Geographic TSP instances based on United States Cities

The files of the form city<n>.ll hold the longitude and latitude of the largest n cities in the United States (excluding Alaska and Hawaii) in millionths of a degree. (Longitude is degrees west of Meridian; latitude is degrees north of the equator.)

The files of the form city<n>.lab hold the gazateer data for the cities in the same order as city<n>.ll so you can label the cities with their names. This is not needed to contruct the problem instance.

If lon[c] and lat[c] are the longitude and latitude entries of file city<n>.ll for city c, then the distance between two cities x and y in tenths of a kilometer would be:

or you can use the following code to convert a file named city.ll to a full n by n matrix in a file named city.mtx.

Here are the problems:
For the asymmetric TSP problem generator developed by Bruno Repetto, click here.
Neil Simonetti