I have a shapefile with point data that contains all the locations and times (essentially a tracklog) of animals wearing GPS satellite collars. I would like to be able select/query the locations of all the animals for a particular date, however I run into a problem because each animal may not necessarily have a location feature for that date or it may have more than one feature for that date. I need it to report the first location for each animal after said date.
To clarify if I have 25 animals, I might have 20,000 locations in the data file and if I query for all the locations on May 1st then I want the first location for each animal on or after May 1st.
Currently I have to go through the file and manually select a feature for each animal. This will become very time consuming as I get more collars or work with older datasets.
Help is greatly appreciated.
To clarify if I have 25 animals, I might have 20,000 locations in the data file and if I query for all the locations on May 1st then I want the first location for each animal on or after May 1st.
Currently I have to go through the file and manually select a feature for each animal. This will become very time consuming as I get more collars or work with older datasets.
Help is greatly appreciated.