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Does Locus use <speed> tag?

ulmus shared this question 9 years ago
Answered

Doeas Locus Pro use speed tag? I dont think so :(

If Locus calculate speed using 2 points then what if i edit gps and delete wrong points(e.g. wrong position because of inside building) then speed might be very very high! In my case it was 222km/h when in tags i have a little over 30km/h!

What if my receiver for (every track point) gives a speed in tags?


I have gpx with such example data, can Locus handle that:


<trkpt lat="00.000000000" lon="00.000000000">

<ele>93.300781</ele>

<time>2014-06-16T14:01:20Z</time>

<speed>0.240000</speed>

<extensions>

<speed>0.2</speed>

<temp>0.00</temp>

<bpm>0</bpm>

<rpm>0.00</rpm>

</extensions>

</trkpt>

Replies (9)

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1

Hi Ulmus,


Locus parse and read 'speed' value from a file. Anyway in case, not all points in your track has defined speed value, then Locus automatically recompute this value by distance and time between points. So it should be your case.


If you share any track with these troubles, I'll check it.

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Please look into:

http://help.locusmap.eu/responses/sometimes-rate-in-track-has-very-high-value#comment-12405


I have points with such data too:


<trkpt lat="00.7332916" lon="00.4910984">

<ele>132.4</ele>

<time>2014-07-05T08:34:00.000Z</time>

<name>Position 3</name>

<extensions>

<nmea:speed>2.9</nmea:speed>

</extensions>

</trkpt>

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I'm checking 2014-07-05.zip you mentioned and I still see no problem.


There is for example on line 37756


  1. <gpxtpx:speed>60.66949</gpxtpx:speed>

which is 218 km/h! So values you see in Locus are correct right because Locus takes speed from tag!


You second possibility with 'nmea:speed' won't work, because Locus do not know such tag 'nmea:'

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60.66949 == 218?

maybe units are different but this (the file i gave link) is exported from locus, but when i imported data into locus, gps file has speed value in tags like this:

<speed>60.66949</speed>

without any unit.

and i am sure it is in km/h not miles or something.

I dont know anything about gpx format, and dont know if it is in mph or km/h

or something else, but i know that gpx files exported from my holux receiver has speed value in km/h

so... gpx speed tag has its own unit of speed where 1unit=218/60.66=3.6 km/h?

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OK, for now EOT!

I will try to download raw data from receiver and import into locus once more, taking as much control over it as i can to be sure what i am writing about.

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hmm then you Holux has serious problem, because speed in GPX are always in metres per second, more for example here http://gis.stackexchange.com/questions/74222/what-are-the-units-for-garmins-gpx-gpxtpxspeed


then 60 m/s ~ 220 km/h

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hmmm, maybe i am wrong saying that i am sure about km/h...

as i said, i will download raw data from holux and will see...

now i am not sure if i was downloading data from locus using android MTK application,

so... i will write later when i will be sure 100% what i am writing...

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1

Ok, now i know something more:

speed that is about 100 and 200 km/h, it is altitude! :):):)

I dont know what application made this error but now i know what it is :)

So... topic is to be closed.

I think that MTK application made that error and download altitude as speed...

I deleted MTK and will use pc app to download holux data and then into locus...

Thanks for helping me clear the problem!

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oki fine, this make a sense :). You're welcome

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