Add a per-track sequential fix index and a globally-unique fix identifier
Usage
add_fix_id(x, overwrite = FALSE)
Arguments
- x
A track_tbl with columns id, lon, lat, time.
- overwrite
Logical; if FALSE (default) and fixID already exists,
an error is thrown to avoid accidental reassignment. Set TRUE to recompute.
Value
The same track_tbl with:
fixN: integer 1,2,3,... within each id ordered by time (ties by lon/lat)
fixID: character unique identifier paste(id, fixN, sep = "_")
