Get the file id from file-sets given the type of relation between sets. File-set is defined by the case or filecategory.
getFileIdSets(set = c("case", "filecategory"), relation = c("union", "intersect"))type of set, either "case" or "filecategory".
relation between sets, either "union" or "interset".
A numeric vector or NULL if no file id is well-defined.
File-set is defined by case or file category. Files belonging to a case/filecategory are in a set. This function gets file id from the selected sets. When multiple sets are selected, the relation between them can be defined. When relation is union, file ids from either selected set are returned. When relation is intersect, only file ids that appear in all the selected sets are returned.