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I imported several GPX files and added a raster basemap for reference. The GPX files contains tracks so the points are sequentially numbered. I'd like to identify one of the points so I edit the GPX file and remove unwanted data (there is a bunch of unwanted data, miles and miles). The easiest way, I think, is to identify the last desired point, grab it's ID, and delete all points after / before it from the source file.

How do I select a point and get it's attributes like ID, lat / lon, elev, etc.?

I'm using QGIS 2.6.0 (Brighton).

Update #1 - I will edit the GPX file myself using an external app. I just need to ID the point.

Update #2 - I already have the files imported. Now that I can see where the points fall, I want to select one of the points to get an identifying attribute to use for modifying the track data. For example, my study area stops at an intersection of two roads. I want to grab the point nearest that intersection (ID, timestamp, some identifying attribute) and delete from the source file all points outside my study. Does QGIS have a tool that alows me to pick a point on screen and display the point's attributes? If not, how about a series of steps I can perform to get the information? I have an extensive CAD / engineering background and this is a feature in every CAD package I've used. I just need to know if it exists in QGIS and if so, where it is.

Update #3 - I found the Attribute Table for the layer but could not find a tool to graphically select a point and display its attributes. Getting closer...

  • The only possible way to edit a gpx file is convert it to and editable format such as shp. – Gerardo Jimenez Nov 13 '14 at 3:27
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In QGIS, you can add a GPX file using Add Vector Layer. In a dialogue you will be asked for the layers you want:

  • waypoints
  • tracks
  • track_points
  • routes
  • route_points

You get the track points with attributes using the track_points layer.

The alternative method of adding GPX files with the GPS Tool does not offer the trackpoints layer.

By the way, track points are not numbered in original GPX format:

<trkpt lat="51.320262" lon="7.132114">
 <ele>181.000000</ele>
 <time>2014-05-04T07:25:03Z</time>
 <desc>Lat.=51.320262, Long.=7.132114, Alt.=181.000000m, Speed=2Km/h, Course=140deg.</desc>
</trkpt>
<trkpt lat="51.320227" lon="7.132158">
 <ele>181.000000</ele>
 <time>2014-05-04T07:25:08Z</time>
 <desc>Lat.=51.320227, Long.=7.132158, Alt.=181.000000m, Speed=3Km/h, Course=142deg.</desc>
</trkpt>

They get an internal ID when they are imported into QGIS as points. You can compare the time stamp though.

  • I have the data imported as vector data with track points. How do I view the attributes of a specific point? Once I have that, I'll modify the source files. At this point, I can't figure out how to view the attributes of an individual point selected graphically. I found the Attribute Table on the Layer but I can't sift through 100K points manually. – DenaliHardtail Nov 13 '14 at 20:35
  • Select the point layer in the legend, then use the identify tool (the icon with the white i on a blue circle) to get the attributes of a point. In Settings -> Options, Data Source tab you can set the attribute table to Show features visible on map to avoid looking at all entries. In the attribute table, you can select a feature row and zoom or move to that with the pan or lense icon. – AndreJ Nov 14 '14 at 4:54
  • YES!!! That's all I wanted. I found the identify button earlier but was not selecting the layer before trying to ID an entity. – DenaliHardtail Nov 15 '14 at 0:07
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My method is to come outside QGIS completely. The Openstreetmap editor 'JOSM' is easy to download. There's a plugin for it called GPS Infomode. This makes it super-easy to display the information from each GPX track point. I write down the time for a point where I want to cut data out of the gpx file. Then I open the gpx in Notepad++ (or another good xml/text editor). I use plugins for this to display the gpx in an easy-to-read format. Then I do the deletions by hand in the text. With a good text editor this can be quick - with the plugins you can check you've not done anything silly to the xml file.

One minor point is to note that JOSM can display the information in local time, when what you're looking for is the time in GMT (which is how it's in the GPX file).

I'm waiting to find a better solution, but until I do this can be a pretty efficient method.

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