[Cbc] CBC doesn't reach the optimal solution

[John Forrest]

Juliette,

Thanks for reporting the bug.  I tracked it down to knapsack cuts and it 
was still in Cbc stable/2.9 - just didn't occur.

Rare circumstances - but very definitely a bug.

Fixed in Cgl/stable/0.59 and trunk (so in Cbc stable/2.9,2.10 and trunk)

John Forrest
On 29/01/15 10:53, Juliette Medina wrote:
> Hi,
>
> I would like to report a bug on the optimal found by CBC.
> When testing my model on various solvers, I discovered that CBC 
> doesn't reach the optimal solution.
>
> CBC finds 1664.1149999999998  whereas the optimal solution is 
> 1552.7400000000002 (with Cplex).
>
> Do you mind giving me a feedback about why it doesn't work properly?
>
> Here the LP model below :
>
> Thanks