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I have digitised a track in QGIS from Maps.me screen shots but when displayed it is confusing as it crosses and backtracks several times.

I would like to display the track in short segments in Temporal as an animation but have had no success.

I tried recording the track in short segments as a line string with a date time field but there was no opportunity to add a time when each segment was saved so consequently no time for Temporal to work on.

If it is not possible to digitise with time I wondered if it would be possible to extract the coordinates from my original file and add them to a csv with a date field? However I can't find a way of extracting the coordinates.

I am competent with tracks, points and loading via csv but have very limited knowledge of Python.

I have formatted data as shown by Kasper but when I try to Add Layer- txt file it shows 2 symbols before the wkt and there is no track on map and an error triangle in Layers saying Unavailable layer! Loading data

Screen shot of data in Notepad. Data in Notepad

Extra characters were caused by incorrect date, now corrected. Still have error I don't understand. Error in Layers Dialog displayed when Error clicked

link to data file Data as loaded

Sorry missed your comment Kasper, no PW added but try this link Same file different location

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  • I went to Create Layer, New Spatialite Layer, specified name/location, Geometry type-Linestring, New Field-Date,Add to fields list. However it never asked me to add date when creating the geometry. I have since exported original the track as a kml and extracted coordinates in Notepad++. I then used Libra Write & Calc to format and add date, saved as csv. This works as an animation but gives me a series of points rather than lines, not as elegant as I'd hoped
    – Vic
    Commented Jan 8, 2023 at 17:37
  • I was hoping to have small segments that appear along the animation.
    – Vic
    Commented Jan 8, 2023 at 17:45
  • Pardon my ignorance but I've not come across WKT Linestring before and have no idea how to edit such a beast.
    – Vic
    Commented Jan 8, 2023 at 17:55
  • I'll try that tomorrow, thank you.
    – Vic
    Commented Jan 8, 2023 at 21:13
  • Are you fine with interpolated DateTimes for the segments? For this you would just need lines, startdatetimes and enddatetimes.
    – MrXsquared
    Commented Jan 9, 2023 at 18:17

1 Answer 1

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You can format your .csv like the following:

wkt;date
LINESTRING(0 0,0 1);2022-01-01 13:00:00
LINESTRING(0 1,0 2);2022-01-01 14:00:00
LINESTRING(0 2,0 3);2022-01-01 15:00:00
LINESTRING(0 3,0 4);2022-01-01 16:00:00
LINESTRING(0 4,0 5);2022-01-01 17:00:00
LINESTRING(0 5,0 6);2022-01-01 18:00:00
LINESTRING(0 6,0 7);2022-01-01 19:00:00

Then import as delimited text file, geometry should be WKT, data field as Date & Time

If you load it as such, it will display all the small Lines as a continous line: enter image description here

If you animate that layer based on the date field, you get each item displayed one by one (depending on the animation settings and the time granularity in the source data):

enter image description here

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    Clear now, just need to get data into required format.
    – Vic
    Commented Jan 9, 2023 at 14:38
  • Added link to data file at end of question.
    – Vic
    Commented Jan 12, 2023 at 18:43
  • Dded Dropbox link.
    – Vic
    Commented Jan 13, 2023 at 10:23

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