Copprhead - Is there a library that helps with ...
Is there a library that helps with simplifying a track like the ones we collect with our boats, to remove times at anchor? My raw track is of several days and I would like to divide that into segments which show only the tracks of sailing.
My own idea was to simplify the track with turf.simplify, this creates gaps in the places where the positions are close to each other (-> anchoring). Then I'm parsing the track looking at the timestamps of the points and when I see too much separation, I interpret that as "new segment". It works somewhat, but the resulting track still shows some anchoring positions. Maybe there's a smarter way that takes into account how close the positions are to each other, not only the time.
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”Simplification” as in turf.simplify refers to geographic simplification. It has no notion of time. It can remove extra points from being stationary, but it won’t divide the track to segments
since it removes points (which have a timestamp), it creates chronological gaps in the track. I'm parsing the simplified track and catch on those gaps to separate the track into segments. It works quite well now with the proper tolerance - at least for my type of movement. Just thought maybe there's a more intelligent solution (ready made) that takes location and timestamp into account.
BTW, has anything changed in signalk-to-influxdb2 regarding the history query in GPX format? I'm not getting the additional attribute (like navigation.speedOverGround) anymore into the export.
http://localhost:3000/signalk/v1/history/values?paths=navigation.position,navigation.speedOverGround&from=2023-06-09T00:00:00Z&to=2023-06-12T00:00:00Z&resolution=60&format=gpx
I thought that this used to work - last year...
It's there in the JSON export but not in the GPX export.
I just use opencpn to "top and tail" before saving tracks. In track properties highlight a track point and click split, usually easy to see when the boat is moored by the speed. It's part of the end of passage check sheet.
Not that i can think of
https://github.com/tkurki/signalk-to-influxdb2/releases
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yeah looks like I didn't implement it 😉
my frontend already has the controls to select an additional path, but the gpx exporter can't do it. So either I create the gpx in my plugin from the JSON I get from the historyApi or I extend the historyApi to be able to include one extra path (probably only what's in the gpx spec) along with the positions. Have to think about it...
Since I'm doing some processing of the tracks in my plugin before I show them, from a user's perspective it might make more sense to GPX-export what they see -> create GPX in the plugin from the post-processed track data.
I don't do any manual track recording/archiving and usually don't use OpenCPN. Everything gets dumped into InfluxDB and later I pull out what I'm interested in.
another option to try could be load vscode with the gemini code completion extension then spend 10 mintes describing exactly what you would like to do and get it to write some python. Only played around a bit so far but it seems to often nail it straight away or if not paste any error messages in & it will fix them. Might have a play later, cut into 2 where speed is below xx & positions are within xxx within 20 minutes of xxx. It will write a window with menus to load & look at GPX. We are all coders now, just need to create the right prompts 😎 This is one Ai written to look at waypoint symbols https://i.imgur.com/xqg0a2u.png