Find curve intersection points in lat lon between rivers and satellite traces on a map

Hello, I have a set of (lon,lat) points defining the course of a river. Then I also have a set of (lon, lat) points defining the traces of satellite measurements on-ground. All are discrete finite points but of course both are in reality continuous (e.g. the river has infinite points). I want to find the intersections between both curves. It seems to be a curve intersection problem solvable with polyxpoly, but I get erratic intersections which do not make sense. Maybe because the satellite traces are not really a 'curve'? It seems so, it closes the curves of the traces which gives the erratic points

I attach a mat file with exemplary lat lon data to intersect. The provided river in fact does not intersect the satellite traces, but instead I get one invalid one. Thank you

[KSSV]

The river points falls very much with in the satelite points. They are not intersecting. How do you expect to get intersection point(s)?

[Albert Zurita]

Yes in this case there is no intersection. But using polyxpoly i get one point in the river. Can you plot the red dots instead with a line? There is why I find a fake intersection

Answer 1

[KSSV]

Try this: https://in.mathworks.com/matlabcentral/fileexchange/22441-curve-intersections

[Albert Zurita]

That is excellent! It works perfectly. I am wondering what could be the solution for the real case where instead of the satellite traces being a 1D line defined by points being an actual trace of a certain width, which would be then defined by two points (e.g. the left and the right edges of the 2D polygon). I would need to find then the intersection of the river with this '2D curve' let's call it. I can try to reformulate the problem easier.

[Albert Zurita]

I have now moved this side question to an expanded question in

https://es.mathworks.com/matlabcentral/answers/1741390-find-2d-intersection-in-lat-lon-between-curve-rivers-and-satellite-traces-2d-polygon-on-a-map