Number of mapped keys for the maps in package sysptm.db

Description

sysptmMAPCOUNTS provides the "map count" (i.e. the count of mapped keys) for each map in package sysptm.db.

Details

This "map count" information is precalculated and stored in the package annotation DB. This allows some quality control and is used by the checkMAPCOUNTS function defined in AnnotationDbi to compare and validate different methods (like count.mappedkeys(x) or sum(!is.na(as.list(x)))) for getting the "map count" of a given map.

See Also

mappedkeys, count.mappedkeys, checkMAPCOUNTS

Examples

  sysptmMAPCOUNTS
  mapnames <- names(sysptmMAPCOUNTS)
  sysptmMAPCOUNTS[mapnames[1]]
  x <- get(mapnames[1])
  sum(!is.na(as.list(x)))
  count.mappedkeys(x)   # much faster!