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I'm an absolute newbie but I think I'm doing this right.

I've got a bunch of .fit files from my garmin. I can use GPSBabel to manually convert these to GPX XML and the map looks fine after the conversion. If I open the file it looks fine.

I then use Vector | GPS | GPS Tools to import the gpx file. The layer is created but there's nothing to see on the map. If I go to the Attribute Table there is only one line and it's full of nulls.

Is there are better output file type in GPS Babel that qgis prefers?

<?xml version="1.0" encoding="UTF-8"?>
<gpx version="1.1" creator="GPSBabel - http://www.gpsbabel.org" xmlns="http://www.topografix.com/GPX/1/1" xmlns:gpxx="http://www.garmin.com/xmlschemas/GpxExtensions/v3" xmlns:gpxtpx="http://www.garmin.com/xmlschemas/TrackPointExtension/v1">
  <metadata>
    <time>2014-04-25T05:42:52.371Z</time>
    <bounds minlat="-36.755794164" minlon="174.555711483" maxlat="-36.722196898" maxlon="174.580664325"/>
  </metadata>
  <trk>
    <trkseg>
      <trkpt lat="-36.755794164" lon="174.563342619">
        <ele>42.200000</ele>
        <time>2014-04-24T22:28:41Z</time>
        <extensions>
          <gpxtpx:TrackPointExtension>
            <gpxtpx:atemp>27.000000</gpxtpx:atemp>
          </gpxtpx:TrackPointExtension>
        </extensions>
      </trkpt>
      <trkpt lat="-36.755728199" lon="174.563325436">
        <ele>42.200000</ele>
        <time>2014-04-24T22:28:45Z</time>
        <extensions>
          <gpxtpx:TrackPointExtension>
            <gpxtpx:atemp>27.000000</gpxtpx:atemp>
          </gpxtpx:TrackPointExtension>
        </extensions>
      </trkpt>
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  • Can you insert a part of the gpx file into your question? You can open it with any text editor. Alternatively, you can use Add Vector layer to load GPX files.
    – AndreJ
    Apr 25, 2014 at 6:19
  • I just closed the program, then reopened to check something and my track was showing. still null in attributes but atleast I have my track!
    – Sarah K
    Apr 25, 2014 at 6:31
  • Which Garmin device?
    – Mapperz
    Apr 25, 2014 at 13:41
  • I've got an Edge 500 which outputs .fit files which are converted using GPSBabel. The problem was a glitch, hasn't happened again and I've learnt what the attributes are all about.
    – Sarah K
    May 5, 2014 at 2:05

2 Answers 2

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The attribute table has only NULL values because no track name is given in the GPX file. The other attribute fields are NULL in most cases.

Date, time and elevation are point attributes, they do not get into the track attribute table.

It might help to zoom to layer extent if you don't see the line after import.


EDIT

You get elevation and timestamps if you import the GPX with Add Vector layer, then select the track_points layer.

It depends on the GPS model which values are extracted directly, and which are stored in the desc field.

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I can think of a few things you might need to know - and which might relate to your question. I'm also relatively new to this, and I'm speaking from the limits of my knowledge, so quite happy if others correct fine points (or indeed big errors) in my answer...

I suspect that not seeing the line might relate to the colour of the line, or not looking at the right place (geographically), rather than it not actually being displayed.

As Andre Joost says, the 'null' values are because the line itself (defined by ) does not have any additional data associated with it (e.g. name).

I don't remember the detail, but I suspect that each (if more than one in a file) will appear as a separate line with separate attribute row.

I specifically see time and elevation information in the xml. This is associated with the points not the line... I'm sure it's possible to get this into QGIS too, so you end up with a set of points each with a row of data. I've not personally done this. What we're dealing with here is that a gpx file does something relatively special, in combining both point and line data in one.... which gis software doesn't normally do in any automatic way.

EDIT: See Andre's additional edit to his answer for added details on the question of getting the points information rather than the line information.

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  • I've applied a steep learning curve and can now see how attribute files are used when I started adding new layers with extra information. It's an amazing system!
    – Sarah K
    Apr 27, 2014 at 5:52

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