sda: Filter track for speed, distance and angle.
Description
Create a filter index of a track for "bad" points with a
combination of speed, distance and angle tests.Usage
sda(x, smax, ang = c(15, 25), distlim = c(2.5, 5), pre = NULL)
Arguments
smax
maximum speed, in km/h
ang
minimum turning angle/s in degrees
distlim
maximum step lengths in km
pre
include this filter in the removal
Value
- logical vector, with
FALSE values where the tests failed
Details
This is an independent implementation from that in the
package argosfilter by Frietas 2008.References
Freitas, C., Lydersen, C., Fedak, M. A. and Kovacs,
K. M. (2008), A simple new algorithm to filter marine mammal Argos
locations. Marine Mammal Science, 24: 315?V325. doi:
10.1111/j.1748-7692.2007.00180.x