Wrong map matching using stmatch

[ziXet]

Hi,

I've been working with this library for a while and found it really elegant!

Today, I faced this issue in map matching using stmatch. I already changed the input parameters to get the correct map matching result but was not successful.

Issue:
stmatch is giving a wrong map matching result.

stmatch command:
stmatch --network ./edges.shp -k 8 -r 0.003 --vmax 0.005 --gps 1.csv --network_id id --source u --target v --output 1.out.csv --use_omp

• unit is degree

Expected behavior
stmatch should calculate the matching path correctly.

Screenshots
Input Trajectory:

Output:

mgeom:

pgeom:

Network:

Zip file including network shape file and input/output.
test.zip

Any help would be appreciated.

Thanks!

[cyang-kth]

@ziXet

The reason is that at road intersections, there are a lot of candidate edges so k=8 is too small to cover the correct candidate. After setting k=16, it seems to be correct now.

stmatch --network ./edges.shp -k 16 -r 0.003 --vmax 0.005 --gps 1.csv \
--network_id id --source u --target v --output 2.out.csv

k = 8

k = 16