I have a python file with imported rdflib and some SPARQL query implemented
from rdflib import Graph
import html5lib
if __name__ == '__main__':
g = Graph()
g.parse('http://localhost:8085/weather-2.html', format='rdfa')
res1 = g.parse('http://localhost:8085/weather-2.html', format='rdfa')
print(res1.serialize(format='pretty-xml').decode("utf-8"))
print()
res2 = g.query("""SELECT ?obj
WHERE { <http://localhost:8085/weather-2.html> weather:region ?obj . }
""")
for row in res2:
print(row)
res1 has no trouble to print out but for res2 I get an error saying:
Exception: Unknown namespace prefix : weather
Apparently this is due to an error on line 15 according to pycharm, the editor I am using to implement this.
What am I missing that is causing this error?
Is there more to just calling weather:region
in my SPARQL query?
If so how to do fix this problem?
As the error message suggests, the namespace weather:
is not defined - so in the SPARQL you either need a PREFIX to define weather, like:
PREFIX weather: <weatheruri>
Or you should put the explicit weather URI instead of the weather:
The weather namespace URI (or is it called an IRI?) will be in the XML namespaces in the rdf document - it will end with / or # so if the URI is http://weather.com/
the prefix definition is PREFIX weather: <http://weather.com/>