R: SPARQL client

SPARQL-package {SPARQL} | R Documentation

## SPARQL client

### Description

Load SPARQL SELECT query result tables as a data frame, or UPDATE the triple store by connecting to an end-point over HTTP.

The development of this library has been developed in part within the COMBINE project supported by the ONR Global NICOP grant N62909-11-1-7060.

### Details

Package: | SPARQL
Type: | Package
Version: | 1.15
Date: | 2013-10-23
License: | GPL-3
Depends: | XML
LazyLoad: | yes

### Author(s)

Willem Robert van Hage <willem.van.hage@synerscope.com>, with contributions from: Tomi Kauppinen, Benedikt Graeler, Christopher Davis, Jesper Hoeksema, Alan Ruttenberg, and Daniel Bahls. Maintainer: Willem Robert van Hage <willem.van.hage@synerscope.com>

### References

SPARQL specification, http://www.w3.org/TR/rdf-sparql-query/.
Examples of SPARQL end-points, http://www.w3.org/wiki/SparqlEndpoints.

### Examples

    ## Not run:
    d <- SPARQL(url="http://services.data.gov.uk/reference/sparql",
                query="SELECT * WHERE { ?s ?p ?o . } LIMIT 10",
                ns=c('time','<http://www.w3.org/2006/time#>'))

    is.data.frame(d$results)

    # draw a pie chart from data from the Linked Open Piracy data set
    endpoint <- "http://semanticweb.cs.vu.nl/lop/sparql/"
    q <-
      "SELECT *
       WHERE {
         ?event sem:hasPlace ?place .
         ?place eez:inPiracyRegion ?region .
       } LIMIT 20"
    prefix <- c("lop","http://semanticweb.cs.vu.nl/poseidon/ns/instances/",
                "eez","http://semanticweb.cs.vu.nl/poseidon/ns/eez/")
    res <- SPARQL(endpoint,q,prefix)$results
    pie(sort(table(res$region)),col=rainbow(12))

    ## End(Not run)

[Package SPARQL version 1.16 Index]