When trying to access the extra-info field for a track, it may happen that it is not filled. This can get annoying f. ex. when dumping an nTuple, where only the standard value is filled, like:

tuple->column( head+"_TrNExpectedTT", track->info(LHCb::Track::nExpectedTT, -100.) ); 

The extra-info field is filled in the algorithm 'TrackAddLikelihood' in 'TrackAddExtraInfoSeq'.

• Check if the algorithm is really in this sequence.
• If yes, but the fields are still not filled, give the inputLocation of the Tracks you want the information from manually, f.ex.

TrackAddLikelihood("TrackAddLikelihood").inputLocation = "Rec/Track/Forward" 

Note the LOWERCASE 'i' of 'inputLocation'!

This should solve the problem.