Re: [Help-glpk] Obtaining the optimal tour from tspsol

[Andrew Makhorin]

> Is it possible to obtain the optimal tour when running tspsol, i.e., the
> order of nodes to visit?

You may use the following command:

tspsol infile -o outfile

in which case the solver writes the solution to 'outfile' in a plain text
format (like glpsol).

For example:

   No. Column name  St   Activity     Lower bound   Upper bound    Marginal
------ ------------ -- ------------- ------------- ------------- -------------
     1 1-2*         NU             1             0             1          -280
     2 2-3*         NL             0             0             1            20
     3 3-6*         NU             1             0             1           -10
     4 6-8*         NL             0             0             1           160
     5 4-8*         B              1             0             1 
     6 4-5*         NU             1             0             1           -50
     7 5-7*         NU             1             0             1          -290
     8 1-7*         NL             0             0             1           260
     9 1-5          NL             0             0             1           110
    10 2-6          B              0             0             1 
    11 1-3          B              0             0             1 
    12 7-8          B              0             0             1 
    13 5-8          B              0             0             1 
    14 1-6          B              1             0             1 
    15 2-7          B              0             0             1 
    16 2-8          B              1             0             1 
    17 3-7          B              1             0             1 

If some variable, say, '3-7', is 1 (see 'Activity'), the corresponding
edge is included in the optimal tour, otherwise not.