Converting GPS track to MultiLineString using GeoPandas and shapely

Question

I have many GPS tracks (long, lat, alt, timestamp) from heavy trucks. Trucks are go on some paths. How can I extract the path from GPS tracks without deviation and convert it to one MultiLineString?

I found Cushen five steps advice based on PostGIS.

I have done steps 1 (get clusters) and 2 (get centers):

But I don't know how do step 3 "generate a line that connects each cluster centre point"?

How can I connect these points to a MultiLineString using GeoPandas?

With the timestamp you could add the points in order to a multilinestring? Sort the points in an array by timestamp and then in a for loop add to a linestring as described here https://gis.stackexchange.com/questions/95670/creating-shapely-linestring-from-two-points — Timothy Dalton, Aug 21 '21 at 21:47
I have multiple tracks with gps deviation on the same roads. The problem is to remove deviation. At first step I use KMeans clusterisation and loose timestamps. — Max Sh, Aug 21 '21 at 22:10
Please do not comment on your own question. Instead [Edit] the question to contain the clarification. — Vince, Aug 21 '21 at 23:15
You can surely keep the indexes of the source points after the clustering and join the timestamps again — Timothy Dalton, Aug 22 '21 at 07:38

score 0 · Answer 1 · answered Aug 23 '21 at 06:35

First, you need to have a column for the unique truck_id and a time variable. Sort the gdf by time so the sequence of the points is correct. Then you can use groupby and agg method to make a list of points for each route.

Then use apply and LineString for converting list of points to lines:

import geopandas as gpd
from shapely.geometry import LineString
gdf = gdf.sort_values('time').reset_index(dtopr=True)
gdf_grouped = gdf.groupby(['truck_id']).agg({'geometry':list})
gdf_grouped['geometry'] = gdf_grouped['geometry'].apply(lambda x: LineString(x))
gdf_grouped = gpd.GeoDataFrame(gdf_grouped)

If you are expecting any break for a truck (two routes with same truck_id) then you need to find a way to get a unique route_id instead.

Converting GPS track to MultiLineString using GeoPandas and shapely

1 Answers1