Dissecting a .gpx file

Discussion in 'Mapping & Navigation' started by Truckin_Thumper, Feb 8, 2009.

  1. Truckin_Thumper

    Truckin_Thumper low profile

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    I have a pretty large track file (.gpx) that I would like to pull a series of points out and measure the time on those points.
    Only problem, I don't know how to pull them out with the info still attached. :eek1
    #1
  2. katbeanz

    katbeanz earthbound misfit, I

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    copy and paste from the track log?

    153 3/2/2008 8:36:34 AM 879 ft 147 ft 0:00:03 33 mph 92° true N36 37.536 W92 16.860
    #2
  3. tedder

    tedder irregular

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    I don't think understand what you are asking. Can't you just open it in Mapsource and analyze the track that way?

    If not, GPX is a pseudostandard based on XML; it's really easy to write code against it, if that's your thing.
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  4. Truckin_Thumper

    Truckin_Thumper low profile

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    Does each point (dot) have a unique Indentifier? If I could find that out I could follow my race tracks (Sandblast Rally) and see if my time is really what they had recorded.
    the Track I have is over 4,000 points (dots) long. :D

    I can open it in Mapsource just fine, but I cannot make out what dots go with what time.....
    #4
  5. tedder

    tedder irregular

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    They don't have a unique ID, but they do have the time attached to them- so there's a logical ordering to 'em.

    It is kind of a pain to match the specific dots up in Mapsource. There's a little trick to it- open Mapsource and your track file, then zoom in until you can see the individual dots and/or the point you want to find the correct track for. Right click on the track, click "track properties". The dot, or the leg between the dots, should be selected in the TP menu.

    Does that make sense? Try it out.
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  6. Truckin_Thumper

    Truckin_Thumper low profile

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    If'n someone would let me email the file...... :D
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  7. jwd98056

    jwd98056 Been here awhile

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    Some GPX track files have time data for each track point and some do not. It probably depends on what was used to create the file or the type/model of GPS used.

    It is very easy to associate the points with the detailed data, at least for the latest version of Mapsource. Go to the Track tab and then double click on the track name you want to analyze. This will open the Track Properties window. Click on a point in the properties window and that point will be highlighted on the map. All the data for that point is listed in the track properties window.

    Mapsource uses the time stamps in the GPX file to create "Leg Time" and "Leg Speed". There is also a total track summary at the bottom of the properties window.
    #7
  8. tedder

    tedder irregular

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    ted at perljam.net
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  9. brfinley

    brfinley Brooster

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    When you have the "track properties" window open, near the bottom on the left, click on the the checkbox "Center map on selected item(s)". Now as you navigate up and down the list with the mouse or cursor keys the map will be recentered on the selected trackpoint. It makes it easy to know the location of the selected trackpoint.

    This is also pretty handy if you are trying to edit or clean up the track file by deleting eronious trackpoints or eliminating off-trail pee breaks.
    #9
  10. tbirdsp

    tbirdsp REMF

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    Once again, you learn something new every day:D I have been SO frustrated when editing tracks, couldn't find what point I was on in the properties box, answer was right there, Thanks.
    #10