Function to filter temporally and spatially exact locations in tracking data.
dupfilter_exact(sdata)
A data frame containing columns with the following headers: "id", "DateTime", "lat", "lon", "qi".
The function filters the input data by the unique "id".
"DateTime" is date & time in class POSIXct
.
"lat" and "lon" are the latitude and longitude of each location in decimal degrees.
"qi" is the numerical quality index associated with each location fix where a greater number indicates a higher accuracy
(e.g. the number of GPS satellites involved in estimation).
The input data frame is returned with temporally and spatially exact duplicates removed.
This is a partial component of dupfilter
, although works as a stand-alone function.
It looks for temporally and spatially exact locations and retains only a single fix (latitude/longitude pair) per time and location.
Shimada T, Limpus C, Jones R, Hazel J, Groom R, Hamann M (2016) Sea turtles return home after intentional displacement from coastal foraging areas. Marine Biology 163:1-14 doi:10.1007/s00227-015-2771-0
dupfilter
, dupfilter_qi
, dupfilter_time
, dupfilter_space
, track_param