[Clp] Did CLP produce an incorrect solution?

[sergey pankov]

Hi,

I am new to CLP (and to this mailing list). I have been using CLP in my
code for several days and encountered a LP program that CLP thinks it
solved successfully, but the solution is out of bounds. I am using a
ClpSimplex model (as in minimum.cpp example). Here is the solution
(columns):

                Primal          Dual         Lower         Upper
Cost
     0 c      -53.8172       0.00000       0.00000  1.79769e+308
1.32630e-06
     1 c       49.9853       0.00000       0.00000  1.79769e+308
1.01542e-06
     2 c     0.0943604       0.00000       0.00000  1.79769e+308
0.00758213
     3 c     0.0731115       0.00000       0.00000  1.79769e+308
0.0170572
     4 c       1.61406       0.00000       0.00000  1.79769e+308
0.000855447
     5 c   7.37729e-07       0.00000       0.00000  1.79769e+308
50.0000

As you can see, the first value is negative, below the lower bound. I saved
the model to a .mps file, it is attached. Am I doing something wrong? Is it
me or CLP?

Any help is highly appreciated, thank you very much in advance.

Sergey
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