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[done] Speed problem

Posted: Sun Jul 29, 2012 7:55 pm
by inode
Hi,

I'm incurring in some problems with the stats of alpinequest. The max speed and the graphs are wrong... I know the data could be wrong and the stats are based on the data, but it's possible to "normalize" data and automatic remove anomalies?

Here you can find an example:

http://inode.photofor.us/track_20120721 ... natti_.gpx

If you import the data on alpinequest you can see there is some problem with speeds in a lot of points...

Requestes:

- it's possible to have a feature that "normalize" the data removing anomaly?
- it's possible to have informations about the "point" of the track during the graph visualization?

Thank you.

inode

Re: Speed problem

Posted: Wed Aug 01, 2012 3:46 pm
by Psyberia-Support
Hi and thanks for your feedback.
I have displayed your track and see what you mean.

Before computing statistics, a filter and a smoothing is already applied on the data to remove GPS inaccuracies (in the details, you can compare the number of points between the raw data and the filtered data), but it won't remove what you got, because it's really difficult to detect if it's a normal behavior or not. If you are using a car, you may move very fast and then very slow just after.

A good feature would be something like you suggest in point 2, or maybe even better, be able to manually remove points from the graph view.
This is a common issue so I will try to add this feature soon.

Concerning the point 1, I will think about what could be done, but as I told you it's quite difficult to automatically detect these imperfections.

What I usually do to avoid that at the beginning, is to wait for a good GPS accuracy before starting the GPS tracker.

Note also that your track is made of 3 segments, the first one seems to be the worse.

Best regards

Re: Speed problem

Posted: Wed Aug 01, 2012 3:49 pm
by Psyberia-Support
I have added this feature in the wanted features list.

Re: Speed problem

Posted: Fri Aug 03, 2012 7:47 am
by inode
Thank you!

Re: Speed problem

Posted: Fri Aug 31, 2012 9:59 pm
by Psyberia-Support
Hi,
I have released AlpineQuest 1.3.4 containing this feature.
Here is how to proceed:
- display the track on the map;
- click on it;
- select "Remove points";
- select points using the profile or the 'Previous' and 'Next' buttons;
- remove points using the 'Delete' button.
- close the sideview and select save the file.

The profile and on map display is updated after each delete.
Best regards