Does the driving direction have an impact on distances?

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Bernd Welter
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Does the driving direction have an impact on distances?

Post by Bernd Welter »

Hi there,

every once in a while customers wonder about the difference of distances depending on the relations direction.
In other words:
  • Why is the distance(A:B) not always equal to distance(B:A)?
  • Why is a distance matrix not symmetric?
The core answer to these questions is simple but requires more details:
The geometry of the routes is not the same, e.g. other roads are used.
Route from Stuttgart to Madrid and back.<br />In the region of Lyon the router takes different superregional tracks
Route from Stuttgart to Madrid and back.
In the region of Lyon the router takes different superregional tracks
Of course the next question is then "why does the router not use the same streets?"

And then it comes to speed values and optimization. Here's another example:
DIRDistancePeriodCOSTTrack
N to S2060707194101666WEST
N to S +1862097733102025EAST
S to N1842617786102031EAST
S to N +2046477370102765WEST
So sometimes adding waypoints creates better distances and worsens the period. If the route is focused on period the +ROUTE is not better then.

Best regards,
Bernd
Attachments
South to North plus waypoint
South to North plus waypoint
South to North
South to North
North to South plus additional waypoint
North to South plus additional waypoint
North to South without any additional waypoints
North to South without any additional waypoints
Bernd Welter
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PTV Logistics - Germany

Bernd at... The Forum,LinkedIn, Youtube, StackOverflow
I like the smell of PTV Developer in the morning... :twisted:
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Bernd Welter
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Posts: 2564
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Re: Does the driving direction have an impact on distances?

Post by Bernd Welter »

"Frankfurt Abflugbogen" (Frankfurt Airport: Departure) to "Frankfurt Ankunftbogen" (Frankfurt Airpoirt, Arrivals)

Absolute difference is not that big but from a relative perspective it is enormous:
1.200m versus 86m ;-)
Attachments
AB-notEqual-BA.PNG
Bernd Welter
Technical Partner Manager Developer Components
PTV Logistics - Germany

Bernd at... The Forum,LinkedIn, Youtube, StackOverflow
I like the smell of PTV Developer in the morning... :twisted:
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