can be stored in shapefiles.
These are simple wrapper functions around readOGR and writeOGR (rgdal package).
A shapefile should consist of at least four files: .shp (the geometry), .dbf (the attributes), .shx (the index that links the two, and .prj (the coordinate reference system). If the .prj file is missing, a warning is given. If any other file is missing an error occurs (although one could in principle recover the .shx from the .shp file). Additional files are ignored.
# S4 method for character
shapefile(x, stringsAsFactors=FALSE, verbose=FALSE, warnPRJ=TRUE, ...)
# S4 method for Spatial
shapefile(x, filename='', overwrite=FALSE, ...)
character (a file name, when reading a shapefile) or Spatial* object (when writing a shapefile)
character. Filename to write a shapefile
logical. Overwrite existing shapefile?
logical. If TRUE, information about the file is printed
logical. If TRUE, a warning is given if there is no .prj file
logical. If TRUE, strings are converted to factors
Additional arguments passed to rgdal functions readOGR or writeOGR
Spatial*DataFrame (reading). Nothing is returned when writing a shapefile.