readOGR {rgdal} | R Documentation

## Read OGR vector maps into Spatial objects

### Description

The function reads an OGR data source and layer into a suitable Spatial vector object. It can only handle layers with conformable geometry features (not mixtures of points, lines, or polygons in a single layer). It will set the spatial reference system if the layer has such metadata.

### Usage

    readOGR(dsn, layer, verbose = TRUE)
    ogrInfo(dsn, layer)
    ogrFIDs(dsn, layer)

### Arguments

`dsn` | data source name (interpretation varies by driver — for some drivers, dsn is a file name, but may also be a folder)
`layer` | layer name (varies by driver, may be a file name without extension)
`verbose` | report progress

### Details

The drivers available will depend on the installation of GDAL/OGR, and can vary. Note that stray files in data source directories (such as *.dbf) may lead to suprious errors that accompanying *.shp are missing.

### Value

A Spatial object is returned suiting the vector data source, either a SpatialPointsDataFrame (using an AttributeList for its data slot directly), a SpatialLinesDataFrame, or a SpatialPolygonsDataFrame.

### Note

The bases for this implementation are taken from functions in Barry Rowlingson's draft Rmap package, and from Radim Blazek's v.in.ogr program in GRASS.

### Author(s)

Roger Bivand

### References

http://www.remotesensing.org/gdal/ogr/index.html, http://www.remotesensing.org/gdal/ogr/ogr_formats.html, http://examples.oreilly.com/webmapping/

### See Also

`SpatialPointsDataFrame-class`, `SpatialLinesDataFrame-class`, `SpatialPolygonsDataFrame-class`, `readShapePoly`

### Examples

    cities <- readOGR(system.file("vectors", package = "rgdal")[1], "cities")
    summary(cities)
    kiritimati_primary_roads <- readOGR(system.file("vectors", package = "rgdal")[1], "kiritimati_primary_roads")
    summary(kiritimati_primary_roads)
    scot_BNG <- readOGR(system.file("vectors", package = "rgdal")[1], "scot_BNG")
    summary(scot_BNG)
    places <- try(readOGR(system.file("vectors/places.gml", package = "rgdal")[1], "places"))
    if (class(places) != "try-error") summary(places)
    ps_cant_31 <- readOGR(system.file("vectors/ps_cant_31.MIF", package = "rgdal")[1], "ps_cant_31")
    summary(ps_cant_31)
    Up <- readOGR(system.file("vectors/Up.tab", package = "rgdal")[1], "Up")
    summary(Up)

[Package rgdal version 0.4-4 Index]