[Coin-discuss] OsiOsl bug ?

[John J Forrest]

Tim,

It is a "feature" - there may be a bug but not where you think.

When Osl finds a solution it sets a "bound" of solution - epsilon (default 
1.0e-5).  OsiOsl picks up this and stores it so in this case it is as if 

Solver->setDblParam(OsiDualObjectiveLimit,-1.0e-5);

After second branch and bound the test for provenOptimal etc tests 
objective value of 0.0 against -1.0e-5 and says not optimal which is 
correct.

To get the behavior you want add this before second solve.

Solver->setDblParam(OsiDualObjectiveLimit,1.0e50);

The bug?  Osl seems to say that it found an optimal solution when it 
should not have.  I will look into it to see if OsiDualObjectiveLimit is 
not being passed in to Osl correctly.

John Forrest
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