Im triyng to filter a gps location data.frame. I have gps locations obtained by 5 mins interval and other obtained by 1 second interval (and consequently the same minute is repeated along with dataset eg 2010-12-14 10:12:23; 10:12:24 and so on.
In order to homogenize my dataset i want to only left those locations by 5 mins interval. I have tried using this script;
require (lubridate)
bird < -with (alis, alis [minutes (datetime) > = 5,])
But it did not work
Any idea? subsetting? xts package ...?
Thanks in advance Jon