Re: [Help-glpk] different result

[Andrew Makhorin]

> i already solve a problem with glpk, but i want to validate it with
> calculate the objective function in excel
> but i have the different value between objective function in glpk and
> excel.
> glpk's objective function was 1805582104 , but if i calculate it with
> excel it was 1838084829
> hereby i attached my problem, thanks in advance
>  

I converted your instance to mps format and posted it to the neos server
to solve with gurobi:
http://www.neos-server.org/neos/solvers/milp:Gurobi/MPS.html

---------- Begin Solver Output -----------
Executing /opt/neos/Drivers/gurobi/gurobi-mps-wrapper-driver.py at time: 
2012-09-02 15:58:10.870839
Load Avg: ( 1.0 , 1.0 , 1.0 )
Read MPS format model from file model.mps
Reading time = 0.01 seconds
sensitiv: 680 rows, 1140 columns, 3586 nonzeros
Changed value of parameter Threads to 4
   Prev: 0   Min: -1   Max: 12   Default: 0
Optimize a model with 680 rows, 1140 columns and 3586 nonzeros
Presolve removed 467 rows and 861 columns
Presolve time: 0.03s
Presolved: 213 rows, 279 columns, 841 nonzeros
Variable types: 0 continuous, 279 integer (0 binary)

Root relaxation: objective -1.805582e+09, 234 iterations, 0.00 seconds

    Nodes    |    Current Node    |     Objective Bounds      |     Work
 Expl Unexpl |  Obj  Depth IntInf | Incumbent    BestBd   Gap | It/Node Time

     0     0 -1.806e+09    0   13          - -1.806e+09     -      -    0s
H    0     0                    -1.80536e+09 -1.806e+09  0.01%     -    0s
H    0     0                    -1.80558e+09 -1.806e+09   0.0%     -    0s

Cutting planes:
  Mod-K: 1

Explored 0 nodes (257 simplex iterations) in 0.06 seconds
Thread count was 4 (of 12 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective -1.805582103655e+09, best bound -1.805582103655e+09, gap 0.0%
Optimal objective: -1805582103.66