我正在尝试将数据集的名称添加到图形对象,然后再检索它们,非常确定必须有一种简单的方法来完成它,但是到目前为止找不到任何东西…谢谢
解决方法:
我认为您正在寻找的是将上下文附加到图形.这就像创建一个图来解析其中的子图,每个子图都有一个名称-如果是rdflib,则为URIRef.
假设您必须使用以下两个文件表示的图形:
数据代理
<http://data.org/inst1> <http://xmlns.com/foaf/0.1/name> "david" .
<http://data.org/inst2> <http://xmlns.com/foaf/0.1/name> "luis" .
<http://data.org/inst3> <http://xmlns.com/foaf/0.1/name> "max" .
dataB.nt
<http://data.org/inst1> <http://xmlns.com/foaf/0.1/knows> <http://data.org/inst2> .
<http://data.org/inst2> <http://xmlns.com/foaf/0.1/knows> <http://data.org/inst3> .
<http://data.org/inst3> <http://xmlns.com/foaf/0.1/knows> <http://data.org/inst1> .
和以下代码:
import rdflib
g = rdflib.ConjunctiveGraph("IOMemory",)
#g is made of two sub-graphs or triples gathered in two different contexts.
#the second paramaters identifies the URIRef for each subgraph.
g.parse("dataA.nt",rdflib.URIRef("http://mygraphs.org/names"),format="n3")
g.parse("dataB.nt",rdflib.URIRef("http://mygraphs.org/relations"),format="n3")
print "traverse all contexts and all triples for each context"
for subgraph in g.contexts():
print "Graph name",subgraph.identifier
for triple in subgraph.triples((None,None,None)):
print triple
print "traverse all contexts where a triple appears"
for subgraph in g.contexts(triple=(rdflib.URIRef('http://data.org/inst1'),rdflib.URIRef("http://xmlns.com/foaf/0.1/name"),rdflib.Literal(u'david'))):
print "Graph name",subgraph.identifier
for triple in subgraph.triples((None,None,None)):
print triple
print "traverse a triple pattern regardless the context is in"
for t in g.triples((None,rdflib.URIRef("http://xmlns.com/foaf/0.1/name"),None)):
print t