Shell tools or scripts to split GPX files based on time

gpsbabel can do the low-level filtering for you, but it is a bit awkward, especially if your GPX file has more than one data type (route, track, or waypoint). You would then have to wrap this in a script to process by month or day or whatever.

Here are some examples.

If you have a GPX file of only tracks, and you want only tracks from the year 2014 (2014-01-01 to 2015-01-01), you could use something like this:

gpsbabel -i gpx -f in.gpx \
   -x track,start=20140101,stop=20150101 \
   -o gpx -F out.gpx

Make sure none of your tracks crosses the start or stop date/times, because gpsbabel filters the trackpoints (not the tracks) by trackpoint date/time, and you will end up with partial tracks.

If your GPX file has only waypoints, you have to transform them to use the filter:

gpsbabel -i gpx -f in.gpx \
    -x transform,trk=wpt,del \
    -x track,start=20140101,stop=20150101 \
    -x transform,wpt=trk,del \
    -o gpx -F out.gpx

If your GPX file has both waypoints and tracks, you have to run 2 passes, once per type. Then merge the results (if desired).

gpsbabel -i gpx -f in.gpx \
    -x nuketypes,tracks,routes \
    -x transform,trk=wpt,del \
    -x track,start=20140101,stop=20150101 \
    -x transform,wpt=trk,del \
    -o gpx -F out_w.gpx

gpsbabel -i gpx -f in.gpx \
    -x nuketypes,waypoints,routes \
    -x track,start=20140101,stop=20150101 \
    -o gpx -F out_t.gpx
gpsbabel -i gpx -f out_w.gpx -f out_t.gpx -o gpx -F out.gpx

Doing this for routes 'is left as an exercise for the reader'.