Matrix routing with destinations close to motorways - here-api

Question

I have a number of locations between which I want to know the travel time and distance.
The locations have been correctly geocoded. However, the problem I am experiencing is that some of the locations lie between a regular road and a motorway. In fact, they lie closest to the motorway.
In this case, the travel time and distance I receive consider the location to lie on the motorway (the closest road), which leads to an incorrect estimation of the actual travel time and distance.
Given that I cannot manually adapt each geocode to lie closest to the regular road, I need a different solution.
I included 'street!!' in my call as indicated on https://developer.here.com/api-explorer/rest/routing/route-to-location-near-motorway but to no avail.
My call looks like this "https://matrix.route.api.here.com/routing/7.2/calculatematrix.json?start0=x.x,y.y&destination0=street!!x1.x1,y1.y1&mode=fastest;car;traffic:disabled&summaryattributes=traveltime,distance&app_id=...&app_code=...".
Is there another way to avoid that Here puts the destination on the motorway?
Your help would be greatly appreciated. Thank you in advance!
Below you find one example
Geocodes of departure: 51.090995,4.018793
Geocodes of destination: 51.017960,3.694040 (close to E40/A10 in Belgium)
When I use the matrix routing API, I get a distance of 29799 meters and a travel time of 1317 seconds.
My call:
"https://matrix.route.api.here.com/routing/7.2/calculatematrix.json?start0=51.090995,4.018793&destination0=street!!51.017960,3.694040&mode=fastest;car;traffic:disabled&summaryattributes=traveltime,distance&app_id=...&app_code=..."
When I use the routing API to get the directions, I can see that my destination is updated to 51.0187054,3.6935735, which is on the E40/A10. This gives me a distance of 29827 meters and a travel time of 1335 seconds.
I used the call below:
"https://route.api.here.com/routing/7.2/calculateroute.json?app_id=...&app_code=...&waypoint0=51.090995,4.018793&waypoint1=street!!51.017960,3.694040&mode=fastest;car;traffic:disabled"
Given that the distance and travel time differs, I executed my matrix routing API call again with the updated destination geocodes (51.0187054,3.6935735). This provided me with the same distance and travel time as my initial matrix routing request, i.e. 29799 meters and 1317 seconds.
I used this call:
"https://matrix.route.api.here.com/routing/7.2/calculatematrix.json?start0=51.090995,4.018793&destination0=street!!51.0187054,3.6935735&mode=fastest;car;traffic:disabled&summaryattributes=traveltime,distance&app_id=...&app_code=..."
As such, I am sure the destination is on the E40/A10. How can I avoid this?
On a related note, why do the travel time and distance differ between the matrix routing API and the routing API?
When I enter the geocodes in GoogleMaps, I actually get the position I wanted.
As you can see, it is not on the E40. Why can't I get a route to the nearest regular street?

Answer 1

So taking the example you gave, the destination waypoint 51.017960,3.694040 lies very close if not on the E40/A10 itself. See image below:
Moreover, using our reverse geocoder API to get the list of address within 200m radius of the destination waypoint returns only addresses (points) along the E40, 9052 Gent, België with street match level . There is therefore no way for the algorithm to know which nearby street you intend to arrive when the waypoint is many hundreds of metres off. I will suggest to correct your waypoints using our reverse geocoder api to determine which waypoints are way off your intended address.