Shortest route model - looping on itself?

GAMS
1

I have moddeled a case that defines the shortest route between 2 cities, but for my exercise there has to be the posibility that you can go from/to any of the cities.

In this case i have a main hub, “ATLANTA”, and i need to arrive to “ISTANBUL”; the problem is, when solved, the model goes from the shortest point to both Atlanta and Istanbul - and back to them, but doesn’t have a feasable route from one to another.

Here is an extract of the “Ideal route” its giving me at the moment:

 		ATLANTA  WASHINGTON    ISTANBUL       CAIRO

ATLANTA                         1.000
WASHINGTON          1.000
ISTANBUL                                                1.000
CAIRO                                       1.000

The code is left attached w/ the post.

Any help would be very appreciated!

2

Look at the topic https://newforum.gams.com/t/shortest-path/2312/1

  • Michael