Many annotation tracks are actually composed of a number of grouped sub-features, for instance exons in a gene model. This man page highlights the use of grouping information to build informative annotation plots.

Details

All track objects that inherit from class AnnotationTrack support the grouping feature. The information is usually passed on to the constructor function (for AnnotationTrack via the groups argument and for GeneRegionTrack objects via the exon argument) or automatically downloaded from an online annotation repository (BiomartGeneRegionTrack). Group membership is specified by a factor vector with as many items as there are annotation items in the track (i.e., the value of length(track). Upon plotting, the grouped annotation features are displayed together and will not be separated in the stacking of track items.

Author

Florian Hahne