Entity Relatedness Task fails when there are 2 vectors for the same URI

[janothan]

Situation: On accident, in the vector text file one concept appears twice, e.g.:

http://dbpedia.org/resource/Schengen_Agreement 0.7 -0.1 0.2 0.3
http://dbpedia.org/resource/Schengen_Agreement 0.7 -0.1 0.2 0.3

This will fail later on (maybe also on other tasks).
A nicer behavior would be when, while loading the vectors, a warning would be printed in the log and just one vector for that particular URI would be used in the data frame.